Kwiaht launches arsenic testing and action project

||| FROM RUSSEL BARSH for KWIAHT |||

Islands conservation laboratory Kwiaht is seeking participants in a study of the extent of arsenic contamination in island wells, and actions to reduce adverse health effects Islanders may be at increased risk of colon cancer due to the widespread presence of
small amounts of arsenic in the islands’ well water. Although the regulatory ceiling for arsenic in drinking water is 10 parts per billion (ppb) in Washington State, concentrations as low as one or two ppb can adversely affect human health. Since arsenic bioaccumulates, long term exposure to low levels of arsenic in drinking water or food supplies have been linked to cardiovascular and neurodegenerative diseases as well as cancer, according to the World Health Organization.

Although arsenic may be present in emissions from fossil-fuel power plants and smelters, dispersed by winds and deposited in rainfall, it is most often encountered as a natural constituent of groundwater. Under certain conditions, arsenic accumulates in sediments that may eventually become sedimentary rocks, such as some of the shales underlying much of the San Juan Islands. Continental glaciers crushed and flooded our bedrock, creating the rock-fissure aquifers that are the source of well water throughout much of San Juan County today.

This kind of aquifer is likely to re-dissolve arsenic, releasing it into streams and wells. A 2021 U.S. Geological Survey report estimated that 30 million Americans in formerly glaciated areas, including Washington State, are affected.

Not all wells in the San Juan Islands have measurable levels of arsenic. Data collected by Kwiaht and Western Washington University in 2008 suggested that about 10 percent of wells at that time were affected, mainly in four distinct subregions of the county. Since then, however, a number of factors have likely increased islanders’ exposure to arsenic. Groundwater withdrawals can increase seawater intrusion and elevate arsenic levels. More wells have been drilled in areas that Kwiaht flagged in 2008. Climate change is meanwhile likely to reduce recharge rates.

In the meantime, San Juan County has developed one of the state’s highest rates of colon cancer, judging from Washington Department of Health statistics.

With a grant from Washington State’s new environmental-justice law, the HEAL Act, and in collaboration with colleagues at the University of Washington and Fred Hutch Cancer Center, Kwiaht has begun a more intensive survey of arsenic in the islands’ wells, with the ultimate goal of developing a community-led response that may include mitigation, alternative water
supplies, and preventive medicine. Kwiaht joins thirty other Washington State nonprofits that are pursuing local water-quality issues and have committed to working together on research and action.

The first step is empowering islanders to test their own well water using the most reliable available home test kits, which Kwiaht will distribute free to participants at workshops organized on Lopez, Orcas and San Juan Islands this autumn.

Once they have tested their wells themselves, participants will have the option of taking well water samples to “open lab” sessions where Kwiaht researchers use the latest EPA-certified benchtop technology to verify and improve the precision of home test results. Further testing using “gold standard” instruments at Fred Hutch will also be available at no cost to participants. Kwiaht will also provide free filtration supplies where needed.

Workshops on the causes, consequences, measurement and mitigation of arsenic in well water will be held at Lopez Library on October 1 from 4:00 to 6:00 pm and November 14 from 3:00 to 5:00 pm; at Orcas Island Library on October 10 from 1:00 to 3:00 pm and October 29 from 4:00 to 6:00 pm; and at San Juan Island Library on November 21 from noon to 2:30 pm and December 3 from 3:00 to 5:00 pm. (Libraries are not sponsors of this project.) Home test kits will be available at all workshops.