The Emergence of “Emerging Contaminants”

The EPA in 2006 made a deal with eight American companies that make or use perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) to stop doing so. These chemicals are parts of a larger class of chemicals  known as perfluorinated chemicals (PFCs), which in turn falls under the larger group heading of “emerging contaminants.” Emerging contaminants are defined as materials having “a perceived, potential, or real threat to human health or the environment.”

The companies say that they have complied, but the EPA has made little progress in setting up any real standards or guidelines about the dangers of lifetime exposure to the chemicals.

There is a need for such determinatation, since these man-made chemicals have been linked to a disturbing array of health effects, including obesity in children, reproductive problems and cancers. Used as a surface-active agent in a slew of products from coating additives – like Teflon – to cleaning products, these compounds don’t break down under typical conditions and are extremely persistent in the environment, says the EPA.

And while PFCs may no longer be in active production, they are still being used. And, as we’re learning, there is no scarcity of them.

Telflon used in cookware coating, that was generally regarded as safe for many years, is no longer considered so. Teflon has been much in news.  Far less publicized, outside the areas where it is being found in water supplies, mostly around military bases, is PFC-containing firefighting foam.

When jet fuel burns, it makes a fire that isn’t easy to put out. Water doesn’t work. So, half a century ago the 3M Corporation, with the encouragement of the US Navy, developed a product known as AFFF (Aqueous Film-Forming Foam) to put out airplane crash fires. AFFF contains PFOS and other compounds that break down to PFOA and other PFCs.

For years AFFF has been used to put out fires and even more widely in training exercises, demonstrations, and testing activities on military bases around the nation. So it is not surprising that communities near military bases are finding PFCs in the soil and in their drinking water. With a lack of concern that has been characteristic of the military in matters of water safety, no effort was made to construct barriers to contain the foam, which sank down through the earth into the water table.

According to a  Provisional Health Advisory issued by the EPA in 2009, the maximum levels that humans should be exposed to through drinking water is 0.2 ppb for PFOS and 0.4 ppb for PFOA. Although the agency has said repeatedly that it will update these numbers, it hasn’t done so since 2009.

According to one researcher, “In some of these places, huge amounts of chemicals from the foam have been found in soil and water. At Tyndall Air Force Base in Florida, for instance, one of the telomers that can decay into a chemical similar to PFOA was found at 14,600 ppb. Near the Naval Air Station in Fallon, Nevada, where fire-training exercises were conducted for more than 30 years, PFOA has been recorded in the groundwater at levels as high as 6,720 ppb. And, at the former Wurtsmith Air Force Base in Michigan, where crash trainings also took place for more than three decades, one plume of groundwater had concentrations of total PFCs between 100,000 and 250,000 ppb.”

While advanced countries like Sweden, the EU, and Canada have banned the use of existing stockpiles of foam containing PFOS, the US has no restrictions on its use. The US military has a stockpile of a million gallons.

Home water treatment for PFCs in drinking water? Studies done by the Minnesota Department of Health find that both carbon filtration and reverse osmosis effectively remove PFCs.

Reference: Treehugger.com.