Residents south of Colorado Springs whose drinking water supply was contaminated with toxic PFASs have high levels of the chemicals in their blood, according to initial results from a study from the Colorado School of Public Health and Colorado School of Mines.
Researchers collected 220 blood samples from people who lived in the Fountain, Security and Widefield communities for at least three years before August 2015. While drinking water in those water systems is now being treated for PFASs, used in Air Force firefighting chemicals, some residents were exposed to the toxic compounds for years before government agencies recognized their potential dangers.
(Wondering why we are now referring to the chemicals as PFASs, though we referred to them as PFCs in other stories? Read this
from the Environmental Protection Agency.)
Little is known about the health effects of PFASs in humans. However, studies on laboratory animals have shown that high concentrations of certain chemicals can cause reproductive and developmental, liver and kidney, immunological effects and tumors, according to the EPA. The most consistent finding among human studies is increased cholesterol, with more limited findings related to cancer, thyroid hormone effects, infant birth weights and adverse effects on the immune system.
The initial results of the study revealed that study participants had blood levels of one toxic compound, PFHxS, that were about 10 times as high as U.S. population reference levels. Levels of this chemical were higher than those for residents in other communities that were highly exposed to PFASs.
Study participants had about twice as much PFOS, another chemical in the PFASs group, as the general population. Previous studies have linked this chemical to thyroid hormone effects in humans.
For study participants, levels of the chemical PFOA — which human studies have linked to cancer — were 40 to 70 percent higher than U.S. levels.
To understand what residents may have been exposed to before water suppliers changed sources or added treatment systems in 2015, researchers also measured PFASs in the untreated wells that communities used prior to that. Total PFASs in the untreated wells ranged from 18 to 2300 ppt.
The Environmental Protection Agency's current acceptable standard for drinking water is 70 ppt, though a June study by the Agency for Toxic Substances and Disease Registry indicated safe levels could be as low as 12 ppt.
Researchers plan to present more results in the first half of 2019, and will begin recruiting more participants for blood sampling in April.
The full presentation from the Colorado School of Public Health and Colorado School of Mines is available on the study website
and embedded below.
See related PDF