Emmanuel Ademola Anigilaje
Zaheer Ahmad Nasir
Christopher Walton*‡- School of Water, Energy and Environment, Cranfield University, Cranfield, United Kingdom
Introduction: In Nigeria, because of increasing population, urbanization, industrialization, and auto-mobilization, petrol is the most everyday non-edible commodity, and it is the leading petroleum product traded at the proliferating Nigeria's petrol stations (NPSs). However, because of inadequate occupational health and safety (OHS) regulatory measures, working at NPSs exposes petrol station workers (PSWs) to a large amount of hazardous benzene, toluene, ethylbenzene, and xylene (BTEX) compounds.
Methods: Studies on BTEX exposures among Nigerian PSWs are scarce. Thus, constraints in quantifying the health risks of BTEX limit stakeholders' ability to design practical risk assessment and risk control strategies. This paper reviews studies on the OHS of Nigerian PSWs at the NPSs.
Results: Although knowledge, attitude, and practices on OHS in NPSs vary from one Nigeria's study setting to another, generally, safety practices, awareness about hazards and personal protective equipment (PPE), and the use of PPE among PSWs fell below expectations. Additionally, air quality at NPSs was poor, with a high content of BTEX and levels of carbon monoxide, hydrogen sulfide, particulate matter, and formaldehyde higher than the World Health Organization guideline limits.
Discussion: Currently, regulatory bodies' effectiveness and accountability in safeguarding OHS at NPSs leave much to be desired. Understanding the OHS of NPSs would inform future initiatives, policies, and regulations that would promote the health and safety of workers at NPSs. However, further studies need to be conducted to describe the vulnerability of PSWs and other Nigerians who are occupationally exposed to BTEX pollution. More importantly, controlling air pollution from hazardous air pollutants like BTEX is an essential component of OHS and integral to attaining the Sustainable Development Goals (SDG) 3, 7, and 11.
1 Background and purpose
The petroleum products traded at Nigeria's petrol stations (NPSs) are engine lubrication oil, petrol, diesel, kerosene and cooking gas, but petrol is the leading commodity (1). In 2018, there were 29,197 petrol stations in Nigeria (2). This proliferation is attributed to the country's increasing population, urbanization, industrialization, auto-mobilization, and energy use (3, 4). The daily petrol consumption in Nigeria is about 93 million liters (5). With 198 million people and a motor vehicle population of 11,760,871 in 2018, Nigeria has 0.06 vehicles per person (6). However, most (97.4%) of the available vehicles in Nigeria are imported second-hand vehicles (7), which have been associated with low energy efficiency, high fuel consumption, and high emission of greenhouse gases (GHGs), including carbon dioxide, carbon monoxide, nitrogen oxides, unburned hydrocarbons, and particulates such as soot and ash (8–11). Furthermore, within Nigeria's context of perennial inability to generate, transmit and distribute sufficient electricity (12, 13) and the unaffordability of zero-emission electric vehicles (ZEEVs) (14), Nigerians will continue to depend on gasoline and diesel for their auto-mobiles, and for fuelling their electric generators at homes and businesses (4, 15–17). In Nigeria, petrol station workers (PSWs) typically dispense fuel, unlike self-service dispensers, which are more common in advanced countries (4). Thus, NPSs are an indispensable sector of Nigeria's economic activities, where humans and petroleum products will continue to interact. Unfortunately, the petrol being officially sold in Nigeria has a permissible content of benzene of 2% v/v1 compared to 1% (v/v) in Europe (18) and 0.62% (v/v) in the United States (19). In general, petrol contains about 2–18% of benzene, toluene, ethylbenzene and xylene (BTEX) (20, 21). BTEX harm the environment and human health because of their properties and residence times in the atmosphere (22). Nevertheless, BTEX must be added to unleaded gasoline and diesel to act as an antiknock and lubricating agent to improve machine efficiency (23, 24).
BTEX is a mono-aromatic mixture found in natural and anthropogenic sources (25). The natural sources of BTEX are natural gas and petroleum deposits, volcanoes, and wildfires (25). The anthropogenic sources include emissions from aircraft and cigarette smoke; however, in urban areas, the combustion of gasoline and diesel fuels, especially for motor vehicles, constitutes an essential source of BTEX (25–27). Additional sources of BTEX in urban air are emissions from gas stations and small-scale industries that use chemical compounds containing BTEX (paint, adhesives, etc.) (28, 29). BTEX is also a common additive to some chemical intermediates, pharmaceutical products, and consumer products (inks, cosmetics) (30).
BTEX is the main representative of volatile organic compounds (VOCs) (31). By definition, VOCs are photochemically reactive species with high vapor pressure in the Earth's atmosphere (32).VOCs are hazardous air pollutants (HAPs) because they are harmful to the environment and human health due to their properties and residence times in the atmosphere, which can last from a few minutes to several months (22, 23, 33). The residence time of BTEX in the atmospheric air depends on air dispersion and photochemical decomposition with hydroxyl (.OH) oxidant and chloride radicals (34). Thus, apart from diffusion and distance from the source (31, 35), BTEX concentration in the atmospheric air also depends on the BTEX content of the fuel (36) and on atmospheric hydroxylation, which is dependent on temperature (37), seasonal, geographical, altitudinal and diurnal variations (38). According to Atkinson et al. (39), benzene has an estimated lifetime reaction with OH radical of 9.4 days, followed by toluene (1.9 days), ethylbenzene (1.6 days), o-xylene (0.8 days) and m, p-xylene (0.6 days). In other words, while xylene is considered a highly reactive species, ethylbenzene and toluene are less reactive, and benzene is a relatively stable species (40). The concentration of BTEX is usually lower in warmer months due to the strong photolysis and the dilution caused by the increase in the depth of the mixing layer (41). Furthermore, the concentration of BTEX tends to increase during winter due to the frequent occurrence of the inverse temperature layer (31). BTEX accumulation in the air is also higher during cloudy days than sunny days due to lower temperatures and light intensity (31). The BTEX contents are also affected by factors such as prevailing wind direction and wind velocity (42).
Although exposure to BTEX is usually a simultaneous exposure to all its constituent parts, the harmful impacts on human health are better appreciated by considering the individual impacts of each constituent, as multiple human epidemiological studies are available (25). Table 1 summarizes the acute and chronic effects of BTEX in humans (43–46). TEX also forms secondary air pollutants, including ozone, ultra-fine particulate matter, and polycyclic aromatic hydrocarbons that contribute to ill health in humans (31, 47–50).
Table 1. The acute and chronic effects of BTEX in humans.
Human occupational exposure to BTEX from petrol is a significant health concern, and pieces of evidence abound to prove that PSWs are more at risk of BTEX exposure and health hazards (21, 51, 52). Quantifying BTEX exposures and the health risks among PSWs have been of research interest in Asia, Europe, Canada, and North America (18, 52–64). The results of these studies indicated that PSWs were at a higher risk of adverse cancer and non-cancer health risks (52, 56, 60, 62, 64–66). Although the petroleum oil and gas industry contributes about 9% to Nigeria's gross domestic product (GDP) (67), assessing BTEX exposure among PSWs is a rare research focus in Nigeria. This dearth of data exists despite prevailing conditions that expose PSWs in Nigeria to a high volume of BTEX. For example, the dispensing pumps at Nigeria's filling stations are often powered by gasoline-electric generators, which add to the ambient air pollution at the filling stations. In addition, most of these dispensing pumps have no mechanism for vapor recovery (68, 69), and some of Nigeria's PSWs work for long hours daily ranging from 10 h (69) to more than 12 h (70). Exposure to petrol/BTEX is expected through the skin via inadvertent spills on the body while dispensing petroleum products as the use of personal protective equipment (PPE) is uncommon (16, 71–73). Exposure to BTEX through the gastrointestinal tract also happens due to poor personal hygiene as PSWs on working shift take their meals without washing their hands (16, 69), and PSWs occasionally siphon fuels from the tanks of automobiles (70, 74).
Furthermore, although the four Nigerian crude oil refineries (Port Harcourt I and II, Warri, and Kaduna) run by the state-owned Nigerian National Petroleum Corporation (NNPC) can process 445,000 barrels of crude oil daily, they operate for < 50% of their capacity for years before they were shut down in 2020, having reached zero refining activity in 2019 (75). As of 2017, the total demand for petroleum products in Nigeria was 750,000 barrels per day, already more than the refineries' 445,000 barrels capacity (76). Consequently, 70–80% of the country's petroleum products are imported to meet the national demands (76). Reasons for the underutilization of the national refineries include poor governance, lack of major turnaround maintenance, vandalization of pipelines supplying crude oil to refineries and pipelines carrying petroleum products from the refineries, and inappropriate regulations of the price of the petroleum products that lead to under-recovery of crude oil cost (76). West Africa imports around 50% of its fuels from Amsterdam, Rotterdam, and Antwerp (“ARA” region) (77). However, 80% of the diesel exported from ARA to Africa has sulfur content at least 100 times above the European standard (77). Africa's weak fuel standards enable European traders to use low-quality, cheap blend-stocks to produce low-quality “African Quality” fuel, which damages health with high sulfur, aromatics, and benzene levels (77, 78). Thus, while countries in West Africa export crude oil with low sulfur content, they import petroleum products with high sulfur content from Europe and the US (77). Since the report of Gueinat et al. (77), five West African countries (Nigeria, Ghana, Benin, Togo, and Cote d'Ivoire) announced that they will ban the import of high-sulfur fuel (79). However, Nigeria's current specification for sulfur content in petrol remains at 150 part per million (ppm)2, value that is still higher than the European limit of 10 ppm (77).
Nigeria's leading petrol and diesel imports are from the Netherlands, Belgium, India, Norway, and the United Kingdom (80). However, imported petrol from Antwerp in February 2022 was found to have an excess amount of methanol, causing engine damage in vehicles in Nigeria (80). This highlights poor quality checks for petrol specification at load ports and in Nigeria and the need for stringent regulations to ensure the safety and quality of imported products. Furthermore, before 2004, Nigeria was one of the countries with high Tetraethyl lead (TEL) concentration as an octane promoter in its gasoline. However, Nigeria adopted the “Phasing-out leaded gasoline in Nigeria's Initiative” of the World Bank Clean Air Initiative. Nigeria adopted a two-step approach, reducing to 0.15 g Pb/l from 0.2 g Pb/l by the end of 2002 and a total phase-out of leaded gasoline by 2004 (81, 82). Although Nigeria was officially acknowledged to have phased out leaded gasoline in 2004, some Nigerian investigators (83–89) have documented higher blood levels of lead among Nigerian PSWs compared to controls that were not occupationally exposed to gasoline. These findings may not be unexpected as gasoline in Nigeria still contains a lead specification of 50 ppm (see text footnote 2).
To inform future initiatives, policies, and regulations that will safeguard Nigeria's PSWs, a better understanding of the occupational health and safety (OHS) of NPSs is required. Specifically, the burden and the challenges of exposure to BTEX at NPSs must be well-documented. Unfortunately, the inability to quantify the health risks (cancer and non-cancer risks) of BTEX will continue to limit Nigerian stakeholders in designing practical risk assessment and risk control strategies. The detection and quantification of air pollution at Nigeria's petrol stations will significantly enhance workplace health and safety standards by pro-actively addressing occupational risk factors that may affect the wellbeing of employees. It will enable swift and resolute measures at every level, including petrol stations, regulatory bodies, and policy-makers, to avert work-related illnesses and injuries and foster optimal workers' health. Studies on OHS at NPSs are essential for stakeholders to establish a baseline, track progress, draw comparisons, and advocate for risk control strategies.
While prefacing a background of Nigeria's geography and energy mix and Nigeria's environmental pollution and climate actions, this paper reviews the existing studies on air quality at NPSs, including observational and analytical studies on OHS of Nigerian PSWs at the NPSs. The review describes the exposure of Nigerian PSWs to BTEX/petrol and other hazards at NPSs. It presents opportunities for a future direction to safeguard the health and safety of Nigeria's PSWs and others who may be occupationally exposed to petroleum products.
1.1 Nigeria's geography and population
Nigeria has an area of 923,768 square kilometers and is the most populous country in Africa, with an estimated population of about 225 million people in 20223. Nigeria comprises 36 States and Abuja, the Federal Capital Territory (see text footnote 3). The States are aggregated into six geopolitical zones: North-west (NW), North-east (NE), North-central (NC), South-west (SW), South-east (SE), and South-south (SS) (Figure 1). The countries at Nigeria's borders include the Benin Republic to the West, Cameroon to the East, and the Niger Republic to the North (see text footnote 3). Nigeria is a lower middle-income country (LMIC) (90). As of 2022, Nigeria's GDP is 477 United States Dollars (USD), Gross National Income per capita is 2,140 USD, and the total unemployment rate is 5.8% (90). Nigeria is a major producer and exporter of oil in Africa, with significant crude oil reserves, which stood at 37,448.25 million barrels in 2014 (91). Nigeria's crude oil accounts for about 9% of the total GDP and 96% of its export earnings (67, 92, 93).
Figure 1. Map of Nigeria showing the 36 states and federal capital territory as well as the six geopolitical zones. Reproduced from Management Commission. niMC enrolment centers. Available from: https://www.nimc.gov.ng/nimc-enrolment-centres/.32. Available via license: Creative Commons Attribution-NonCommercial 4.0 International.
