AUTHOR=Duarte Armando C. TITLE=Specialty Grand Challenges in Environmental Analytical Methods JOURNAL=Frontiers in Environmental Chemistry VOLUME=1 YEAR=2020 URL=https://www.frontiersin.org/journals/environmental-chemistry/articles/10.3389/fenvc.2020.00004 DOI=10.3389/fenvc.2020.00004 ISSN=2673-4486