Stain-resistant chemicals linked to high blood pressure during pregnancy
Darrow, LA, CR Stein, K Steenland. 2013. Serum perfluorooctanoic acid and perfluorooctane sulfonate concentrations in relation to birth outcomes in the mid-Ohio Valley, 2005-2010. Environmental Health Perspectives. http://1.usa.gov/1aMI1F8
Mothers’ exposure to chemicals that make consumer products stain- and water-resistant was linked to high blood pressure during pregnancy in an analysis of highly exposed communities in West Virginia and Ohio.
The mothers’ levels of perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) levels were associated with an increase in the odds of them experiencing pregnancy-induced hypertension.
Hypertension during pregnancy can be life-threatening for the mother and child. It can prevent the fetus from receiving enough blood, triggering low birth weight. The placenta can also erupt, resulting in serious bleeding in the mother. Seizures, temporary kidney failure, liver and blood clotting problems are also common in the mother.
For the study, PFOS and PFOA were measured in the blood of 1,330 pregnant women who live in the mid Ohio Valley, near the DuPont Co.’s Washington Works factory in West Virginia. The plant has used PFOA in the manufacture of fluoropolymers since 1951, with use peaking in the 1990s.
The drinking water in communities downstream of the plant contains high levels of PFOA. Adults there have approximately 20 times higher PFOA levels in their blood compared to the general U.S. population. The new study is part of a large project, funded by a settlement of a class-action lawsuit against DuPont, to examine human health effects from perfluorinated chemicals.
The women in the study all gave birth between 2005 and 2010; 106 of them, or 6.5 percent, had pregnancy-induced hypertension. Per every log unit increase of PFOS, the women’s odds of hypertension increased 47 percent, and for PFOA, 27 percent.
Most of the births in the study occurred after the mothers’ blood samples were collected, making the study the first prospective assessment of exposure and subsequent birth outcomes in this population.
The study found no connection between the chemicals and incidence of premature births or low birth-weight babies. The study, however, did find a modest, although “not statistically significant” reduction in the weight of full-term newborns associated with increasing PFOS. Previous research in other populations has linked PFOS exposure in the womb to babies born sooner and smaller than babies with lower exposure. The new finding is compatible with the magnitude of associations reported in these other studies, wrote the study's authors.
PFOS and PFOA are synthetic, environmentally persistent chemicals used as water and grease repellents. PFOS, produced by 3M and used in Scotchgard, was phased out in 2001, but remains the predominant PFC in the environment. PFOA is used in Teflon, but is also being phased out.
PFOA exposure has been linked to a number of health effects, including thyroid disease, high cholesterol, early signs of liver damage, testicular and kidney cancer, and pregnancy-induced hypertension and preeclampsia. PFOS exposure has been linked to reduced fertility in men and women, reduced vaccine effectiveness, disrupted thyroid hormones and ADHD symptoms in children.