1.2 Nigeria's energy and electricity mix
Nigeria's primary energy consumption in 2017 was about 1.5 quadrillion British thermal units (94). Natural gas (42%), petroleum, and other liquids (55%) are the major energy consumption, while traditional biomass and waste (wood, charcoal, manure, and crop residues), coal, and renewable energy only accounted for 3% (94). Some Nigerian households use biomass energy to cook in poorly ventilated kitchens (95, 96).
In 2017, Nigeria's generation capacity was 12,664 megawatts (MW), of which 10,522 MW (83%) was from fossil fuels, 2,110 MW (17%) was from hydroelectricity, and 32 MW (< 1%) was from solar, wind, and biomass and waste (94). The solar energy is available to very few Nigerians (97). Net electricity generation was far lower than capacity and was 30.6 billion kilowatt-hours (3,495 MW) in 2017, or about 28% of total capacity (94). Although Nigeria is the continent's largest economy, only 60% of the population had access to electricity in 2018 (94). Most of Nigeria's fossil fuel-derived electricity is from natural gas, and crude oil is mainly used for backup power generation (94). Nigeria does not generate energy from nuclear or geothermal sources (91).
Although Nigeria has ambitious electricity mix targets, generating electricity faces persistent challenges, including inadequate power generation due to financial constraints, and problems with energy transmission and distribution (12, 93, 98, 99). Privatization of generation and distribution has yet to eliminate these problems (12, 98). Transmission challenges include mismanagement issues, poor maintenance, and inefficient grid design (12, 98). Consequently, Nigeria's electricity shortfall is met with diesel and gasoline-powered electric generators at homes and at business centres, with some of these electric generators operating between 15 and 18 h a day (17). A staggering $22 bn (about 5% of GDP) is spent yearly to fuel electric generators in Nigeria (93).
1.3 Nigeria's environmental pollution
Because of increasing population and rapid urbanization, Nigeria is replete with many environmental problems, including rapid deforestation, soil degradation and loss of arable land, illegal exploration and refining of crude oil, uncontrolled gas flaring, and ambient and household air pollution [(100); see text footnote 3]. Gas-flaring in Nigeria is seventh in the world (6.6 billion cubic meters of flared gas) producing about 17.76 Mt of CO2 emissions as of 2021 (101). Electric generators are sources of air pollution emitting fine particulate matter (PM) and black carbon from internal combustion of diesel and gasoline. Nigerians also buy fuel in plastic containers for their electric generators from the filling stations (102); air pollution also results from evaporative and spillage losses of diesel and petrol in transit from these plastic containers. Nigeria's efforts at mitigating air pollution from electric generators culminate in the flagging off of the National Generator Emission Control Programme (NGECP) in January 2023 (103). The NGECP involves yearly testing of electric generators for toxic and GHG emissions (103). Other sources of ambient air pollution in Nigeria include the burning of e-waste, emissions from waste incinerators, gaseous emissions from dump sites, and gaseous emissions from industries (104, 105). Thus, many Nigerians suffer pollution-related health problems (106) including cardiovascular diseases, mental health problems, and chronic obstructive pulmonary diseases (pneumonia, emphysema, and bronchitis) (107). Nigeria is the fourth leading country with deaths from air pollution (108). An estimated 114,000 Nigerians die from air pollution each year in Nigeria (108). Air pollution was also reported to be a major risk factor responsible for 15% of under-five mortality in Nigeria (109).
1.4 Nigeria's transportation system and transportation-related pollution
The commonest source of BTEX in urban areas is transportation activity resulting from incomplete combustion in motor vehicles (110, 111). The transport sector is Nigeria's greatest carbon-dioxide emitter, accounting for about 60% of total national emissions (94). It comprises road, rail, air, and marine sub-sectors; however, the road transport sector is the primary means of moving goods and people across the country (92, 112). Road transport contributes significantly to the nation's GDP (2.7%) (92). Nigeria's transport system comprises more of the least energy-efficient (road and air transport) system, which emits higher GHGs compared to the most energy-efficient sub-sectors (rail and water transport) (14). Passenger transport dominates road transport, as evidenced by a predominance of privately owned cars and light commercial vehicles (92). In 2018, ownership of road vehicles in Nigeria comprised commercial (57.70%), private (40.98%), and Government and diplomatic (1.32%) vehicles (6, 14). Nevertheless, Nigeria's opportunities for low-carbon transport include the use of biofuels (1.5 billion liters planned capacity), natural gas (187 trillion cubic feet) with the use of Compressed Natural Gas (CNG) fuelled vehicles, electrified transport coal (2.7 billion tons), or natural gas power generation sources (92). Challenges include the facts that Nigeria is yet to develop its biofuels program, a slow transition to expensive energy-efficient vehicles as about 60% of the country's population still lives below the poverty line (92), and slow adoption of ZEEVs as only about 60% of the Nigerian population has access to electricity (94). Moreover, transportation-related air pollution and carbon-dioxide emissions are worsened by the pervasive use of used motor vehicles (cars, trucks, lorries, buses, and motorbikes) in Nigeria (113, 114). In 2023, Nigeria's used car market of 500,000 sales (compared to 13,000 sales for brand-new vehicles), valued at $1.14 billion, constitutes 97.4% of available vehicles in the country (7). This market is estimated to grow by 8.9% in 2024 due to high inflation, declining GDP, and the spike in new car prices (7). Although the Nigeria Customs Service increased the import duty on vehicles from 39.45 to 39.62% to promote domestic manufacturing of vehicles and reduce imported cars, this has not reduced the dependence on used cars (115). Nigeria's import regulation limits used vehicle age to 15 years (116), however, this policy has failed to reduce the number of imported used vehicles (117). The complexities in the regional market for used vehicles in West Africa are such that trade restriction rules in Nigeria are often circumvented by the viable re-exportation of used cars from the alternative import routes from the neighboring countries of Benin and Togo Republics (117, 118). Benin and Togo have no age restriction for used vehicles, and they use a low-import tariff strategy to re-export to Nigeria (117, 118). Launched in January 2023, the National Vehicular Emission Control Programme (NVECP) provides annual testing of vehicles for toxic and GHG emissions (103). Sadly, the use of ZEEVs is uncommon in Nigeria due to high upfront costs, lack of charging infrastructure, lack of technical know-how, and political entrenchment of oil and gas (119). ZEEVs do not produce emissions irrespective of age, compared to internal combustive engine (ICE) vehicles, where emissions intensity can increase over time and more with a lack of maintenance (119). While Nigeria has the potential to import used ZEEVs, policymakers worry about the impact on Nigeria's crude oil exports (120). Nonetheless, deploying ZEEVs could lower emissions and remove the burden of petroleum subsidies Nigeria has to pay (120).
1.5 Nigeria's climate action
Nigeria is a party to the United Nations Framework Convention on Climate Change, which aims to limit the Earth's warming to 1.5 degrees Celsius (2.7 Fahrenheit). Nigeria commits to reducing carbon emissions by 20% by 2030 (121) and achieving net-zero carbon emissions by 2060 (122). Nigeria's commitment to global climate mandates includes policies like the Nationally Determined Contribution, National Climate Change Policy, National Climate Change Council, and Energy Transition Plan (123). However, Nigeria needs $1.9 trillion to achieve net-zero emissions in 2060, relying on international climate finance (123). The Conference of Parties (COP28) in Dubai agreed to four pillars: fast-tracking a just, orderly, and equitable energy transition from fossil fuel, fixing climate finance, focusing on people, lives and livelihoods, and underpinning everything with total inclusivity (124). At COP28, Nigeria secured over $400 million in commitment to the loss and damage fund and signed several commitments to establish solar panel and lithium battery manufacturing factories in Nigeria (125, 126). A lingering challenge remains that Nigeria is a fossil fuel-dependent developing country (FFDC) which rely on fossil fuel income and carbon intensive industries like the transport system. Nigeria's ability to successful transition will therefore depend on its capacity to diversify its assets and revenues (127). Nevertheless, Nigeria is already on the right tract for a just energy transition as the country has removed subsidies for fossil fuel consumption in 2023 (128).
2 Materials and methods
A comprehensive search of articles, abstracts and proceedings of conferences published in English in peer-reviewed academic journals and conferences was made. Electronic databases, including Medline, Embase, Scopus, Google Scholar, and African Journal Online (AJOL) were searched with no date restriction for ALL related works on the research interest. The keywords used for searches were “exposure to BTEX among petrol station attendants in Nigeria”; “exposure to volatile organic compounds at petrol stations in Nigeria”; “health hazards of petrol station attendants in Nigeria”; “knowledge of safety practices in filling stations in Nigeria”; “knowledge, attitude and practices on occupational health and safety in Nigeria's petrol stations”; “health effects of petrol fumes in Nigerian filling station attendants”; “petrol station attendants in Nigeria”; “symptoms among petrol station attendants in Nigeria”; “hazards among fuel station attendants in Nigeria” and “assessment of occupational safety and health in petrol stations in Nigeria”. When related articles were identified, the references cited by these articles were also searched for relevant articles.
Figure 2 depicts the diagrammatic sketch of the 81 reviewed articles. The first group was observational research that included studies of knowledge, attitude, and practices (KAPs) of occupational health and safety (OHS) in NPSs, for which questionnaires and checklists were used. The second was observational and analytical studies for which blood samples were taken for petrol fumes impacts on organ-systems of the Nigerian PSWs (haematologic, immunologic, hepatic, renal), or for which ultrasound scans were done, or physiologic (respiratory function indices) impacts were measured among the Nigerian PSWs. The third was those studies that measured ambient air quality in and around the NPSs.
Figure 2. A diagrammatic sketch of the reviewed 81 articles. SW, southwest; SS, southsouth; SE, southeast; NW, northwest; NC, northcentral; NE, northeast; OHS, occupational health and safety; NPS, Nigeria's petrol stations.
3 Results
3.1 Observational studies
Table 2 summarizes the findings of the observational studies.
Table 2. Summary of the observational studies.
Awareness of safety measures among PSWs varied from 63.2% in Sagamu (4) to 99.1% in Kaduna (131). The commonest safety measures in operations were signage of no-smoking in 92.4% (16) and fire extinguishers in 99% (135). Hand-washing after contact with petrol was also prominent in 73.5% of PSWs in Uyo (69).
Awareness of hazards among PSWs at the NPSs ranged from 24.4% in Benin (71) to 85.3% in Aba (70). Petrol fumes inhalation as a hazard among PSWs was recognized by 81% of the PSWs in Enugu (135), and by 7.4% of PSWs in Ile-Ife (129). Other hazards recognized were skin contamination by petrol (20%) (71), accidents at the petrol station (37.1%) (70), armed robbery (27.8%) (129), fuel spillage (90%) (15), and fire (94.4%) (129). In the Okafoagu et al. (16) study, PSWs recognize petrol fumes as a health hazard containing volatile organic compounds.
Of the health symptoms experienced by the PSWs, the common ones were headaches (53.6%) and low back pain (33.3%) (69), itchy eyes (48.2%) and headaches (22.4%) (129), and cough and difficulty in breathing (73). The work of Akodu et al. (130) was solely on the burden of low back pain (LBP) among PSWs in Lagos, and the majority (84.6%) experienced LBP over 12 months of working at the petrol stations. The majority (60%) of the respondents also acknowledged that prolonged standing was the activity that predisposed them to LBP (130).
Concerning awareness of personal protective equipment (PPE) among PSWs at NPSs, it was 25.4 and 30.7% in Sagamu (4) and in Uyo (69), respectively. Awareness about PPE availability was 75, 92, and 95.6% in Sokoto (16), Kaduna (131), and Benin (71), respectively. The use of PPE ranged from 7% in Uyo (69) to 89.4% in Aba (70). The common forms of PPE used were overalls (89.4%) (70) and boots (46.7%) (69). Two studies (70, 71) also reported that the regular use of PPE was dependent on workers' awareness of hazards (70), punishment for non-compliance with the use of PPE (70), educational status (71), and the number of years on the job (70, 71). Ahmed and his colleagues (15) in Minna also identified that safety standards are far better in petrol stations owned by major petroleum marketers (conglomerate) compared to petrol stations owned by independent petroleum marketers (IPMs). Lack of adequate staff training, accidents, and fire safety equipment maintenance was noted more commonly at petrol stations owned by IPMs (15).
The only qualitative study by Lawal in Ilorin (134) reported poor OHS management practices observed at the selected retail petrol stations (RPSs) and poor awareness and knowledge of health risks related to RPS among RPS owners. However, the public and environmental health officers know the health and environmental risks associated with RPSs. No statistically significant difference between the RPS employees and the general population's quality of life was noted on the SF-36 questionnaire.
3.2 Observational and analytical studies
Table 3 provides a synopsis of the observational and analytical studies. Among PSWs, Nnwanjo and Ojiako (144) in Owerri, Ogunneye et al. (150) in Ijebu-Ode, and Iyanda and Anetor (167) in Ibadan, reported elevated serum alkaline phosphatase (ALP), alanine aminotransferases (ALT) and aspartate aminotransferases (ASP). The serum liver enzymes also increased with years of exposure to petrol vapors (144, 150) and more among the female PSWs (181). Akinosun et al. (141) in Ibadan, on the other hand, reported a reduction of ALP among PSWs in their series.
Table 3. Summary of observational and analytical studies.
For most studies, the hematological indices were found to be lower among the PSWs compared to the controls that were not occupationally exposed to petrol liquid or vapors/fumes (142, 146, 153, 154, 158, 159, 162, 179). Contrariwise, Christian et al. (85) in Port-Harcourt, showed that white blood cells, granulocytes, lymphocytes, and monocytes were all elevated among PSWs compared to the controls. However, in Ibadan, Akintomiwa et al. (140) reported no significant difference in the blood levels of red blood cells, white blood cell, Hb and PCV between PSWs and the controls.
