Pharmaceutically Active Micropollutants – How Serious is the Problem and is there a Microbial Way Out?

Pharmaceutically active compounds (PhACs) include substances that are widely used in agriculture, medicine and biotechnology, such as antibiotics, drugs and hormones. Human and veterinary applications are the main sources of PhACs in the environment and the major pathways are excretion and discharge to the environment through sewage treatment plants (STPs). It is estimated that worldwide consumption of active compounds amounts to some 100,000 tons or more per annum. Some of these PhACs are extensively used as non-prescription drugs and after the intake; they are excreted with urine and feces either as active substances or metabolites. Antibiotic consumption has increased globally by more than 30% in past two decades, almost half of which is the result of improper use, leading to large amounts getting discharged into the environment. The occurrence of pharmaceutically active compounds (PhACs) in the environment have lately been acknowledged to constitute a health risk for humans and terrestrial and aquatic ecosystems.

PhACs have been detected ubiquitously in water environments and water distribution systems because of their high persistence and low adsorption properties. Photodegradation and biodegradation have been identified as the two major sinks for PhACs. Conventional treatment of domestic sewage provides very low – if any – reduction of antibiotics, which usually pass treatments and accumulate in water sediments. It has been a matter of concern that these sewage treatment plants or WWTPs are inefficient at removing some of these pollutants. However, the removal of PhACs in water and wastewater treatment is essential to prevent environmental contamination and its possible adverse effects. Therefore, it becomes imperative to develop efficient techniques for achieving their complete removal. Microorganisms from different eco-physiological niches have been reported to degrade and thus detoxify various chemicals such as azo dyes, petroleum hydrocarbons and a variety of pharmaceutical substances like paracetamol, anti-inflammatory drug Ibuprofen and antibiotics. A large number of studies related with reduction and removal of PhACs have come up, but few control policy studies could be formulated due to consolidation of results, and studies from wide geographical regions. In view of this, a special compilation of latest findings in this aspect is the need of time.

In this Research Topic, we intend to put forth the latest findings and developments on the following studies. However, the scope is not strictly limited to these:

• Studies focusing on water-soluble organic micropollutants in the effluents of wastewater treatment plants (WWTPs)
• Studies of analytical or systematic nature on global antibiotic consumption, improper use, its discharge into the environment
• Studies on the analysis of other generic or over the counter drugs, like paracetamol, analgesics, anti-inflammatory drugs, medicine to control blood sugar level etc., with high consumption and their subsequent widespread occurrence in WWTPs;
• Studies investigating isolation and screening of microbial strains for biodegradation of selected PhACs;
• Studies focused on bioremediation techniques and development of similar promising clean technology;
• Novel methods to investigate the prevalence and quantification of pharmaceutical compounds;
• Emerging studies to develop efficient techniques for achieving complete removal of PhACs from WWTPs;
• Studies on conceptualization of up-scaling of the procedure;
• Studies providing an insight on formulation of action plans, norms for usage, ways for monitoring, framework for regulatory guidelines and policies are also welcome.

We welcome submissions of Original Research articles, Reviews, Mini Reviews, Methods, Hypotheses and Theory articles to this Research Topic. In addition, Opinions and Perspectives on recommendations and policies in different countries and regions are also welcome.