Toxic Tuesdays

Arsenic is a naturally-occurring element found in the Earth’s crust. It has some industrial uses through which people can become exposed to it. In some places, like northern New England, arsenic is present in bedrock, and drinking water wells drilled in these areas can expose people to arsenic in their water. Arsenic is classified as a human carcinogen, meaning exposure to it can cause cancer. Skin, liver, bladder, and lung cancer are the most commonly reported cancer types. In northern New England states (Maine, New Hampshire, and Vermont), mortality rates from bladder cancer are much higher than they are across the US as a whole, and it is thought that the reason is long-term exposure to arsenic in well water. Some wells in these states have arsenic levels over 1,000 times the safe limit set by the US Environmental Protection Agency (EPA).

Arsenic exposure through well water is a serious concern, but the full extent of the problem in northern New England isn’t known. This is because it is difficult to test all drinking water sources in a large, rural geographic area, and because about half of homes in Maine and New Hampshire receive water from private wells which are not subject to regulation by the government. A recent study called the All About Arsenic (AAA) program used citizen science to collect data on arsenic in well water in Maine and New Hampshire and help raise community awareness about mitigating arsenic exposure.

Citizen science is scientific research conducted with the participation of the general public. Research has shown that citizen science can generate new knowledge, create learning opportunities for participants, strengthen community relationships, promote participation in civic life, and address environmental health concerns. In the AAA program, the researchers recruited teachers from a large geographic area in Maine and New Hampshire and paired them with scientist partners from nearby colleges. They developed water sample kits for the teachers’ students to use to collect water samples from their homes and their neighbors’ homes. Samples were analyzed for metals by scientists and results were shared with the teacher and student participants. Teachers and students then prepared community education materials so that classmates, parents, neighbors, local news, and local elected officials would know and understand the results.

The AAA program recruited a total of 31 teachers and 4,859 middle and high school students. Students collected 3,070 drinking water samples from 2016-2022, and 15% exceeded the EPA’s limit for arsenic in drinking water. These samples represented a significant increase in wells in Maine and New Hampshire that now have data regarding their arsenic levels. In some towns, the AAA program more than doubled the number of samples the states previously had. In other towns the AAA sampled, the states previously had no data. In one town, before the AAA program it was not known that arsenic levels exceeded the EPA’s limit. Consistent with the idea that the source of arsenic in these samples is from bedrock, samples that receive water from drilled wells tended to have higher arsenic concentrations.

The AAA researchers used surveys and interviews to follow up with some households whose water was sampled. Of 72 households surveyed, 29 (40%) took actions to mitigate their exposure to arsenic in their water after receiving their sampling results. Some survey respondents said they had no prior knowledge about arsenic in their well water. Mitigating actions included upgrading their systems, installing point-of-use filters, and using bottled water for drinking. Interviews with households confirmed that the AAA program had direct public health and educational impacts on those that participated in the study. Interviewees specifically mentioned that health risks to their families and children were their main concerns that drove their decision-making after receiving their sampling results.

The AAA program provides valuable insights beyond simply generating more data. It shows that are ways to collect data and disseminate information in communities – like large rural areas – that have been previously underserved by public health agencies. It also demonstrates that communities can and should be crucial partners in every stage of the process, not simply as study subjects. The AAA program involved teachers and students in study design, sample collection, sample analysis, communication of results, and community education, reflecting a true citizen science partnership. Finally, the study demonstrates that there is more environmental exposure to toxic chemicals than we have previously been aware of. Data collection alone won’t change this, so taking action to protect communities is essential. The AAA program shows that when given information about their potential arsenic exposure, many residents took action to protect themselves. However, relying on individual residents to spend time and money on their own arsenic mitigation strategies cannot be the only solution. Using data like that collected in the AAA program, local, state, and federal agencies must monitor, regulate, and provide mitigation equipment for private water wells like they do for public wells. This will be the best way to keep communities safe from arsenic in their drinking water.

CHEJ has previously written about other sources of arsenic exposure here.