PSWs tended to have reduced pulmonary functions compared to the controls that were not occupationally exposed to petrol fumes/petroleum products (151, 155, 163, 171, 178). Anakwue et al. (168) described increased kidney echotexture among 21 of 36 PSWs in Enugu.
The four studies (136, 139, 143, 145) in Abeokuta, Southwest, described the effects of interventional 2 weeks ascorbic acid (500 mg daily) supplementation on some toxicities of chronic lead exposure in some occupationally exposed subjects including petrol station attendants. These studies reported that ascorbic acid supplementation can ameliorate chronic lead poisoning among occupationally exposed PSWs.
Umegbolu et al. (164) suggested the possibility of cancer risk in Awka, when the authors detected many micronuclei among 35 PSWs compared to controls not exposed to petrol. This risk was also found to increase beyond 2 years of exposure.
3.3 Air quality studies
Table 4 provides a summary of studies on air quality measurement. All the authors reported poor ambient air quality at the petrol stations. In addition, Olabisi (189) reported no known occupational health issues among the PSWs, although awareness of safety measures was poor at 10.0%. Oni and Ana (190) also reported a significantly lower mean peak expiratory flow rate (PEFR) among 100 PSWs in 20 petrol stations.
Table 4. Summary of air quality studies.
Only Ekpenyong et al. (68) in Uyo, measured and quantified BTEX in the breathing zones of female PSWs. Ekpenyong et al. (68) reported a higher mean concentration of BTEX compounds in female petrol attendants than in ambient air sampled a few kilometers from the gasoline stations. Ekpenyong et al. (68) also found that petrol vapors exposure significantly affected the menstrual cycle length and flow quantity. There were also persistent low serum oestradiol levels, and the mean benzene concentration among the PSWs was more than the threshold limit value for benzene (0.5 ppm). Okonkwo et al. (186) in Umuahia found that levels of volatile organic compounds, methane, carbon monoxide, nitric oxide exceeded the FEPA air quality guidelines. However, the particulate matters (PM1 and PM2.5) were found to be at concentrations within FEPA air guideline (193).
Lawal et al.'s (188) work in Kaduna, was a preliminary study to test the effectiveness of an improvised air sampler to capture VOCs and BTEX in ambient air around the petrol station. The researcher used commercially available activated charcoal as an adsorbent media, and they demonstrated the presence of BTEX in the ambient air of a petrol station, with the prospect of planning a more detailed study in the future.
4 Discussion
4.1 Occupational health and safety at Nigeria's petrol stations
The observational studies highlight that the knowledge, attitude, and practices (KAPs) of PSWs on workplace hazards, health problems, workplace accidents, safety measures, and PPE vary from one study setting to another. The observational and analytical studies suggest that exposure to petrol fumes/petroleum products of the PSWs results in adverse effects on the respiratory function indices and the hematologic, immunologic, hepatic, and renal systems of the PSWs. The air quality studies confirm the poor air quality of the NPSs, including the adverse effects of BTEX exposure on the reproductive system of female PSWs. Although the KAPs of OHS in NPSs vary from one study setting to another, generally, the consensus is that safety practices are poor and that awareness about hazards and PPE and using PPE is sub-optimal. The Nigerian PSWs are at an increased risk of exposure to BTEX, petrol fumes, and petrol liquid.
Possible reasons for poor safety practices and sub-optimal awareness about hazards and PPE, and the usage of PPE among PSWs in Nigeria include lack of adequate information about hazards at petrol stations and lack of knowledge about the capacities of PPE to reduce exposure to hazardous BTEX/petrol fumes/liquid petrol (69). Other reasons are inadequate training on safe practices before employment and ineffective law enforcement, which promotes the lackadaisical attitudes of employers toward OHS issues (131).
Although Ekpenyong et al. (68) document the toxicity of BTEX on menstruation and reproductive hormonal profiles, the researchers did not measure BTEX biomarkers that would have confirmed exposure to BTEX through multiple exposure pathways. Thus, their work suffered some drawbacks as workers' exposure to BTEX through the skin or gastrointestinal tract was not accounted for.
In Nigeria, because many filling stations fail to adhere to the stipulations of Nigeria's Department of Petroleum Resources (DPR), the regulatory body, an increasing number of PSWs are exposed to hazards at filling stations (129, 133). During the refueling of automobiles, the atmospheric concentration of gasoline vapor is between 20 and 200 ppm (194, 195). This amount is higher when a long queue of automobiles needs refueling (195), a common occurrence in Nigeria because of perennial fuel scarcity (4). Furthermore, exposure of the Nigerian PSWs to BTEX occurs from exhaust fumes from generator sets used in powering the petrol dispensing pumps. This is a common finding as the DPR requires that every filling station have one electric generator set for its normal operations (196). The need for a canopy over petrol pumps at the petrol station is another expectation of the DPR (196). Unfortunately, a canopy over the pumps increases the ambient flux of BTEX around the station (197). Moreover, the harsh economic situation in Nigeria forces most motorists to go about on near-empty petrol tanks with the attendant voluminous petrol fumes in the head-spaces when they come for refueling at the petrol stations (151, 171). In addition, Adeniyi (151) described a situation where petrol pump attendants are constrained to stay put by the vehicle as the vehicle tanks get filled, as most fuel pumps can only dispense petrol with the attendants holding the nozzles.
The effect of temperature on the vaporization of BTEX has been conflicting (52, 198, 199). While Periago et al. (199) and Kitwattanavong et al. (52) demonstrated that temperature was positively correlated to ambient BTEX concentrations in gasoline stations; Moolla et al. (198) reported a negative correlation between temperature and ambient BTEX concentrations in diesel station. Thus, although the concentration of BTEX is usually lower in warmer months (31, 41) and higher in colder winter months (31, 41), these findings may not be universal and many other variables have to be accounted for. Whereas, the cold temperature layer during winter hindered the dilution of BTEX and thus led to higher concentrations of BTEX in the atmosphere, while intense photochemical activity and dilution due to the increase in the mixing layer depth in summer led to lower concentrations of BTEX (41). Nigeria is in tropical Africa, with high temperatures for most of the year, hence, a strongly powered study that will test the effect of temperature and other meteorological conditions is warranted.
Lead (tetraethyl and tetramethyl lead) and BTEX are used as petrol antiknock and lubricating agents to improve machine efficiency (24). Although it was officially announced that lead had been phased out in Nigeria in 2004, the 2017 standard for Nigeria's gasoline still contains lead of 50 ppm and BTEX of 2% v/v (see text footnote 2). Most lead is emitted from motor vehicles as inorganic particles (200), and leaded gasoline causes more exposure to lead than any other known source (201). Furthermore, lead and BTEX in gasoline cause overlapping health hazards, including gastrointestinal and hematological disturbances, hepatic and renal damage, hypertension and neurological disorders (21, 200, 202). The acute and chronic health symptoms of lead and BTEX are indistinguishable from each other, and attribution would have to be done by specific measurements of lead and BTEX among occupationally exposed workers. Acute lead exposure may cause gastrointestinal disturbances (anorexia, nausea, vomiting, abdominal pain), hepatic and renal damage, hypertension and neurological effects (malaise, drowsiness, encephalopathy) that may lead to convulsions and death (203). Chronic lead exposure effects include hematological effects (anemia), neurological disturbances (headache, irritability, depression, lethargy, convulsions, muscle weakness, ataxia, tremors and impaired hearing), gastrointestinal disorders (abdominal colic), and kidney dysfunction (204). These symptoms overlap with those shown in Table 1, resulting from acute and chronic exposures to BTEX (43–46). Thus, the works of Alasia et al. (83), Bambgose et al. (84), Christian et al. (85), Emokpae and Oyakhire (86), Eze et al. (87), Obi et al. (88), and Onuegbu et al. (89) which assessed the association of blood levels of lead and some clinical and biochemical changes among workers occupationally exposed to lead should be interpreted cautiously, as confounding exposure to BTEX cannot be excluded. Nevertheless, while children are especially vulnerable to the neurotoxic effects of lead (204), BTEX are the most commonly exposed VOCs among workers at petrol stations (21, 205). In addition, compared to benzene, which the IARC has classified as human carcinogen Group 1 causing acute myeloid leukemia and acute non-lymphocytic leukemia (43), inorganic lead compounds are probably carcinogenic to humans (Group 2A) (206) and organic lead are not classifiable in human carcinogenicity (Group 3) (206). Thus, while efforts to completely phase out lead in gasoline in Nigeria continue, future research efforts on BTEX exposures at NPSs should be considered favorably, as benzene remains the most toxic chemical additive in gasoline (207, 208).
4.2 Challenges of safeguarding occupational health and safety at Nigeria's petrol stations
Safeguarding the OHS of workers at NPSs is dependent on two prerequisites. First, there will be regulations and policies to guide the OHS of workers at the petrol stations. Second, there would be efficient and effective enforcement modalities of regulations and policies on OHS. Regarding the OHS of workers in NPSs, the two prerequisites are sub-optimal (72, 209). The Nigerian constitution statutorily empowers the DPR to ensure compliance with the oil and gas industry's regulations, guidelines, and laws (196).
Furthermore, since August 2021, and backed by Nigeria's Petroleum Industry Act of 2021 (210), the Petroleum Products Pricing Regulatory Agency (PPPRA) and the Petroleum Equalization Fund Management Board (PEFMB) have been merged with the Midstream and the Downstream Divisions of the DPR to form the Nigerian Midstream and Downstream Petroleum Regulatory Authority (NMDPRA) (210). The former DPR now operates under the NMDPRA (210). The NMDPRA, known as “The Authority”, statutorily provides a legal, governance, regulatory and fiscal framework for the Nigerian Petroleum Industry (210). The NPSs are retail outlets for petroleum products and they operate under the Downstream Division of the NMDPRA. The objectives of the PIA are to provide for the safety standards to be observed during midstream and downstream petroleum operations; (b) regulate safety and occupational health in Nigerian midstream and downstream petroleum operations; (c) set out the permits, authorizations, and fees for such midstream and downstream petroleum operations; and (d) provide sanctions, penalties, and administrative fines for failure to comply with these Regulations (210).
Table 5 shows the DPR guidelines regarding the sitting and construction of petrol stations in Nigeria (196). The DPR introduced the Minimum Industry Safety Training for Downstream Operations (MISTDO) as part of the Safety Audit Clearance policy launched to drive safety in the downstream sector. MISTDO is the basic safety training that is compulsory for all workers in the downstream sector of the Nigerian oil and gas industry (211). Regardless of the extant legislation and regulations on OHS in Nigeria, the consensus by observers is that OHS still needs improvement (72). The enforcement of the DPR guidelines needs thorough institutional improvements (212, 213). Owners of petrol stations have refused to adhere to proper land uses characterized by careless constructions, abnormally chaotic locations of petrol stations in residential areas, and over-concentration of petrol stations in one part of the urban cities, infractions that pose significant hazards to the health of workers, motorists and the people residing in surrounding environments to the petrol stations (212, 213). The poor sitting conditions of Nigeria's petrol stations also cause traffic congestion, air pollution, and fire hazards (72, 214). The abysmal state of OHS in Nigeria is attributable to the poor enforcement of OHS regulations and the need for more content and scope of the extant OHS regulations (215, 216).
Table 5. The Department of Petroleum Resources guidelines on construction of petrol stations in Nigeria (196).
In general, the gravity of penalties stipulated by OHS laws in Nigeria is insignificant and cannot deter offenders from fouling the regulations (216, 217). For example, the penalty stipulated by the Workman's Compensation Act is as low as 2000 Naira (2.53 United States Dollars, at 2023 rates of 0.0013 USD to 1 Naira) or the premium payable for 1 year (whichever is greater) when an employer fails to insure the employees against death or injuries (217). Regarding the Midstream and Downstream Petroleum sectors, the penalty is stiffer. A licensee who fails to comply with any of the provisions of the safety regulations shall, in addition to the sanctions, fines and penalties contained in the Act, be liable to an administrative penalty of not more than USD 250,000 (210). Any permit or authorization granted to that licensee or holder may be suspended or revoked (210). In addition, a manager who fails to comply or ensure compliance with these Regulations is liable to an administrative penalty issued by the Authority of not more than N5,000,000, an equivalent of 6,314 USD (210).
Furthermore, Nigeria's slow and ineffective judicial process discourages workers from seeking redress in incidents that infract OHS (217). Moreover, because the labor supply often overshadows demands, employers tend to become overlords with a penchant for disregarding the extant regulation on OHS (217). This power imbalance also makes it difficult for workers to demand their rights in the workplace (217). Another barrier to enforcement is ignorance about workers' rights and privileges. Both employees and employers need to become more familiar with the Factories Act and other extant laws that define OHS, rights, privileges, and expectations at the workplace (217).
Apart from the DPR, other pieces of Nigerian legislation safeguard Nigerian workers' safety, health, and welfare at petrol stations. These legislations include the Constitution of the Federal Republic of Nigeria 1999, the Labour Act of 2004, the Factories Act of 2004, the Employee Compensation Act of 2010, the Minerals Oil Safety Regulation of 1999, and the Harmful Waste Act of 1990 (134, 217). However, regardless of these extant Acts, Laws, and Regulations on OHS in Nigeria, the consensus by reviewers is that the OHS of Nigerian workers is still poor, and by extension, this includes Nigerians working at petrol stations (72, 134, 217).
