Arsenic, lead, and uranium, naturally occurring contaminants in some groundwater, are not uncommon in New England, where significant portions of the population rely on wells for drinking water. Long-term or acute exposure to these contaminants can lead to multiple types of cancer, heart disease, diabetes, and more. Federal and state guidelines regulate the maximum contaminant level (MCL) of many metals individually (10 ppb for arsenic, 15 ppb for lead, and 30 ppb for uranium), but little is known about the health effects of metal mixtures, particularly when individual metals are at levels considered safe for human consumption (at or below the MCL).
Remy Babich, doctoral candidate at the University of Maine, used drinking water samples collected by students involved in MDI Biological Laboratory’s SEPA project, All About Arsenic, to evaluate the effects of chemical mixtures on zebrafish behavior. As laid out in her paper, Defining drinking water metal contaminant mixture risk by coupling zebrafish behavioral analysis with citizen science, published on August 27, 2021 in Scientific Reports, an analysis of 4,016 mixture combinations revealed that certain metal mixtures affect zebrafish behavior more significantly, and that changes in zebrafish behavior are highly dependent on the mixture type. Babich’s data support the need to further study chemical mixtures in drinking water, even when all the contaminants are reportedly below the MCL, and assess their effects on human health. Her research has also demonstrated the efficacy of engaging citizen scientists in research and the resulting expansion of knowledge among participants in improving their own water quality.
Babich’s advisor is Nishad Jayasundara, Ph.D., Assistant Professor of Environmental Toxicology and Health at Duke University. Jayasundara is an alum of MDIBL’s summer fellowship program for undergraduates and joined our visiting scientist faculty in 2021. His lab studies adverse ecological and human health outcomes of anthropogenic environmental change. His research focuses on environmental health and comparative physiology; broadly examining how organisms modify a common set of biochemical processes to survive and adapt to their natural environment and working to understand organismal responses to rapidly changing global chemical and physical environments.
Student citizen scientists participating in the All About Arsenic project have collected almost 2,500 samples from wells in Maine and New Hampshire since 2018. The overall goal of the project, led by Jane Disney, Ph.D., MDI Biological Laboratory, and Bruce Stanton, Ph.D, Dartmouth College, is to provide teachers and students with the tools, skills and support to make sense of well water data so that their analyses can inform actions at the community level, resulting in positive public health outcomes.