Municipal drinking water, regulated by the Environmental Protection Agency via the Safe Drinking Water act, has long been assumed to be contaminant-free. However, crises related to drinking water have emerged, most notably the “Flint Water Crisis” in Flint, MI, where high levels of lead (Pb) were detected in the area’s water. Much of the water-sampling data collected in Flint was obtained by “Citizen Scientists” working closely with a team of researchers at Virginia Tech, who used the analytical technique of Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to quantify metal ions present in the water. Inspired by these efforts, we developed adaptable public water testing outreach efforts, led by students in Baltimore city (Middle School, High School, and College), to test the city’s drinking water. These “student-scientists” read news and scientific articles to understand the public health impact of lead in drinking water and the analytical approaches scientists use to detect metal ions in water. The students then developed a written “water collection protocol” and sought participation from colleagues (other students, faculty, and staff) who collected their home drinking water to be tested. The student scientists prepared and analyzed samples for lead (Pb) as well as copper (Cu), iron (Fe), and zinc (Zn) metal ions commonly found in drinking water, to be tested via ICP-MS. Data were then plotted onto a map of Baltimore City, with the metal levels indicated for each Zip code. This outreach event connects science to real-life news events while teaching analytical methodology and can be tailored to students at various stages of their education.
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Defining drinking water metal contaminant mixture risk by coupling zebrafish behavioral analysis with citizen science
Contaminated drinking water is an important public health consideration in New England where well water is often found to contain arsenic and other metals such as cadmium, lead, and uranium. Chronic or high level exposure to these metals have been associated with multiple acute and chronic diseases, including cancers and impaired neurological development. While individual metal levels are often regulated, adverse health effects of metal mixtures, especially at concentrations considered safe for human consumption remain unclear. Here, we utilized a multivariate analysis that examined behavioral outcomes in the zebrafish model as a function of multiple metal chemical constituents of 92 drinking well water samples, collected in Maine and New Hampshire. To collect these samples, a citizen science approach was used, that engaged local teachers, students, and scientific partners. Our analysis of 4016 metal-mixture combinations shows that changes in zebrafish behavior are highly mixture dependent, and indicate that certain combinations of metals, especially those containing arsenic, cadmium, lead, and uranium, even at levels considered safe in drinking water, are significant drivers of behavioral toxicity. Our data emphasize the need to consider low-level chemical mixture effects and provide a framework for a more in-depth analysis of drinking water samples. We also provide evidence for the efficacy of utilizing citizen science in research, as the broader impact of this work is to empower local communities to advocate for improving their own water quality.
more » « less- Award ID(s):
- 1922560
- NSF-PAR ID:
- 10383577
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Scientific Reports
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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