4.3 Factors that determine the vulnerability of petrol station workers to petrol/BTEX exposure at petrol stations
In occupational epidemiology, the vulnerability of PSWs' exposure to petrol fumes or petrol liquid or BTEX can be contextualized as a dependent outcome or variable (personal monitoring or biological markers of BTEX) and the independent but interrelated risk factors. These independent factors determine PSWs' exposure to chemical hazards, including petrol/BTEX. The literature review of studies on occupational exposure to petrol or other petrochemicals containing BTEX by the authors identify seven risk factors of petrol station workers that determine their vulnerability to petrol/BTEX exposure at petrol stations as shown in Figure 3.
Figure 3. The seven risk factors that determine the vulnerability of petrol station workers to petrol/BTEX exposure at petrol stations. OHS, occupational health and safety. *Presence of confounding environmental source of BTEX: means of transport to work (walk, bicycle, motorcycle, commercial vehicle, personal vehicle), time spent in gelling to work, exposure to tobacco smoke, alcohol consumption, household of the PSWs including beating and cooking activities (gas, kerosene, firewood, animal dung), building finishing: inside painted or not, household storage of petrol, paint, pesticides, fertilizers and herbicides, household use of generator set, household use of varnishes, finger nail polish, glues at home, cleansing agents, and shoe polish, engagement in other jobs apart from working at petrol stations (painter, vulcanizer, mechanics, farmer).
Table 6 depicts some studies that describe the risk factors that may determine the vulnerability of petrol station workers to petrol/BTEX exposure at petrol stations.
Table 6. Studies of risk factors that may determine the vulnerability of petrol station workers to petrol/BTEX exposure at the petrol stations.
Efforts to reduce human exposure to BTEX have included reducing BTEX emissions at petrol stations in Europe by adopting vapor recovery systems (VRS) and by avoiding vapor losses during fuel transfer (228); restricting benzene composition in gasoline in Europe to 1% (v/v) (18) and to 0.62% (v/v) in the United States (19); and by standardizing benzene concentration in ambient outdoor air in Europe to 5 μg.m−3 (229). Table 7 shows the OELs of some professional institutions and countries (61). Unfortunately, there are no known national standards for OELs to BTEX in Nigeria (16). Instead, Nigeria's National Environmental Regulations on Air Quality Control (230) has some air quality standards for criteria for pollutants and air toxics, as shown in Table 8. Thus, PSWs in Nigeria are continuously being exposed to a work environment that exposes them to unmitigated levels of BTEX/petrol vapors.
Table 7. Occupational existing limits of benzene, toluene, ethylbenzene and xylene of some professional institutions and countries (61).
Table 8. Ambient air quality standards for criteria pollutants and air toxics in Nigeria (230).
4.4 Protective strategies against exposure to BTEX/petroleum products at petrol stations
Providing protective and interventional strategies against BTEX exposure at the NPSs can adapt from the measures applied in other built environments (231). These strategies include administrative, environmental/engineering, and personal protective measures (231). Administrative controls are policies and procedures put in place and implemented by petrol station managers/DPR that will reduce the vulnerability of PSWs to BTEX exposure. Environmental controls at the petrol station focus on engineering strategies that collect and prevent BTEX and other vapors from escaping and polluting the atmosphere (vapor recovering), as well as those designs that destroy the collected BTEX and other vapors (vapor destroying). Vapor recovery occurs in two stages (227, 232). The first stage is when underground storage tanks are refilled by tanker trucks. The second stage is when motor vehicles' tanks are being refueled (227, 232). At both stages, gasoline vapors in the head-spaces of empty or partially empty storage tanks and vehicles' tanks rise and pollute the atmosphere as liquid petrol is transferred into the tanks (227, 232). USEPA Stage I recovers petrol vapors in the first stage using two hoses (227, 232). The first hose transfers gasoline from the tanker truck to the storage tank (227, 232). The second hose simultaneously collects gasoline vapors being displaced out of the storage tank and back to the empty tanker truck (227, 232). The displaced vapors can then be collected for incineration, converted to liquid, and returned to the storage tank (227, 232). USEPA Stage II is a balance recovery system that uses a vapor recovery nozzle with a guard at the root of the filling pipe and recovery holes on the filling nozzle pipe. The guard fits tightly to the vehicle's tank preventing the escape of displaced gasoline vapors from the head-space during refueling. The recovery holes return gasoline vapors into the underground tank. Stage II control cuts the escape of gasoline vapor emissions by up to 88–92% (227, 232).
Personal protection controls are used in high-risk environments and emergency scenarios as the last resort where administrative and environmental controls cannot adequately offer protection (231). Thus, while personal protection controls may be the most visible form of strategy (appearing at the 'tip of the iceberg), they are not the most important. Examples of personal protection include the use of PPE and personal hygiene. Figure 4 summarizes the strategies to control exposure to BTEX in Nigeria's petrol station-built work environment. Unfortunately, until a safer substance is available to serve as an alternative additive for petroleum products, physically removing (elimination) or replacing (substitution), BTEX cannot form an integral part of the hierarchy of controls of exposures to BTEX at this time.
Figure 4. Hierarchy of control measures to protect workers at petrol stations. PPE, personal protective equipment; DPR, department of petroleum resources, *while personal control may be at the “tip of the iceberg”, the environmental control at the base is far more important.
4.5 Research gaps and future research directions
Despite the available research on the OHS of PSWs at NPS, further research on BTEX exposure and pollution in Nigeria must be emphasized. Table 9 depicts some areas of research that need to be developed to improve public health safety from BTEX pollution in Nigeria.
Table 9. Highlights of future research areas and research focus on BTEX pollution in Nigeria.
Controlling air pollution from BTEX and other hazardous air pollutants is an essential component of OHS, which forms an integral part of attaining the Sustainable Development Goals (SDG) 3 and 11 (233), of which the WHO is the custodian (234). The targets of the SDG relevant to ambient air pollution include SDG target 3.9.1 (it calls for a substantial reduction in deaths and illnesses from air pollution) and SDG target 11.6.2 (it aims to reduce the environmental impact of cities by improving air quality) (234).
5 Conclusion
The available literature revealed that OHS knowledge, attitudes, and practices in NPSs vary from one Nigeria's study setting to another. Generally, the consensus is that safety practices, awareness about hazards and PPE, and the usage of PPE among PSWs failed to live up to expectations. The Nigerian PSWs are at an increased risk of exposure to BTEX, petrol vapor, and petrol liquid. Currently, regulatory bodies' effectiveness and accountability in enforcing OHS regulations in NPSs leave much to be desired. Understanding the OHS of NPSs would inform future initiatives, policies, and regulations that would promote the health and safety of workers at NPSs. However, future studies need to be conducted that will describe and safeguard PSWs and other Nigerians who are occupationally exposed to BTEX pollution. Controlling air pollution from BTEX and other hazardous air pollutants is an essential component of OHS and integral to attaining the Sustainable Development Goals (SDG) 3, 7, and 11.
6 Limitations of study
In this study, it is essential to remember that while studies on OHS at NPS are reported based on the six geopolitical regions of Nigeria, we need to be cautious in interpreting and drawing conclusions from them. It is essential to note that while the results of these studies are factual for the specific settings where they were conducted, caution in generalizing the results to the entire geopolitical region of Nigeria needs to be emphasized.
Author contributions
EA: Conceptualization, Data curation, Formal analysis, Methodology, Resources, Writing—original draft, Writing—review & editing. ZN: Conceptualization, Methodology, Resources, Supervision, Writing—review & editing. CW: Conceptualization, Funding acquisition, Project administration, Resources, Supervision, Writing—review & editing.
Funding
The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by the Petroleum Technology Development Fund, Nigeria (PTDF/ED/OSS/PHD/AEA/1831/20; 20PHD139, 2020). The PTDF did not participate in study design; in the collection, analysis, and interpretation of data; in the writing of the report; and in the decision to submit the article for publication.
Acknowledgments
EA is an Overseas Scholar of the Petroleum Technology Development Fund (PTDF), Nigeria. The PTDF is hereby acknowledged.
Conflict of interest
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Publisher's note
All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.
Footnotes
1. ^Nigerian Industrial Standard (NIS 948-2017)(2017). Standard for Diesel Fuel (AGO). file:///D:/NIS-948-2017.pdf.
2. ^Nigerian Industrial Standard (NIS 116:2017). (2017). Standard for Premium Motor Spirit (Petrol). file:///D:/NIS-116-2017.pdf [accessed June 2, 2022].
3. ^Nigeria-The World Factbook (2023). Available online at: https://www.cia.gov/the-world-factbook/countries/nigeria/ (accessed January 2, 2023).
References
1. NBS. Petroleum products imports and consumption (Truck out)statistics.Petroleum_Products_Importation_and_Consumption_(Truck_Out)_–_Q1 2020.cdr (nigerianstat.gov.ng). National Bereau of Statistics (2020).
2. NOGIAR. Nigerian Oil and Gas Industry Annual Report (2018). Available online at: https://www.nuprc.gov.ng/wp-content/uploads/2020/01/2018-NOGIAR-1.pdf (accessed October 6, 2022).
3. Anetor JI, Adigun TO, Bolajoko EB. Deranged haembiosynthetic pathway in gasoline dispensers in Nigeria: Implications for risk of myeloproliferative disorders and chemoprevention. Am J Biopharm Pharm Sci. (2022) 2:2. doi: 10.25259/AJBPS_10_2021
4. Ogunkoya JO, Bamidele EF, Ngubor TD, Uka AT, Ani FC, Ogunkoya OA. Assessment of safety practices and use of personal protective equipment among petrol pump attendants within Sagamu metropolis in Ogun State Nigeria. Int J Health Safety Environ. (2021) 7:801–9.
5. Oladipo O. Nigeria's Daily Petrol Consumption Hits a Record High of 93 Million Litres (2021). Available online at: https://businessday.ng/energy/oilandgas/article/nigerias-daily-petrol-consumption-hits-record-high-of-93m-litres (accessed August 11, 2022).
6. RTD. National Bureau of Statistics, Nigeria. Road Transport Data (2018). Available online at: https://nigerianstat.gov.ng/download/813 (accessed March 3, 2022).
7. Umeh J. Nigeria's Market for Used Cars Hit 500, 000 Per Year (2023). Available online at: https://www.vanguardngr.com/2023/07/nigerias-market-for-used-cars-hit-500000-per-year/ (accessed February 16, 2024).
9. Pérez-Martínez P, Miranda R, Andrade M, Kumar P. Air quality and fossil fuel driven transportation in the Metropolitan Area of São Paulo. Transp ResInterdiscipPerspect. (2020) 5:100137. doi: 10.1016/j.trip.2020.100137
10. Rith M, Roquel KIDZ, Lopez NSA, Fillone AM, Biona JBMM. Towards more sustainable transport in Metro Manila: a case study of household vehicle ownership and energy consumption. Transp Res Interdiscip Perspect. (2020) 6:100163. doi: 10.1016/j.trip.2020.100163
11. Udeozor OS, Nzeako AN. The implications of importation of used vehicles on the environment. Glob J Res Eng Automot Eng. (2012) 12:1-B.
12. Adewuyi OB, Kiptoo MK, Afolayan AF, Amara T, Alawode OI, Senjyu T. Challenges and prospects of Nigeria's sustainable energy transition with lessons from other countries' experiences. Energy. Rep. (2020) 6:993–1009. doi: 10.1016/j.egyr.2020.04.022
13. Emetere ME, Agubo O, Chikwendu L. Erratic electric power challenges in Africa and the way forward via the adoption of human biogas resources. Energy Explor Exploit. (2021) 39:1349–77. doi: 10.1177/01445987211003678
14. Akujor CE, Uzowuru EE, Abubakar SS, Amakom CM. Decarbonisation of the transport sector in Nigeria. Environ Health Insights. (2022) 23:11786302221125039. doi: 10.1177/11786302221125039
15. Ahmed S, AbdulRahman AS, Kovo AS, Ibrahim S, Okoro EO, Agbo AA. Health, risk and safety of petrol Stations in Minna Town: an overview. World Appl Sci J. (2014) 32:655–60.
16. Okafoagu NC, Oche MO, Gana GJ, Ango JT, Yunusa EU. Knowledge of occupational hazards and safety practices among petrol station attendants in Sokoto, metropolis, Sokoto State, Nigeria. J Occup Health Epidemiol. (2017) 6:122–6. doi: 10.29252/johe.6.3.122
17. NBS SMEDAN. Survey Report on the Micro, Small and Medium Enterprises in Nigeria. National Bureau of Statistics (NBS) and Small and Medium Enterprices Development Agency (SMEDAN) (2010).
18. Correa SM, Arbilla G, Marques MRC, Oliveira KMPG. The impact of BTEX emissions from gas stations into the atmosphere. Atmospheric Pollut Res. (2012) 3:163–9. doi: 10.5094/APR.2012.016
19. USEPA. Gasoline Standards; Gasoline Mobile Source Air Toxics (2019). Available online at: ://www.epa.gov/ gasoline-standards/gasoline-mobile-source-air-toxics (accessed January 18, 2019).
