PFOS & PFOA
Two weeks ago, 6.5 million Americans learned that their drinking water is contaminated with man-made chemicals linked to cancer, when the Environmental Protection Agency (EPA) issued a health advisory for two compounds: perfluorooctanoic acid (PFOA), and the related perfluorooctane sulfonic acid (PFOS), used for decades in such consumer products as non-stick pans, stain-resistant carpets and fire fighting foams.
Man-made substances used for decades in countless consumer products,
HIDDEN BY INDUSTRY, UNTESTED BY GOVERNMENT, DANGEROUS FOR YOU
After years of pressure from public health experts and advocacy groups, EPA announced a lifetime drinking water health advisory of 70 parts per trillion for human exposure to the man-made perfluorinated chemicals (PFC), considerably lowering the 2009 provisional health advisory of 400 parts per trillion (ppt).
The Agency said that at this level or below, the chemicals are "not expected to result in adverse health effects over a lifetime of exposure."
Many disagree. Recent studies at Harvard and the University of Massachusetts found that PFOA is hazardous at the tiniest doses - hundreds of times smaller than what the EPA says is safe.
An EPA health advisory is not a regulation; it is not legally enforceable. (EPA has said it could be 2019 or beyond before it sets enforceable drinking water standards). A Health advisory does, however, require a public water system to notify its customers of the presence of the chemical and the dangers it poses.
As a result, the EPA's announcement had a domino effect across the country, sending countless water systems scrambling for solutions. Within hours, residents living near the former Willow Grove Naval Air Station in Horsham were given free bottled water, West Virginia's Bureau for Public Health ordered a “do not drink” advisory for the water in Parkersburg, the site of a Teflon factory, the adjacent town of Vienna; and Martinsburg, near the Maryland border; a drinking water health advisory was issued to Hyannis residents, and the military announced plans to examine 664 sites nationwide to determine whether chemicals from foam used to fight fires have contaminated groundwater and spread to drinking water.
And that's just the tip of the iceberg. According to the Environmental Working Group, since 2013, EPA’s sampling program found PFOA in 52 public water systems serving more than 6.5 million people in 27 states and two Pacific island territories.
Perfluorinated chemicals (PFCs) - The Story
"The PFOS story is likely to emerge as one of the apocryphal examples of 20th century experimentation with widespread chemical exposures: prolific use and almost no testing for safety, until unexpectedly and almost serendipitously, it is discovered as a contaminant virtually everywhere. And as is often the case in these stories, the company producing PFOS products possessed information hinting at its risks but chose not to share their data with regulators or the public for years." - Our Stolen Future by Theo Colborn, Dianne Dumanoski, and John Peterson Myers
PFC is the name given to the broad family of products called perfluorinated compounds. PFOS and PFOA belong to that family. PFOS and PFOA are therefore both PFCs. The difference between family members is primarily determined by how many carbon atoms are in the perfluorinated chain. PFOS and PFOA are both Octyl, that is, they both have 8 carbons. PFOA, formerly used to make DuPont's Teflon, and PFOS, formerly an ingredient in 3M's Scotchgard, are the most prominent members of the perfluorinated chemicals that have been used for decades in hundreds of consumer products and industrial applications. Both chemicals were also used for firefighting at military airfields and commercial airports.
They were phased out after revelations that the manufacturers had withheld decades of studies showing that the chemicals were extraordinarily persistent in the environment and build up in people’s blood. The Center for Disease Control and Prevention says both substances contaminate the blood of almost all Americans and can be passed from mothers to unborn children.
According to the Environmental Working Group's The Inside Story, for decades, the chemical industry has known all too well that some of its products pose risks, both acute and chronic, to human health -- including cancer, endocrine disruption, liver damage, and other serious health problems. Worse, the industry's documents show that chemical companies have gone to great lengths to conceal these dangers from its workers, consumers, and from the public at large.
There are no mandatory pre-market health testing or approval requirements under any US federal law for chemicals in cosmetics, toys, clothing, carpets, or construction materials, to name just a few obvious sources of chemical exposure in everyday life.
The EPA does require some tests for a handful of new compounds (as opposed to heavily used older compounds) via the pre-manufacture notice (PMN) program. These tests provide little protection for the public, however, because they apply only to chemicals that are new and little used, and because studies for critical human health effects like cancer, birth defects, and nervous system toxicity are rarely if ever required.
