Environmental Engineers Addressing the Grand Challenges of the 21st Century

W are happy to introduce our third issue of ACS Environmental Au in 2022. With this collection of eight research articles and critical reviews, we are proud to highlight the work of environmental engineers and scientists across the globe, addressing some of the most pressing challenges facing society. “The discipline of environmental engineering has no single, widely agreed-upon definition”here we quote the 2019 report from an ad hoc committee of the Water Science and Technology Board of the National Academies of Sciences, Engineering, and Medicine. In that inspiring report, in lieu of defining “environmental engineering” or identifying specific environmental challenges, the committee chose to identify “the most pressing challenges of the 21st century for which the expertise of environmental engineering will be needed to help resolve or manage’’. These grand challenges include (a) providing a sustainable supply of food, water and energy, (b) reducing climate change and adapting to its impacts, (c) designing a future without pollution and waste, (d) creating efficient, healthy, resilient cities, and (e) fostering informed decisions and actions. The COVID-19 pandemic has provided an additional challenge, and environmental engineers have stepped up to provide new technologies to help curb the pandemic. The contributions in this issue address many of these grand challenges of the 21 century. Below you will find a synopsis of the articles and review in this issue, grouped by the above-mentioned challenges that they are helping address.