20. Al-Harbi M, Alhajri I, AlAwadhi A, Whalen JK. Health symptoms associated with occupational exposure of gasoline station workers to BTEX compounds. Atmospheric Environ. (2020) 241:117847. doi: 10.1016/j.atmosenv.2020.117847
21. Kuranchie FA, Angnunavuri PN, Attiogbe F, Nerquaye-Tetteh EN. Occupational exposure of benzene, toluene, ethylbenzene and xylene (BTEX) to pump attendants in Ghana: Implications for policy guidance. Cogent Environ Sci. (2019) 5:1603418. doi: 10.1080/23311843.2019.1603418
22. Montero-Montoya R, Lopez-Vargas R, Arellano-Aguilar O. Volatile organic compounds in air: sources, distribution, exposure and associated illnesses in children. Ann Glob Health. (2018) 84:225–38. doi: 10.29024/aogh.910
23. Fakinle BS, Olalekan AP, Odekanle EL, Bakut CB, Ogundokun RO, Sonibare JA, et al. Assessment of the contribution of hazardous air pollutants from Nigeria's petroleum refineries to ambient air quality. Part 1. Cogent Eng. (2021) 8:1870792. doi: 10.1080/23311916.2021.1947007
24. Stolark J. Fact Sheet: a Brief History of Octane in Gasoline, From Lead to Ethanol. Washington, DC: Environmental and Energy Study Institute (2016).
25. Leusch F, Bartkow M. A short Primer on Benzene, Toluene, Ethylbenzene, Xylene (BTEX) in the Environment and in Hydraulic Fracturing Fluids (2010). Available online at: https://environment.des.qld.gov.au/__data/assets/pdf_file/0020/87140/btex-report.pdf (accessed January 4, 2022).
26. Afshari A, Schuch F, Marpu P. Estimation of the traffic related anthropogenic heat release using BTEX measurements-A case study in Abu Dhabi. Urban Climate. (2018) 24:311–25. doi: 10.1016/j.uclim.2017.02.001
27. Bolden AL, Kwiatkowski CF, Colborn T. New look at BTEX: are ambient levels a problem. Environ Sci Technol. (2015) 49:5261–6. doi: 10.1021/es505316f
28. Mann HS, Crump D, Brown V. Personal exposure to benzene and the influence of attached and integral garages. J R Soc Promot Health. (2001) 121:38–46. doi: 10.1177/146642400112100109
29. Safar AN, Yassin MF, Hamoda MF. Indoor and outdoor air concentrations of volatile organic compounds in schools within different 1006 urban areas. Int J Environ Sci Technol. (2019) 16:2831–8. doi: 10.1007/s13762-018-1869-6
30. Lim SK, Shin HS, Yoon KS, Kwack SJ, Um YM, Hyeon JH, et al. Risk assessment of volatile organic compounds benzene, toluene, ethylbenzene, and xylene (BTEX) in consumer products. J Toxicol Environ Health A. (2014) 77:1502–21. doi: 10.1080/15287394.2014.955905
31. Yu B, Yuan Z, Yu Z, Xue-song F. BTEX in the environment: an update on sources, fate, distribution, pretreatment, analysis, and removal techniques. Chem Eng J. (2022) 435:134825. doi: 10.1016/j.cej.2022.134825
32. Sahu L. Volatile organic compounds and their measurements in the troposphere. Curr Sci. (2012) 102:1645–9.
33. USEPA. Initial list of hazardous air pollutants with modifications. Initial List of Hazardous Air Pollutants with Modifications (2019).
34. Costa-Gómez I, Caracena AB, Durán-Amor M, Banon D. BTEX proportions as an indicator of benzene hotspots and dispersion tends in cities where sea and land breezes dominate. Air Qual Atmos Health. (2023) 16:733–44. doi: 10.1007/s11869-023-01306-3
35. Hajizadeh Y, Mokhtari M, Faraji M, Mohammadi A, Nemati S, Ghanbari R, et al. Trends of BTEX in the central urban area of Iran: a preliminary study of photochemical ozone pollution and health risk assessment. Atmos Pollut Res. (2018) 9:220–9. doi: 10.1016/j.apr.2017.09.005
36. Dehghani M, Fazlzadeh M, Sorooshian A, Tabatabaee HR, Miri M, Baghani AN, et al. Characteristics and health effects of BTEX in a hot spot for urban pollution. Ecotoxicol Environ Saf. (2018) 155:133–43. doi: 10.1016/j.ecoenv.2018.02.065
37. Gelencsér A, Siszler K, Hlavay J. Toluene–benzene concentration ratio as a tool for characterizing the distance from vehicular emission sources. Environ Sci Technol. (1997) 31:2869–72. doi: 10.1021/es970004c
38. Atkinson R, Carter WPL. Kinetics and mechanisms of the gasphase reactions of ozone with organic compounds under atmospheric conditions. Chem Rev. (1984) 84:437–70. doi: 10.1021/cr00063a002
39. Atkinson R, Darnall KR, Lloyd AC, Winer AM, Pitts JN. Kinetics and mechanisms of the reactions of the hydroxyl radical with organic compounds in the gas phase. In:Pitts JM Jr, Hammond GS, Gollnick K, Grosjean D, , editors. Advances in Photochemistry. Wiley-Blackwell (2007). p. 375–488.
40. Jun-lin W, Yue-si W, Fang-kun Z. Characterizations of volatile organic compounds during high ozone episodes in Beijing, China. Environ Monit Assess. (2012) 184:1879–89. doi: 10.1007/s10661-011-2086-7
41. Jiang Z, Grosselin B, Daele V, Mellouki A, Mu Y. Seasonal and diurnal variations of BTEX compounds in the semi-urban environment of Orleans, France. Sci Total Environ. (2017) 57:1659–64. doi: 10.1016/j.scitotenv.2016.08.214
42. Abbasi F, Pasalari H, Delgado-Saborit JM, Rafiee A, Abbasi A, Hoseini M. Characterization and risk assessment of BTEX in ambient air of a Middle Eastern City. Process Saf Environ Prot. (2020 139:98–105. doi: 10.1016/j.psep.2020.03.019
43. Benzene (2023). Available online at: https://pubchem.ncbi.nlm.nih.gov/compound/benzene (accessed March 3, 2023).
44. Ethylbenzene. (2023). Ethylbenzene. https://pubchem.ncbi.nlm.nih.gov/compound/ethylbenzene (accessed March 3, 2023).
45. Toluene (2023). https://pubchem.ncbi.nlm.nih.gov/compound/toluene (accessed March 3, 2023).
46. Xylene (2023). https://pubchem.ncbi.nlm.nih.gov/compound/xylene (accessed March 3, 2023).
47. Alghamdi MA, Khoder M, Abdelmaksoud AS, Harrison RM, Hussein T, Lihavainen H, et al. Seasonal and diurnal variations of BTEX and their potential for ozone formation in the urban background atmosphere of the Coastal City Jeddah, Saudi Arabia. Air Qual Atmos Health. (2014) 7:467–80. doi: 10.1007/s11869-014-0263-x
48. Masih A, Lall AS, Taneja A, Singhvi R. Exposure profiles, seasonal variation and health risk assessment of BTEX in indoor air of homes at different microenvironments of a terai province of northern India. Chemosphere. (2017) 176:8–17. doi: 10.1016/j.chemosphere.2017.02.105
49. Zheng H, Kong S, Xing X, Mao Y, Hu T, Ding Y, et al. Monitoring of volatile organic compounds (VOCs) from an oil and gas station in northwest China for 1 year. Atmos Chem Phys. (2018) 18:4567–95. doi: 10.5194/acp-18-4567-2018
50. Zhang JJ, Wei Y, Fang Z. Ozone pollution: a major health hazard worldwide. Front Immunol. (2019) 10:2518. doi: 10.3389/fimmu.2019.02518
51. Heibati B, Pollitt KJG, Karimi A, Charati JY, Ducatman A, Shokrzadeh M, et al. BTEX exposure assessment and quantitative risk assessment among petroleum product distributors. Ecotoxicol Environ Saf. (2017) 144:445–9. doi: 10.1016/j.ecoenv.2017.06.055
52. Kitwattanavong M, Prueksasit T, Morknoy D, Tunsaringkarn T, Siriwong W. Health risk assessment of petrol station workers in the Inner City of Bangkok, Thailand, to the exposure to BTEX and carbonyl compounds by inhalation. Hum Ecol Risk Assess. (2013) 19:6. doi: 10.1080/10807039.2012.685814
53. Alves LP, Vieira DS, Nunes LSS, Cruz LPS, Reis ACS, Gomes IVS, et al. Relationship between symptoms, use of PPE and habits related to occupational exposure to BTEX compounds in workers of gas stations in Bahia, Brazil. J Environ Prot Ecol. (2017) 8:650–61. doi: 10.4236/jep.2017.85042
54. Campo L, Rossella F, Mercadante R, Fustinoni S. Exposure to BTEX and ethers in petrol station attendants and proposal of biological exposure equivalents for urinary benzene and MTBE. Ann Occup Hyg. (2016) 60:318–33. doi: 10.1093/annhyg/mev083
55. Cezar-vaz MR, Rocha LP, Bonow CA, Silva MRS, Vaz JC, Cardoso LS. Risk perception and occupational accidents: a study of gas station workers in Southern Brazil. Int J Environ Res Public Health. (2012) 9:2362–7. doi: 10.3390/ijerph9072362
56. Cruz LPS, Alves LP, Santos AVS, Esteves MB, Gomes ÍVS. Assessment of BTEX concentrations in air ambient of gas stations using passive sampling and the health risks for workers. J Environ Prot. (2017) 4:12–25. doi: 10.4236/jep.2017.81002
57. Jo WK, Song KB. Exposure to volatile organic compounds for individuals with occupations associated with potential exposure to motor vehicle exhaust and/or gasoline vapor emissions. Sci Total Environ 269. (2001) 25–37. doi: 10.1016/S0048-9697(00)00774-9
58. John MT. A Case Study on the Common Health Effects of Petroleum Product (Petrol, Diesel and Kerosene) on Fuel Retail Attendants in Madang, Lae and Goroka Province. Madang (Bsc thesis). Divine Word University, Madang, Papua New Guinea (2016).
59. Majumdar D, Dutta C, Mukherjee AK, Sen S. Source apportionment of VOCs at the petrol pumps in Kolkata, India; exposure of workers and assessment of associated health risk. Transp Res. (2008) 13:524–30. doi: 10.1016/j.trd.2008.09.011
60. Mehrjerdi MHM, Tahmasebi N, FiroozAbadi AB, Fallahzadeh H, Esmaielian S, Soltanizadeh K. The investigation of exposure to benzene, toluene, ethylbenzene and xylene (BTEX) with solid phase microextr action method in gas station in Yazd province. Iranian South Med J. (2014) 16:419–27.
61. Rahimpoor R, Sarvi F, Rahimnejad S, Ibrahimi SM. Occupational exposure to BTEX and styrene in West Asian countries: a brief review of current state and limits. Arhza Higijenu Rada i Toksikologiju. (2022) 73:107–18. doi: 10.2478/aiht-2022-73-3634
62. Rastkari N, Izadpanah F, Yunesian M. Exposure to benzene in gas station workers: Environmental and biological monitoring. Iranian J Health Environ. (2015) 8:163–70.
63. Santiago F, Alves G, Otero UB, Tabalipa MM, Scherrer LR, Kosyakova N, et al. Monitoring of gas station attendants exposure to benzene, toluene, xylene (BTX) using three-color chromosome painting. Mol Cytogenet. (2014) 7:1–7. doi: 10.1186/1755-8166-7-15
64. Tunsaringkarn T, Siriwong W, Rungsiyothin A, Nopparatbundit S. Occupational exposure of gasoline station workers to BTEX compounds in Bangkok, Thailand. Int J Occup Environ Med. (2012) 3:117–25.
65. Chaiklieng S, Suggaravetsiri P, Autrup H. Risk assessment on benzene exposure among gasoline station workers. Int J Environ Res Public Health. (2019) 16:2545. doi: 10.3390/ijerph16142545
66. Moolla R, Curtis CJ, Knight J. Occupational exposure of diesel station workers to BTEX compounds at a bus depot. Int J Environ Res Public Health. (2015) 12:4101–15. doi: 10.3390/ijerph120404101
67. Varrella S. Contribution of Oil Sector to GDP in Nigeria 2018-2021 (2021). Available online at: https://www.statistica.com/statistics/1 (accessed December 1, 2021).
68. Ekpenyong CE, Davies K, Daniel N. Effects of gasoline inhalation on menstrual characteristics and the hormonal profile of female petrol pump workers. J Environ Prot. (2013) 4:65–73. doi: 10.4236/jep.2013.48A1009
69. Johnson OE, Umoren QM. Assessment of occupational hazards, health problems and safety practices of petrol station attendants in Uyo, Nigeria. J Community Med Prim Health Care. (2018) 30:47–57.
70. Aguwa EN, Sussan SU, Asuzu MC. Assessment of workplace accidents and risk reduction mechanisms among filling station pump operators in Aba, Southeast Nigeria', Occup. Environ Health J. (2014) 3:17–25. doi: 10.4103/1119-3077.130229
71. Emokpae MA, Oyakhire FO, Kolawole JJ. Awareness of health hazards and use of personal protective equipment among fuel pump attendants in Benin City, Nigeria. Nigerian J Exp Clin Biosci. (2020) 8:128–33. doi: 10.4103/njecp.njecp_35_20
72. Umeokafor N, Isaac D, Jones K, Umeadi B. Enforcement of occupational safety and health regulations in Nigeria: an exploration. Eur Sci J. (2014) 3:93–104.
