FEATURE
a Safe Drinking Water Act maximum
contaminant level for PFOA and PFOS,
a final determination and enforceable
regulation are likely years away.
advise clinical response, because there’s
so little known about PFAS clinically. We
don’t know what a level in the blood may
mean in terms of past exposure, current
risks or future health outcomes.”
NHANES data are, however, critical
for establishing national background
levels—against which local test data can
be compared to identify cases of elevated
exposure—and for monitoring exposure
trends. For example, after manufacturers
began voluntarily phasing out use of
PFOS around 2000, average US blood
concentrations fell by more than 80% over
the next 14 years.
Yet CDC tracks only a small handful of
the thousands of PFAS compounds in
existence.
The California Department of Public
Health (CDPH)—the first state to begin
population-wide PFAS biomonitoring—
noted in an e-mail the challenges
associated with this broad class of
chemicals:
“Developing methods to identify and
measure new compounds is difficult and
time consuming, all the more so because
we usually do not know what compounds
are being used commercially. There are
also many analytical complications.
Analytical standards (needed for method
development) are not readily available.
Some of the newer replacement PFAS,
such as shorter chain and ether-based
compounds, require specialized analytical
methods to detect, and there isn’t a
consensus yet about how to interpret and
report results. These issues are difficult
to resolve, and new chemicals are being
used in products and released into the
environment every day.”
The environmental side of the issue is
similarly fraught. In 2016, EPA lowered
its drinking water health advisory
limit for PFOS and perfluorooctanoic
acid (PFOA)—two of the best studied
PFAS legacy compounds—from 200
ppt PFOS and 400 ppt PFOA down to 70
ppt for both chemicals combined. But
this is a nonbinding limit. (A draft CDC
toxicology report released last June
suggests a much lower lifetime exposure
limit for the same compounds.) While
the agency is evaluating the need for
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In the meantime, EPA is also developing
draft toxicity values for the PFOS/PFOA
replacement chemicals GenX (HFPO dimer
acid) and perfluorobutane sulfonic acid.
In the absence of stronger federal
action, states have begun their own
PFAS monitoring and interventions. Last
June, for example, the North Carolina
Department of Environmental Quality
filed a court order requiring Chemours
Company—a DuPont spinoff—to
drastically reduce its release of GenX and
other PFAS into the air and into the Cape
Fear River watershed, where they had
contaminated drinking water supplies
and alarmed residents. Local communities
blame GenX for a cluster of unexplained
pediatric cancer cases there.
NCSL’s Farquhar said, “People are very,
very concerned. They want a solution.
North Carolina is not known as a very
environmentally rigorous state, which is
probably part of the reason [Chemours]
built there. Now [the issue has] come back
to the state. The public is just up in arms.”
Last February, 3M agreed to pay the
state of Minnesota $850 million to
settle a lawsuit related to PFAS drinking
water contamination in the area
surrounding the company’s Cottage Grove
manufacturing plant, just ten miles south
of St. Paul.
A notable feature of the policy
environment, said Farquhar, is that
PFAS are a “very bipartisan” issue, as
“reflective of public opinion.” He said,
“The state legislatures are not waiting
for the federal government. It’s not that
they don’t trust the government, they’re
just moving ahead.”
During 2017-2018, at least ten states
(CA, MI, MN, NC, NH, NY, PA, RI, VT, WA)
enacted PFAS-related laws. Washington,
for example, passed legislation banning
the use of certain PFAS-containing food
packaging and severely restricting the sale
and use of PFAS-containing firefighting
foam, beginning in 2022 and 2020,
respectively.
APHL.org
A 96-well extraction plate showing serum extraction
(before and after). Proteins and fats are removed leaving a
cleaner sample extract (upper panel) for analysis using high
through-put instrumentation. Photo: Wadsworth Center
Other states have instituted drinking
water standards more stringent than EPA’s
70 ppt health advisory level for PFOS and
PFOA. For example, California requires
public drinking water systems to notify
residents when PFOA exceeds 14 ppt or
PFOS exceeds 13 ppt. Vermont allows no
more than 20 ppt for the sum of five PFAS,
including PFOS and PFOA. New Jersey has
a 13 ppt limit for perfluorononanoic acid,
a particularly toxic PFAS discharged into
the southern Delaware River area by a
specialty polymers plant.
“Everyone carries a body burden of
these persistent chemicals”
Michigan began detecting PFAS in
sites around the state as early as 2012,
beginning with the area around the
Wurtsmith Air Force Base (WAFB) in
Oscoda and the Army & Air National
Guard Training Center at Camp Grayling.
“We learned the military, right about that
time, had begun to test their bases for
PFAS, because firefighting foams carry
these ‘forever’ chemicals, and they have
to do a lot of training and put out a lot
of fires,” said Wells. “After that, we had
citizen concerns.”
Winter 2019 LAB MATTERS
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