PFCs in Canada
Like its southern neighbour, Canada has no regulations concerning PFCs in drinking water. In January 2016, at the request of several jurisdictions, Health Canada did develop screening values based on a lifetime's exposure for a number of PFCs. While the department says its values include a margin of
safety (or 'buffer zone') to
protect the health of Canadians, these screening values, 0.2 microgram/litre or 200 parts per trillion (ppt) for PFOA and 0.6 microgram/litre or 600 ppt for PFOS, are more tolerant than the American advisory.
Full health risk assessments are now being developed by Health Canada for PFOS and PFOA as part of the Guidelines for
Canadian Drinking Water Quality. These assessments are expected to be posted for public consultation in
late spring/early summer 2016, and finalized in 2017. Guidelines however are not legally binding.
As is evidenced in the screening levels above, Health Canada does not consider PFOA nd PFOS levels in Canada to be as damaging to human health as does the EPA. Final screening assessment reports conclude that they may have an immediate or long-term harmful effect on the environment or its biological diversity but are not entering the environment in a quantity or concentration that constitute a danger in Canada to human life or health.
Water samples taken for PFOS (not PFOA) between 2007-2011 revealed the presence of PFOS across the country. The
PFOS was highest at a site in Mill Creek, located in Kelowna, B.C (geometric mean = 10 ng/L*). This section of Mill
Creek is urbanized and influenced by urban stormwater. Wascana Creek in Regina, Saskatchewan, located 8.5 km downstream of a wastewater
treatment plant (WWTP) outfall, had a relatively elevated PFOS concentration (geometric mean = 7.8 ng/L*). Detectable values were also observed in southern Ontario (Hamilton Harbour, Niagara River at Fort Erie, Lake Ontario at Wolfe Island, Grand
River and Thames River), St. Lawrence River at Quebec City, Vancouver, BritishColumbia
(Still Creek and Serpentine River), Abbotsford, British-Columbia (Fishtrap
Creek), and at the three Atlantic sites (Napan River, N.B., Sackville River, N.S., and
Waterford River, N.L.).
* NOTE: While Health Canada's screen levels for PFOA-PFOS are given in microgram/L, the concentration here is in nanograms/L. The US calculates concentration in parts per trillion. Health Canada tells us that 0.2 micrograms/L equals 200 parts per trillion. We have found different values online, with one converter givng 200,000 parts per trillion.
We hesitate to convert nanograms/L as we are unsure of the proper conversion. Consistent parameters would be helpful.
While little action was undertaken in Canada to identify and curb the use of PFCs when they first emerged, Canada is the first country in the world to categorize the thousands of chemical substances in use before comprehensive environmental protection laws were created. The results mean that efforts and further research can be focussed on those substances suspected to have the most dangerous properties.
As for new substances coming to market, Canada seems to have a rigourous approval procedure, although it is more likely that new substances would be imported in consumer products than launched in Canada. Here is how the Government of Canada's Chemical Substances website describes the procedure:
"Any company or individual who plans to import or manufacture a substance subject to notification under the New Substances Notification Regulations must provide Environment and Climate Change Canada with a New Substances Notification (NSN) package containing all information prescribed in the Regulations, prior to import or manufacture. When Environment and Climate Change Canada receives a NSN Package from a company or individual proposing to import or manufacture a new substance, a joint assessment process is carried out with Health Canada to determine whether there is a potential for adverse effects of the substance on the environment and human health.
When this process identifies a new substance that may pose a risk to human health or the environment, Canadian Environment Protection Act 1999 empowers Environment and Climate Change Canada to intervene prior to or during the earliest stages of its introduction into Canada."
New chemical substances are created every second around the world, you can watch a real-time CAS counter on the American Chemical Society (ACS) website. In fact, the ACS is currently celebrating the 100th million chemical substance added to its CAS Registry with fun facts such as "more substances were added to the CAS Registry in 2014 than in the combined years from 1965-1990". (NOTE: On May 30 at 6:48 pm, the CAS counter indicated 112,927,700 substances and climbing).
In the US, EPA says there are thousands of known new chemicals it has yet to assess. In Canada, the government's Chemicals Management Plan (CMP) is expected to address the remaining 1550 priority substances out of the original 4300 substances identified as priorities during the categorization, to determine whether they are toxic.
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