73. Moke EG. Adherence to safety practices and the effect of petroleum products on petrol station attendants in Abraka, Delta State, Nigeria. J Appl Sci Environ Manage. (2019) 23:2009–12. doi: 10.4314/jasem.v23i11.16
74. Akintonwa A, Oladele TT. Health effects of exposure to hydrocarbon on petrol filling station attendants in Lagos. Nig Q J Hosp Med. (2003) 13:88–92. doi: 10.4314/nqjhm.v13i1.12521
75. Awojulugbe O. Factsheet: What You Need to Know About Nigeria's Ailing Refineries and Their Perennial Repairs. Lagos: Academic Publishing Centre (2021).
76. Ogbuigwe A. Refning in Nigeria: history, challenges and prospects. App Petrochem Res. (2018) 8:181–192. doi: 10.1007/s13203-018-0211-z
77. Geniat M, Harjono M, Missbach A, Viredaz G-V. Dirty Diesel. How Swiss Traders Flood Africa With Toxic Fuels. A Public Eye Investigation. Lausanne: Public Eye.2016-DirtyDiesel-Public-Eye-Investigation.pdf (2016).
78. Yoboue M, Kaufman J. Inside the dirty fuels campaign: lessons for business and human rights. Bus Hum Rights J. (2018) 3:291−7. doi: 10.1017/bhj.2018.7
79. Ross A. Five West African Countries Ban “Dirty Diesel” from Europe, The Guardian (2016). Available online at: https://www.theguardian.com/global-development/2016/dec/06/five-west-african-countries-ban-dirty-diesel-from-europe-nigeria-ghana (accessed December 6, 2016).
80. Addeh E. Nigeria to Get Better Quality of Fuel as Belgium Plans to Ban Dirty Products Export to Africa. Lagos: Arise Media Group (2023).
81. Galadima A, Okoronkwo MU, Luter L. Petrol in Nigeria: a fuel or a killer? “Is shift to hydroisomerisation not overdue?” Elixir Pollution. (2012) 12:6893–7.
82. National Conference on the Phase-out of Leaded Gasoline in Nigeria Abuja Nigeria (2001). Available online at: https://www.esmap.org/sites/default/files/esmap-files/Rpt_Gasoline_in_NigeriaAbujaWP6.pdf
83. Alasia DD, Emem-Chioma PC, Wokoma FS. Occupational and Environmental Lead Exposure in Port Harcourt, Nigeria: analysis of its association with renal function indices. Niger J Med. (2010) 19:407–14. doi: 10.4314/njm.v19i4.61965
84. Bamgbose JT, Ademuyiwa O, Bamgbose O. Blood Lead level and its effects on occupationally exposed workers in Abeokuta, Nigeria. Catrina. (2009) 4:31–6.
85. Christian SG, Elekima I, Obisike UA, Aleru CP. Effect of petroleum on haematological parameters and lead level in fuel attendants in Port Harcourt, Nigeria. Int J Sci Res. (2016) 5:280–3. doi: 10.21275/v5i3.NOV161744
86. Emokpae MA, Oyakhire FO. Levels of some reproductive hormones, cadmium and lead among fuel pump attendants in Benin City, Nigeria. Afr J Med Health Sci. (2020) 19:70–7. doi: 10.5897/AJMHS2020.0106
87. Eze AN, Eluke BC, Eluke CC, Ezigbo E, Uzoma I. The effect of chronic occupational exposure to petroleum products on haematological and biochemical parameters of petrol attendants. J Adv Med Med Res. (2019) 28:1–8. doi: 10.9734/JAMMR/2018/31745
88. Obi E, Ifeanyichukwu MO, Ilo EC, Anyiam AF. Toxicological and Biochemical Profile of Gasoline Station Workers in Onitsha, Anambra State. Toxicol Digest. (2017) 1:92−100.
89. Onuegbu AJ, Olisekodiaka MJ, Nwaba EI, Adeyeye AD, Akinola FF. Assessment of some renal indices in people occupationally exposed to lead. Toxicol Ind Health. (2011) 27:475–9. doi: 10.1177/0748233710390020
90. World Bank. Data for Lower middle income, Nigeria (2023). Available online at: https://data.worldbank.org/?locations=XN-NG (accessed October 15, 2023).
91. FGN. Second Biennial Update Report (BUR2) to the United Nations Framework Convention on Climate Change. Abuja: Federal Ministry of Environment (2021).
92. Aba MM, Amado NB, Rodrigues AL, Sauer IL, Richardson A-AM. Energy transition pathways for the Nigerian Road Transport: Implication for energy carrier, Powertrain technology, and CO2 emission. Sustain Prod Consum. (2023) 38:55–68. doi: 10.1016/j.spc.2023.03.019
93. SRN. Solar in Nigeria. The Hague: Netherlands Enterprise Agency. Solar Report Nigeria (rvo.nl) (2021).
94. USEIA. Country Analysis Executive Summary: Nigeria. US Energy Information Administration (2020). Available online at: https://www.eia.gov/international/content/analysis/countries_long/Nigeria/NigeriaCAXS_2020.pdf (accessed October 9, 2022).
95. Ana G, Adeniji B, Ige O, Oluwole O, Olopade C. Exposure to emissions from firewood cooking stove and the pulmonary health of women in Olorunda community, Ibadan, Nigeria. Air Qual Atmos Health. (2013) 6:465–71. doi: 10.1007/s11869-012-0183-6
96. Oluwole O, Ana GR, Arinola GO, Wiskel T, Falusi AG, Huo D, et al. Effect of stove intervention on household air pollution and the respiratory health of women and children in rural Nigeria. Air Qual Atmos Health. (2013) 6:553–61. doi: 10.1007/s11869-013-0196-9
97. REN21. ECOWAS Renewable Energy and Energy Efficiency. Status Report. Paris: Renewable Energy Policy Network for the 21st Century (2014).
98. Onyekwena C, Ishaku J, Akanonu PC. Centre for the study of the economies of Africa. Electrification in Nigeria: Challenges and Way forward (Second Draft). CSEA-Electricity-Project-Nigeria-draft-report.pdf (cseaafrica.org) (2017).
99. Owebor K, Diemuodeke EO, Briggs TA, Imran M. Power Situation and renewable energy potentials in Nigeria e A case for integrated multi-generation technology. Renew Energy. (2021 177:773e796 doi: 10.1016/j.renene.2021.06.017
100. Fayiga AO, Ipinmoroti MO, Chirenje T. Environmental pollution in Africa. Environ Dev Sustain. (2018) 20:41–73. doi: 10.1007/s10668-016-9894-4
101. World Bank. Global Flaring Data. Global gas flaring reduction partnership (GGFP) (2022). Available online at: https://www.worldbank.org/en/programs/gasflaringreduction/global-flaring-data (accessed February 16, 2024).
102. Oluwagbemi A. IGP Orders Prosecution of Persons Selling Petrol in Plastic Containers. Lagos: PUNCH Media Foundation (2016).
103. Oyema-Aziken C. Federal Government Flags off Generator, Vehicular Emissions Control Programmes. Abuja: THE AUTHORITY NEWS (authorityngr.com) (2023).
104. Akinlo AE. Electricity consumption and economic growth in Nigeria: evidence from cointegration and co-feature analysis. J Policy Model. (2009) 31:681–93. doi: 10.1016/j.jpolmod.2009.03.004
105. Babayemi JO, Ogundiran MB, Osibanjo O. Overview of environmental hazards and health effects of pollution in developing countries: a case study of Nigeria. Environ Qual Manag. (2016) 26:51–71. doi: 10.1002/tqem.21480
106. Anyanwu BO, Ezejiofor AN, Igweze ZN, Orisakwe OE. Heavy metal mixture exposure and effects in developing nations: an update. Toxics. (2018) 6:65. doi: 10.3390/toxics6040065
107. Pona HT, Xiaoli D, Ayantobo OO, Tetteh ND. Environmental health situation in Nigeria: current status and future needs. Heliyon. (2021) 7:e06330. doi: 10.1016/j.heliyon.2021.e06330
108. State of Global Air(SGA) (2019). Soga_2019_nigeria.pdf (https://stateofglobalair.org).
109. UNDESA. World Population Prospects 2019, Volume II: Demographic Profiles. United Nations Department of Economic and Social Affairs Population Division (2019). Available online at: https://population.un.org/wpp/Publications/Files/WPP2019_Volume-II-Demographic-Profiles.pdf (accessed February 3, 2021).
110. Bruno P, Caselli M, De Gennaro G, Scolletta L, Trizio L, Tutino M. Assessment of the impact produced by the traffic source on VOC level in the urban area of Canosa di Puglia (Italy). Water Air Soil Pollut. (2008) 193:37–50. doi: 10.1007/s11270-008-9666-3
111. Thi T, Lan N, Minh PA. BTEX pollution caused by motorcycles in The Megacity of Ho Chi Minh, J. Environ Sci25. (2013) 348–56. doi: 10.1016/S1001-0742(12)60045-X
112. Odogun A, Georgakis P. Transport pollution: a research of the Nigerian transport sector. Int J Innovat Technol Exploring Eng. (2019) 8:492–7. doi: 10.35940/ijitee.K1083.09811S19
114. Omofonmwan SI, Osa-Edoh GI. The challenges of environmental problems in Nigeria. J Hum Ecol. (2008) 23:53–7. doi: 10.1080/09709274.2008.11906054
115. Oluwole V. Demand for Used Cars in Nigeria Surges amid High Inflation and Declining GDP (2023). Available online at: https://africa.businessinsider.com/local/markets/demand-for-used-cars-in-nigeria-surges-amid-high-inflation-and-declining-gdp/yhgtggv (accessed December 7, 2023).
117. Ayetor GK, Mbonigaba I, Sackey MN, Andoh PY. Vehicle regulations in Africa: Impact on used vehicle import and new vehicle sales. Transp Res InterdiscipPerspect. (2021) 10:100384. doi: 10.1016/j.trip.2021.100384
118. Ezeoha A, Okoyeuzu C, Onah E, Uche C. Second-hand vehicle markets in West Africa: a source of regional disintegration, trade informality and welfare losses. Bus Hist. (2019) 61:187–204. doi: 10.1080/00076791.2018.1459087
120. Dioha MO, Duan L, Ruggles TH, Bellocchi S, Caldeira K. Exploring the role of electric vehicles in Africa's energy transition: A Nigerian case study. IScience. (2022) 103926. doi: 10.1016/j.isci.2022.103926
121. Dioha MO, Kumar A. Exploring the energy system impacts of Nigeria's Nationally Determined Contributions and low-carbon transition to mid-century. Energy Policy. (2020) 144:111703. doi: 10.1016/j.enpol.2020.111703
122. Lo J. Nigeria Commits to Annual Carbon Budgets to Reach Net Zero under Climate Law (Climate Home News) (2021). Available online at: https://www.climatechangenews.com/2021/11/22/nigeria-commits-annual-carbon-budgets-reach-net-zero-climate-law/ (accessed November 22, 2021).
123. Conversation. Climate Change: 3 Key Goals Nigeria Must Focus on at COP28. London: The Conversation Trust (UK) Limited (theconversation.com) (2023).
124. Global Climate Action at COP28. (GCA28). Summary_GCA_COP28.pdf (unfccc.int). Global Climate Action at COP28 (2023).
125. NOA. Nigeria's wins at COP28 Summit in Dubai. National Orientation Agency(2023). Available online at: https://www.noa.gov.ng/nigerias-wins-at-cop28-sumit-in-dubai/ (accessed February 16, 2024).
126. Olaiya TT. COP28: Nigeria Reaps Windfall in Million-Dollar Africa-Focused Pledges. Lagos: The Guardian Nigeria News - Nigeria and World News — Nigeria (2023).
127. Grzegorz P, Midgledimitri Z, John W. Diversification and Cooperation in a Decarbonizing World: Climate Strategies for Fossil-Fuel Dependent Countries. Development and a Changing Climate (2020). Available online at: https://blogs.worldbank.org/climatechange/diversification-and-cooperation-decarbonizing-world-climate-strategies-fossil-fuel (accessed July 2, 2020).
128. Evans O, Nwaogwugwu I, Vincent O, Wale-Awe O, Mesagan E, Ojapinwa T. The socio-economics of the 2023 fuel subsidy removal in Nigeria. BizEcons Q. (2023) 17:12–32.
129. Afolabi OT, Olajide FO, Omotayo SK. Assessment of safety practices in filling stations in Ile-Ife; South-Western Nigeria. JCMPHC. (2011) 23:9–15.
130. Akodu AK, Okafor UAC, Adebayo AV. Prevalence of Low Back Pain among Filling Stations Attendants in Lagos, Southwest Nigeria. Afr J Biomed Res. (2016) 19:109–15.
131. Kakwi JD. Compliance With Occupational Safety Practice Among Petrol Station Pump Attendants in Kaduna State, Nigeria (Bsc thesis). Kenyatta University, Nairobi, Kenya (2016).
132. Chijoke S. Effect of occupational hazards and safety practices among petrol attendants in Nigeria. Eur J Public Health. (2020) 30:2020–2001. doi: 10.1093/eurpub/ckaa166.1354
133. Emeka AH, Achalu EI. Influence of demographic variables on fire safety hazards exposure and adherence to control measures among workers of petrol filling stations in Port Harcourt Metropolis, Nigeria. Eur J Public Health. (2021) 4:1–11. doi: 10.46827/ejphs.v4i2.93
134. Lawal AH. Environmental Risk Factor Identification and Assessment of Health Outcomes on Selected Subjects in and Around the Vicinity of Petrol Stations in Ilorin, Kwara state, Nigeria (Dissertation). Cardiff Metropolitan University, Cardiff, United Kingdom (2022).
