Stain repellents linked to low birth weight and premature births.

Dec 07, 2009

Stein, CR, DA Savitz and M Dougan. 2009. Serum levels of perfluorooctanoic acid and perfluorooctane sulfonate and pregnancy outcome. American Journal of Epidemiology 170(7):837-846.

Research finds that stain repellent and anti-adhesive chemicals may be linked to low birth weight and premature births in those born near a factory that both produces and uses the chemicals.

A study that surveyed members of a West Virginia community finds that higher exposures – presumably through water and air – to antistick chemicals released from a nearby factory may be linked to low birth weight and early birth in babies born to women who live in the area.

The synthetic chemicals of concern in the study are called polyfluorinated compounds (PFCs). They are widely used in the manufacture of stain repellents applied to carpets and furniture and as anti-adhesives in pots and pans.

Two of the most common PFCs are perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS). While they are designed for use in product coatings, PFOA and PFOS may also form when other PFCs break down. The chemical plant located near Parkersburg, West Virginia used PFOA since 1951 to make nonstick coatings.

These chemicals are very persistent and have been detected worldwide in wildlife and humans. The most recent National Health and Nutrition Examination Survey (NHANES) reported that virtually all US residents are exposed to PFOA and PFOS.

Animal studies have reported reduced fetal weight and increased neonatal mortality after exposure to high doses of PFCs. Results from previous human studies have been inconsistent.

In this study, women with PFOS blood levels above the median (13.6 nanograms/milliliter (ng/mL)) had a 50 percent increased risk of bearing children with low birth weight and a 10 percent increased odds of giving birth early when compared with women with exposure below the median. These women were also 30 percent more likely to have preeclampsia, which is characterized by high blood pressure during pregnancy and is in turn a risk factor for abnormally slow fetal growth.

No clear associations were reported with PFOA blood levels despite high median levels of exposure in this population (21.2 ng/mL) relative to the general US population (4.0 ng/mL).

Data were collected as part of a survey of more than 69,000 people living close to a chemical plant located in the Mid-Ohio Valley in West Virginia. These data were collected following a class action lawsuit alleging health damage due to exposure to PFOA, which is believed to have occurred through groundwater contamination and air deposition. Researchers measured PFCs in the blood of 1,845 women and obtained information on pregnancy outcomes based on participant interviews.