| (click for larger version)|
A pair of chemicals linked to serious health issues and used for decades to make products ranging from firefighting foam to pizza boxes is being investigated as a source of widespread contamination at military bases and drinking water systems across the country.
Best known by its initials, perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS), the chemicals have been used to make carpets, upholstery, food packaging, cookware and hundreds of other products. In the United States, PFOA was used by DuPont to make Teflon, while PFOS was used by 3M to make Scotchgard. Traces of the man-made chemicals can be detected nearly everywhere in the environment and can be expected to found in everyone's blood.
Due to health concerns, the chemicals have been mostly phased out of production by manufacturers in the United States. But because the chemicals take years to breakdown in the environment and people's bodies, PFOA and PFOS are expected to be chemicals of concern well into the future.
National water sampling directed by the United States Environmental Protection Agency (EPA) in 2013 and 2014 found PFOA and/or PFOS in 52 public water systems in 19 states at levels exceeding federal water advisory limits. The presence of the chemicals has been found in many more public drinking systems, including those in Ann Arbor and Plainfield Township, near Grand Rapids.
Richard Benzie, assistant chief of the Michigan Department of Environmental (DEQ) Quality Drinking Water and Municipal Assistance Water Supply Program, said the EPA advisory isn't a predictor of what the EPA could set regulation levels at in the future, if at all. "The advisory is in no way what the drinking water standard may be," he said. "They must also consider if there is technology to treat these things, and is it cost effective."
For instance, Benzie said the drinking water standard for arsenic is "much higher than if it were based on just health."
"Michigan has a lot of naturally occurring arsenic, and the cost impact to small systems caused them to set it much higher than if it were based on just health," he said. "Those standards don't mean there's no risk at a lower level."
The DEQ adheres to the EPA's drinking water advisory levels for drinking water. However, the state has implemented thresholds for surface water (non-drinking water) in the state at levels of 11 parts per trillion (ppt) for PFOS and 42 ppt for PFOA. However, those levels refer to surface water concentrations, which are predominantly set for fish consumption advisories issued by the Michigan Department of Health and Human Services....continued on page 2