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PFOA, a chemical
found in products ranging from clothes to stain repellents
to food packaging and cosmetics, and a component of Teflon
production, poses developmental and reproductive risks to
humans, according to a risk assessment form the U.S. Environmental
Protection Agency (EPA).
Current PFOA exposures
in children may be well above safe levels, and some children
have high enough blood levels of PFOA to cause serious toxicity
in laboratory studies.
The EPA reviewed
PFOA after "unexpected toxicological and bioaccumulation
discoveries" in the entire class of perfluorinated chemicals,
particularly PFOS (perfluorooctane sulfonates), the active
ingredient in Scotchgard, which was removed from the market
by the EPA in 2000.
PFOS has similar
chemical properties to PFOA. Neither product breaks down in
the environment and both cause various cancers and adverse
effects.
In animal studies
PFOA has been associated with:
- "Significant
increases in treatment related deaths" in rat offspring
at doses that did not affect the mothers
- Serious changes
in the weight of various organs, including the brain, prostate,
liver, thymus, and kidneys
- The deaths of
a significant number of rat pups of mothers that had been
exposed to PFOA
- Damage to the
pituitary at all doses in female rat offspring (The pituitary
secretes hormones that regulate growth, reproduction, and
many metabolic processes. Change in pituitary size is associated
with toxicity)
Other unrelated
studies have also found evidence of birth defects in babies
from PFOA-exposed workers. In 1981, two out of seven women
who worked at a DuPont Teflon plant gave birth to babies with
birth defects. DuPont then moved 50 women workers at the plant
to reduce their exposure to PFOA.
Additionally, PFOA
has been associated with tumors in at least four different
organs in animal tests, and has been associated with increases
in prostate cancer in PFOA plant workers.
The potentially
harmful effects of PFOA are heightened because exposure is
so widespread. Some 90 percent of the U.S. population has
PFOA in their blood, some at levels as high as those found
in PFOA factory workers.
According to the
EPA, it is not known how humans are generally exposed to the
substance. However, it has been suggested that PFOA’s
longevity could be a contributing factor.
Unlike PCBs and
DDT, PFOA does not break down in the environment, so it is
infinitely persistent. Additionally, other classes of chemicals
break down into PFOA, which means that even if PFOA were banned,
levels of the substance in the environment could still increase
due to the other chemicals.
In short, all of
the PFOA generated by industries will remain in the environment
indefinitely.
Although PFOA and
related chemicals have been widely used in consumer products
for 50 years, risks posed by such chemicals have only recently
been exposed. Industry is not required to conduct safety tests
on chemicals like PFOA in order to sell or use them. Due to
this lack of regulatory authority, the EPA’s influence
over chemical manufacturers is largely limited to requests
for data once contamination creates a problem.
Environmental
Working Group March 28, 2003
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