135. Kassy WC, Ochie CN, Aniebue CA, Ndu AC, Arinze-Onyia SU, Aguwa EN, et al. Risk Perception amongst Petrol Pump Attendants and Analysis of Indiscriminate Siting of Petrol Stations in Enugu Metropolis. West Afr J Med. (2023) 40:181–9.
136. Onunkwor B, Dosumu O, Odukoya OO, Arowolo T, Ademuyiwa O. Biomarkers of lead exposure in petrol station attendants and auto-mechanics in Abeokuta, Nigeria: effect of 2-week ascorbic acid supplementation. Environ Toxicol Pharmacol. (2004) 17:169–76. doi: 10.1016/j.etap.2004.04.003
137. Sofola OA, Akintonwa A, Emeka P, Ladipo C, Raji I. Peak expiratory flow rate in petroleum depot workers and petrol filling stations attendants. Niger Med Pract. (2005) 43:22–5. doi: 10.4314/nmp.v47i3.28745
138. Ademuyiwa O, Ugbaja RN, Idumebor F, Adebawo O. Plasma lipid profiles and risk of cardiovascular disease in occupational lead exposure in Abeokuta, Nigeria. Lipids Health Dis. (2005) 4:1–7. doi: 10.1186/1476-511X-4-19
139. Ademuyiwa O, Ugbaja RN, Ojo DA, Owoigbe AO, Adeokun SE. Reversal of aminolevulinic acid dehydratase (ALAD) inhibition and reduction of erythrocyte protoporphyrin levels by Vitamin C in occupational lead exposure in Abeokuta, Nigeria. Environ Toxicol Pharmacol. (2005) 20:404–11. doi: 10.1016/j.etap.2005.04.002
140. Akintomiwa A, Ojo BA, Emeka P, Coker AB, Sofola O. Effect of chronic exposure to petroleum products on some hematological and biochemical parameters. Nigerian Q J Hosp Med. (2005) 15:77–82. doi: 10.4314/nqjhm.v15i2.12761
141. Akinosun OM, Arinola OG, Salimonu LS. Immunoglobulin classes and liver function immunoglobulin classes and liver function tests in Nigerian petrol attendants. Indian J Occup. (2006) 10:58–61. doi: 10.4103/0019-5278.27300
142. Okoro AM, Ani EJ, Ibu JO, Akpogomeh BA. Effect of petroleum products inhalation on some haematological indices of fuel attendants in Calaber Metropolis, Nigeria. Niger J Physiol Sci. (2006) 21:71–5. doi: 10.4314/njps.v21i1-2.53954
143. Ademuyiwa O, Ugbaja RN, Rotimi SO, Abama E, Okediran BS, Dosumu OA, et al. Erythrocyte acetylcholinesterase activity as a surrogate indicator of lead-induced neurotoxicity in occupational lead exposure in Abeokuta, Nigeria. Environ Toxicol Pharmacol. (2007) 24:183–8. doi: 10.1016/j.etap.2007.05.002
144. Nwanjo HU, Ojiako OA. Investigation of the potential health hazards of petrol station attendants in Owerri, Nigeria. J Appl Sci Environ. (2007) 11:197–200. doi: 10.4314/jasem.v11i2.55040
145. Abama E, Okedirana BS, Odukoya OO, Adamsona I, Ademuyiwaa O. Reversal of ionoregulatory disruptions in occupational lead exposure by vitamin C. Environ Toxicol Pharmacol. (2008) 26:297–304. doi: 10.1016/j.etap.2008.05.008
146. Udonwa N, Udo EK, Ikpeme BM, Ibanga IA, Okon BO. Exposure of petrol station attendants and auto mechanics to premium motor spirit fumes in Calabar, Nigeria. J Environ Public Health. (2009) 281876. doi: 10.1155/2009/281876
147. Gali R, Daja A, Mamza Y, Ani G, Ani G. Liver enzymes and protein among petrol hawkers and petrol-pump attendants in a Nigerian population. Adv Lab Med Int. (2012) 2:123–9.
148. Festus OO, Dada FL, Iweka FK, Eyaufe AO, Osagie RN, Osagie EV, et al. Plasma renal functions amongst petrol station Attendants in Owerri, Southeast, Nigeria. Int J Community Res. (2013) 2:34–8.
149. Ogodo AC, Ekeleme UG. Comparative study on the nasal bacterial colonization of petrol station staff and non-petrol station staff. Aust J Basic Appl Sci. (2013) 7:264–8.
150. Ogunneye AL, Omoboyowa A, Sonibare L, Adebusuyi J, Faniran P. Hepatotoxic and Nephrotoxic Effects of Petroleum Fumes on Petrol Attendants in Ibadan, Nigeria. Niger J Basic Appl Sci. (2014) 22:57–62. doi: 10.4314/njbas.v22i3.1
151. Adeniyi BO. Pulmonary function and symptoms among petrol pump workers in Nigeria. Int J Biol Med Res. (2014) 5:3780–4.
152. Odewabi AO, Ogundahunsi OA, Oyalowo M. Effect of exposure to petroleum fumes on plasma antioxidant defense system in petrol attendants. Br J Pharmacol Toxicol. (2014) 5:83–7. doi: 10.19026/bjpt.5.5461
153. Ajugwo AO, Adias TC, Aghatise K, Fadairo JK, Nyenke CU. Reduced haematological indices in auto-mechanics and fuel attendants in Elele Nigeria. Am J Med Biol Res. (2014) 2:1–4. doi: 10.12691/ajmbr-2-1-1
154. Isirima JC, Angalabiri-Owei BE. Haematologic and biochemical implications of inhalation of fumes of petroleum products. Afr J Cell Pathol. (2014) 2:40–7. doi: 10.5897/AJCPATH14.006
155. Ogunkoya JO. Lung Function Tests In petrol Station Attendants in Sagamu, Southwest Nigeria (Dissertation). National Post-graduate Medical College of Nigeria, Lagos, Nigeria (2015). Available online at: https://dissertation.npmcn.edu.ng/index.php/FMCP/article/view/599/602 (accessed August 26, 2022).
156. Alli LA. Blood level of cadmium and lead in occupationally exposed persons in Gwagwalada, Abuja, Nigeria. Interdiscipl Toxicol. (2015) 8:146–50. doi: 10.1515/intox-2015-0022
157. Emeji R, Ifeanyi OE, Roseline I, Barasua E. Electrolyte concentration in fuel pump attendants within port-harcourt metropolis. European J Pharm Med Res. (2015) 2:110–4.
158. Uko EK, Erhabor O, Bashiru GA, Isaac I, Abdulrahaman Y, Aghedo F, et al. Some hematological indices among petrol station attendants occupationally exposed to premium motor spirit in Sokoto, North Western, Nigeria. J Int Res Med Pharm Sci. (2015) 4:53–8.
159. Opute P, Oghortaire BC, Osazee EN, Tawari-Fufeyin P. Comparative Haematology and Urinary Analysis of Passive Inhalers of Petrol Fumes (Petrol Station Attendants) in Benin City, Nigeria. Euro Int J Sci Technol. (2015) 4:1–9.
160. Kalio IS, George DMC, Eddeh-Adjugah OG. Evaluation of total protein, albumin and globulin concentrations in fuel pump attendants in Port Harcourt metropolis, Nigeria. World J Pharm Res. (2015) 4:169–76.
161. Adamu S, Akinosun O, Abbiyesuku F, Kuti M, Jibril M. Are roadside petrol dispensers at risk of renal dysfunction? A study from Gombe, northeast Nigeria. Borno Med. (2015) 12:16–22.
162. Ibeh N, Aneke J, Okocha C, Okeke C, Nwachukwuma J. The influence of occupational lead exposure on haematological indices among petrol station attendants and automobile mechanics in Nnewi, South-East Nigeria. J Environ Occup Sci. (2016) 5:1–6. doi: 10.5455/jeos.20160320022500
163. Ifeyinwa AE, Emerole CO, Amadi AN, Nnodim J. Gasoline fumes exposure and risk of respiratory disease among fuel pump attendants in Owerri Municipal Council, Nigeria. J Adv Biol Basic Res. (2016) 2:9–17.
164. Umegbolu E, Ogamba JO, Unkekwe PC. Detection of micronuclei formation in petrol station pump attendants in Awka, Awka South, Anambra state, Nigeria. Inter J ToxicolPharmRes. (2016) 8:53–8.
165. Ciroma FL, Yusuf MS, Omole VN, Dikko HA, Abubakar AA, Akor-Dewu MB. Bioethical implications of the effects of benzene exposure in respiratory functions of petroleum pump workers in Kaduna Metropolis, Nigeria. Global Bioethics Enq. (2016) 4:25–9.
166. Kalio IS, Hanson AH. Evaluation of anion gap in petrol pump attendants in Port Harcourt metropolis, Nigeria. World J Pharm Res. (2016) 5:1499–506.
167. Iyanda AA, Anetor JI. Biomarkers of hepato-renal damage of fuel filling station attendants using or abstaining from use of protective gears. Ann Clin Chem Lab Med. (2017) 3:15–21. doi: 10.3126/acclm.v3i1.17176
168. Anakwue AM, Anakwue R, Okeji M, Idigo F, Agwu K, Nwogu U. Sonographic assessment of petroleum-induced hepatotoxicity in Nigerians: does biochemical assessment underestimate liver damage? Afri Health Sci. (2017) 17:270–7. doi: 10.4314/ahs.v17i1.33
169. Christian SG, Eze EM. Effect of exposure to petroleum products on methehaemoglobin levels of fuel station attendants in Port Harcourt, Nigeria. Sokoto J Med Lab Sci. (2017) 2:69–74.
170. Iyanda AA. Serum heavy metal levels in teenagers currently or formerly employed as gas station attendants. Bangladesh J Medical Sci. (2018) 17:224–9. doi: 10.3329/bjms.v17i2.35875
171. Dissi GM. Assessment of cardiopulmonary function and respiratory symptoms among petrol pump attendants in Kano Metropolis. Dutse J Pure Appl Sci. (2018) 4:374–82.
172. Airhomwanbor OK, Dic-Ijiewere OE, Idehen IC, Eidangbe AP, Ehimare RI, Uwuigbe M, et al. Assessment of some heavy metals among petrol station attendants in Ekpoma and its environs. Adv Biomed Sci. (2018) 3:8–12.
173. Obeagu EI, Obeagu GU, Ekelozie IS, Ochei KC, Swem CA. Comparative study of trace elements level in petroleum attendants exposed to petroleum pollutant in Umuahia. Int J Curr Res Biol Med. (2018) 3:26–31. doi: 10.22192/ijcrbm.2018.03.02.005
174. Ben-Chioma AE, Nwachuku EO. Assessment of cadmium, lead and mercury levels on petrol attendants and welders in obio-akpor and phalga in Rivers State. Int J Contemp Med Res. (2018) 5:1–5. doi: 10.21276/ijcmr.2018.5.11.16
175. Adamu S, Akinosun OM, Abbiyesuku FM, Kuti MAO, El-Bashir JM, Abubakar JD. Are roadside petrol dispensers at risk of oxidative stress? A study from Gombe, North East Nigeria. Niger J Clin Pract. (2018) 21:276–9. doi: 10.4103/njcp.njcp_186_17
176. Ovuakporaye SI. Assessment of changes in cardiovascular parameters among petrol pump attendants in Ughelli, Delta State Nigeria. J Appl Sci Environ Manage. (2019) 23:2071–5. doi: 10.4314/jasem.v23i11.26
177. Anakwue A-MC, Idigo FU, Anakwue RC. Renal echotextural changes in Nigerian workers chronically exposed to petroleum-based liquid fuels. J Ultrason. (2020) 20:18–23. doi: 10.15557/JoU.2020.0004
178. Okemuo AJ, Ominyi LA, Ojukwu CP, Uchenwoke CI, Chukwu CS, Ezugwu UA. Assessment of respiratory symptoms and cardiopulmonary indices among petrol pump attendants in Enugu Metropolis. Int J Med Health Dev. (2020) 25:106–11. doi: 10.4103/ijmh.IJMH_9_20
179. Anyiam AF, Obi E, Ifeanyichukwu MO, Ilo EC. Effects of gasoline on haematological parameters of gasoline station workers in Onitsha, Anambra State, Nigeria. Sokoto J Med Lab Sci. (2020) 5:5–10.
