Federal testing of soil samples from 100 sites across New Hampshire has found high levels of per-and poly-fluoroalkyl substances (PFAS) in every sample that was collected, prompting concerns that the amounts of these chemicals in soil, along with water and air, could be much higher than previously thought.
The analysis, done by U.S. Geological Survey, took soil samples across various, undisturbed sites, including forests, shrublands, grasslands, wetlands, herbaceous lands, and barren lands between February 2021 and August 2021. At each location, the researchers took samples up to 6 inches deep. At half of the locations, they also collected samples 6 to 12 inches deep, and at six of these locations, they took samples up to 36 inches deep.
The team found PFAS in all samples, with nearly all of the samples of soil collected up to 6 inches deep containing PFAS at concentrations of 1 part per billion (ppb) to over 10 ppb. While there are not yet PFAS limits regulated at the state or at federal level, the amounts found in the report are higher than recommended by the U.S. Environmental Protection Agency (EPA). The EPA has recently proposed a limit of six types of PFAS in drinking water, with recommended enforceable limits of 1 to 4 parts per trillion of some PFAS.
While there are many known sources of PFAS contamination, including fire suppressants used at local military bases or industrial sources like local manufacturer Saint-Gobain, the study shows these contaminants are not only concentrated near these sources.
It is well known that PFAS transport atmospherically and there is long-range transport of the chemicals, so there might be some influence of local sources but what proportion of PFAS we found is local is not known, Andrea Tokranov, co-author of the study and research hydrologist at USGS.
PFAS are a group of chemicals, often called forever chemicals, that do not break down in the environment. They have been found in soil, water, air, and in the bodies of humans and animals. While research is ongoing, studies have shown possible links between PFAS exposure and negative health risk and outcomes, including decreased vaccine responses in children, higher cholesterol, and some types of cancer.
The report shines a light on the spread of PFAS in the environment, even in places farther from known PFAS polluters, and shows a need for more research into these chemicals, according to State Rep. Rosemarie Rung (D-Merrimack).
When we look at PFAS contamination in New Hampshire, we ve always tracked it to a source, but this study does t show there is one specific source, Rung said, as reported by WMUR.
The report, combined with good tests for PFAS by the Department of Environmental Services, provides more information for the state to establish standards for soil remediation and PFAS regulation.
This information is really informing DES on what those specific contamination levels should be, Rung said.