180. Okeke CO, Kelechi M. Comparison of Blood Carboxyhaemoglobin levels among cigarette smokers and petrol station attendants with control subjects in Nnewi Metropolis, Nigeria. J Med Lab Sci. (2020) 30:85–93. doi: 10.5281/zenodo.4039516
181. Ufelle S, Onyekwelu K, Chinweoke A, Ibegbu D, Okoli U, Ikekpeazu J. Assessment of hepatic functions, hematopoietic cytokines and haematological parameters in people occupationally exposed to volatile petroleum hydrocarbons. Arch Environ Occup Health. (2021) 76:567–71, doi: 10.1080/19338244.2020.1832037
182. Onitsha EN, Eguro ET, Okutu JB, Okonkwo BN. Evaluation of the effect of gasoline on serum calcium, magnesium, and phosphorus level in petrol station attendants in Yenagoa, Nigeria. World J Pharm Res. (2021) 10:28–37. doi: 10.20959/wjpr20214-20055
183. Obeagu EI, Owojori IO, Hassan AO. Evaluation of haematogical parameters of petroleum attendants based on sex in Ondo. J Clin Lab Res. (2021) 4:1–3. doi: 10.31579/2768-0487/059
184. Okeke C, Onyekaomelu A, Umeh O, Ibeh N, Chukwuma O. Impact of occupational exposure to petroleum products on coagulation and white blood cell indices of Petrol station attendants in Nnewi metropolis, Nigeria. J Curr Biomed Res. (2022) 2:359–71. doi: 10.54117/jcbr.v2i4.11
185. Eworo RE, Fabian UA, Luke UO, Usoro CA, Thomas C, Johnson DD, et al. Enhancement of oxidative stress, oxidative DNA damage and lowered PEFR in gasoline station attendants in Calabar Metropolis. Global J Pure Appl Sci. (2023) 29:63–71. doi: 10.4314/gjpas.v29i1.8
186. Okonkwo U, Orji I, Onwuamaeze I. Environmental impact assessment of petrol and gas filling stations on air quality in Umuahia Nigeria. Global J Eng Res. (2014) 13:11–20. doi: 10.4314/gjer.v13i1.2
187. Adebiyi FM, Ezehb GC, Adeyemi FA, Obioh IB. Trace elements in particulate matter of ambient air at petroleum filling stations. Toxicol Environ Chem. (2015) 97:847–56. doi: 10.1080/02772248.2015.1071377
188. Lawal AO, Salisu AG, Saidu A, Isah HH, Habila SK. Assessment of vehicular emission and volatile organic contaminants in the central state of North Central Nigeria. Ame J Environ Eng. (2018) 8:54–73.
189. Olabisi OL. Air Quality Assessment and Associated Health and Safety Measures in Selected Filling Stations in Ilorin Metropolis (Dissertation). Kwara State University, Ilorin, Kwara State, Nigeria (2019).
190. Oni TM, Ana GREE. Ambient air pollution exposure and lung function assessment of filling station attendants in Ibadan, Nigeria. Rev Environ Health. (2019) 34:211–8. doi: 10.1515/reveh-2018-0027
191. Ana GR, Oni TM, Shendell DG. Carbon monoxide and reported health conditions among filling station attendants in Ibadan. J Environ Health. (2020) 83:26–31.
192. Odilichukwu AA, Farouq AU, Idahosa VA, Augustine OC. Comparative study of workers exposure to volatile compounds in cooking gas and petrol stations in Effurun and Environs. Asian J Environ Ecol. (2022) 19:21–9. doi: 10.9734/ajee/2022/v19i4416
193. FEPA. Guidelines and standards for environmental protection and control. FEPA Publ. (1996) 1:32–3.
194. Lewne M, Nise G, Lind ML, Gustavsson P. Exposure to particles and nitrogen dioxide among taxi, bus, and lorry drivers. Int Arch Occup Environ Health. (2006) 79:220–6. doi: 10.1007/s00420-005-0047-6
195. Pranjic N, Mujagic H, Nurkic M, Karamehic J, Pavlonic S. Assessment of health effects in workers at gasoline station. Bosn J Basic Med Sci. (2002) 2:35–45. doi: 10.17305/bjbms.2002.3579
196. DPR. DPR Guidelines for Approval to Construct and Operate Petroleum Products Filling Station. Department of Petroleum Resources (2022). Available online at: https://www.nmdpra.gov.ng/wp-content/uploads/2021/12/FILLING-STATION-GUIDELINES.pdf (accessed January 16, 2022).
197. Alyami AR. Assessment of Occupational Exposure to Gasoline Vapour at Petrol Stations (Dissertation). Cranefield University, Cranfield (2016).
198. Moolla R, Curtis CJ, Knight J. BTEX concentrations influenced by external factors at a diesel-refuelling station in Johannesburg, South Africa. WIT Trans Ecol Environ. (2014) 191:1459–67. doi: 10.2495/SC141232
199. Periago JF, Zambudio A, Prado C. Evaluation of environmental levels of aromatic hydrocarbons in gasoline service stations by gas chromatography. J Chromatogr A. (1997) 778:263–8. doi: 10.1016/S0021-9673(97)00390-7
200. WHO. Exposure to Lead; a Major Public Health Concern, Second Edition. Preventing Diseases Through Health Environments. Structure of Mercury Paper (who.int). Geneva: World Health Organization (2021).
201. Landrigan PJ. The worldwide problem of lead in petrol. Bulletin of the World Health 1219–1225. Organization. (2002) 80:768–9.
202. Chaiklieng S. Risk assessment of workers' exposure to BTEX and hazardous area classification at gasoline stations. PLoS ONE. (2021) 16:e0249913. doi: 10.1371/journal.pone.0249913
203. WHO. Inorganic Lead. Geneva, World Health Organization, International Programme on Chemical Safety; Environmental Health Criteria 165 (1995). Available online at: http://www.inchem.org/documents/ehc/ehc/ehc165.htm (accessed February 16, 2024).
204. USEPA. Integrated Science Assessment for Lead. Washington, DC: United States Environmental Protection Agency (2013). available online at: https://cfpub.epa.gov/si/si_public_record_report.cfm?Lab=NCEA&dirEntryId=255721 (accessed October 20, 2020).
205. Giao NT, Anh PK, Nhien HTH. Health risk assessment for the exposure of workers to BTEX at the gasoline stations. J Appl Sci Environ Manage. (2021) 25:71–7. doi: 10.4314/jasem.v25i1.10
206. IARC. Summaries & Evaluations: Inorganic and Organic lead Compounds. IARC Monographs for the Evaluation of Carcinogenic Risks to Humans. Vol. 87. Lyon: International Agency for Research on Cancer (2006). Available online at: https://inchem.org/documents/iarc/vol87/volume87.pdf (accessed February 16, 2024).
207. Rezazadeh AM, Naghavik Z, Zayeri F, Salehpour S, Seyedi MD. Occupational exposure of petroleum depot workers to BTEX compounds. Int J Occup Environ Med. (2012) 3:39–44.
208. Yin Y, Tan X, Fan J. Occupational fatigue and health of gas station workers: a review. Work. (2023) 76:707–26. doi: 10.3233/WOR-220415
209. Emudainohwo E. Analyzing the duties of employer and employee in the Nigerian Law. Beijing Law Rev. (2021) 12:305–19. doi: 10.4236/blr.2021.122018
210. Petroleum Industry Act, NO 6, 2021 (PIA). Midstream and Downstream Petroleum Safety Regulations. Lagos (2021). Available online at: https://www.nmdpra.gov.ng/wp-content/uploads/2023/07/Midstream-and-Downstream-Petroleum-Safety-Regulations-2023.pdf (accessed June 23, 2023).
211. Edem M, Nwankwo O, Muku J, Usman F, Ike C. Reducing accidents through the implementation of the minimum industry safety training for downstream operations mistdo in the Nigerian Oil and Gas Industry. In: Paper presented at the SPE Nigeria Annual International Conference and Exhibition, Lagos, Nigeria, August 2021. Paper Number: SPE-207085-MS (2021).
212. Blamah NV, Vivan EL, Tagwi MU, Ezemokwe IU. Service stations locational impact assessment of gasoline along Abuja Keffi Road and Environs in Karu, Abuja, Nigeria. J Environ Manag Saf. (2012) 3:106–23.
213. Njoku C, Alagbe A. Site suitability assessment of petrol flling stations (PFSs) in Oyo Town, Oyo State, Nigeria: a geographic information systems (GIS) approach. IOSR J Environ Sci Toxicol Food Technol. (2015) 9:8–19.
214. Ezenwa AO. A study of fatal injuries in Nigerian factories. Occup Med. (2001) 51:485–9. doi: 10.1093/occmed/51.8.485
215. Diugwu IA, Baba DL, Egila AE. Effective regulation and level of awareness: an expose of the nigeria's construction industry. Open J Saf Sci Technol. (2012) 2:140–6. doi: 10.4236/ojsst.2012.24018
216. Kalejaiye P. Occupational health and safety: issues, challenges and compensation in Nigeria. Peak J Public Health Manag. (2013) 1–2, 16−23.
217. Idubor EE, Oisamoje MD. An exploration of health and safety management issues in Nigeria's efforts to industrialize. Eur Sci J. (2013) 9:154–69.
218. Baghani AN, Sorooshian A, Heydari M. case study of BTEX characteristics and health effects by major point sources of pollution during winter in Iran. Environ Pollut. (2019) 247:607–17. doi: 10.1016/j.envpol.2019.01.070
219. Ekpenyong CE, Asuquo AE. Recent advances in occupational and environmental health hazards of workers exposed to gasoline compounds. Int J Occup Med Environ Health. (2017) 30:1–26. doi: 10.13075/ijomeh.1896.00800
220. Xiong F, Li Q, Zhou B, Huang J, Liang G, Zhang L, et al. Oxidative stress and genotoxicity of long-term occupational exposure to low levels of BTEX in gas station workers. Int J Environ Res Public Health. (2016) 13:1212. doi: 10.3390/ijerph13121212
221. Tongsantia U, Chaiklieng S, Suggaravetsiri P, Andajani S, Autrup H. Factors affecting adverse health effects of gasoline station workers. Int J Environ Res Public Health. (2021) 18:10014. doi: 10.3390/ijerph181910014
222. Esmaelnejad F, Hajizadeh Y, Pourzamani H, Amin M. Monitoring of benzene, toluene, ethyl benzene, and xylene isomers emission from Shahreza gas stations in 2013. In J Environ Health Eng. (2015) 1:1–7.
223. Karakitsiosa SP, Papaloukasb CL, Kassomenosc PA, Pilidis GA. Assessment and prediction of exposure to benzene of filling station employees. Atmospheric Environ. (2007) 41:9555–69. doi: 10.1016/j.atmosenv.2007.08.030
224. Allahabady A, Yousefi Z, Mohammadpour TRA, Payandeh SZ. Measurement of BTEX (benzene, toluene, ethylbenzene and xylene) concentration at gas stations. Environ Health Eng Manag. (2022) 9: 23–31. doi: 10.34172/EHEM.2022.04
225. Keretetse GS, Laubscher PJ, Du Plessis JL, Pretorius PJ, Van Der Westhuizen FH, Van Deventer E, et al. DNA Damage and repair detected by the comet assay in lymphocytes of african petrol attendants: a pilot study. Ann Occup Hyg. (2008) 52:653–62. doi: 10.1093/annhyg/men047
226. Periago JF, Prado C. Evolution of occupational exposure to environmental levels of aromatic hydrocarbons in service stations. Ann Occup Hygiene. (2005) 49:233–40.
227. Huy LN, Oanh NTK. Emission control for volatile organic compounds from gasoline stations and implication on ozone-forming potential. Atmospheric Pollut Res. (2020) 11:87–98. doi: 10.1016/j.apr.2020.03.002
228. Page NP, Mehlman M. Health effects of gasoline refueling vapors and measured exposures at service stations. Toxicol Ind Health. (1989) 5:869–90. doi: 10.1177/074823378900500521
229. Directive 2008/50/EC. European Parliament and Council Directive of 21 May 2008 on Ambient Air Quality and Cleaner Air for Europe (2008). Available online at: https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32008L0050&from=en (accessed January 19, 2019).
230. NER. National Environmental Regulations (2021). Available online at: https://gazettes.africa/archive/ng/2021/ng-government-gazette-supplement-dated-2021-02-17-no-161.pdf (accessed July 23, 2023).
231. Zaheer AN, Luiza CC, Nicola C, Ian C. Airborne biological hazards and urban transport infrastructure: current challenges and future directions. Environ Sci Pollut Res. (2016) 23:15757–66. doi: 10.1007/s11356-016-7064-8
232. USEPA Chapter 5: Petroleum Industry (2008). Available online at: https://www3.epa.gov/ttnchie1/ap42/ ch05/ I fifth ed (accessed February 3, 2020).
233. WHO. Air Quality and Health. Sustainable Development Goals and Air Pollution. World Health Organization (2023). Available online at: https://www.who.int/teams/environment-climate-change-and-health/air-quality-energy-and-health/policy-progress/sustainable-development-goals-air-pollution (accessed February 16, 2024).
234. WHO. The Global Health Observatory. World Health Organization (2023). Available online at: https://www.who.int/data/gho/data/themes/sustainable-development-goals (accessed July 30, 2023).
Keywords: narrative review, BTEX exposure, cancer and non-cancer risks, petrol stations, Sustainable Development Goals, Nigeria
Citation: Anigilaje EA, Nasir ZA and Walton C (2024) Exposure to benzene, toluene, ethylbenzene, and xylene (BTEX) at Nigeria's petrol stations: a review of current status, challenges and future directions. Front. Public Health 12:1295758. doi: 10.3389/fpubh.2024.1295758
Received: 17 September 2023; Accepted: 02 February 2024;
Published: 25 March 2024.
Edited by:
Silvia Fustinoni, University of Milan, ItalyReviewed by:
Boris Johnson-Restrepo, University of Cartagena, ColombiaEmina Kristina Petrovic, Victoria University of Wellington, New Zealand
Copyright © 2024 Anigilaje, Nasir and Walton. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Emmanuel Ademola Anigilaje, demolaanigilaje2@gmail.com; emmanuel.anigilaje@cranfield.ac.uk; Christopher Walton, c.walton@cranfield.ac.uk
‡ORCID: Emmanuel Ademola Anigilaje orcid.org/0000-0002-1260-5387
Zaheer Ahmad Nasir orcid.org/0000-0002-9953-7144
Christopher Walton orcid.org/0000-0001-8443-1139
†These authors share first authorship