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Serum Concentrations of 11 Polyfluoroalkyl Compounds in the U.S. Population: Data from the National Health and Nutrition Examination Survey (NHANES) 1999−2000
journal contribution
posted on 2007-04-01, 00:00 authored by Antonia M. Calafat, Zsuzsanna Kuklenyik, John A. Reidy, Samuel P. Caudill, Jason S. Tully, Larry L. NeedhamWe measured the concentrations of 11 polyfluoroalkyl
compounds (PFCs), including perfluorooctane sulfonic acid
(PFOS), perfluorooctanoic acid (PFOA), and perfluorohexane
sulfonic acid (PFHxS) in 1562 serum samples collected
from a representative U.S. population 12 years of age and
older in the 1999−2000 National Health and Nutrition
Examination Survey. Participants represented both sexes,
three race/ethnicities (non-Hispanic blacks, non-Hispanic
whites, and Mexican-Americans), and four age categories
(12−19 years, 20−39 years, 40−59 years, and 60 years
and older). PFCs were extracted from 100 μL of serum using
on-line solid-phase extraction coupled to isotope dilution-high performance liquid chromatography-tandem mass
spectrometry; limits of detection ranged from 0.05 to 0.2 ng/mL. PFOS, PFOA, PFHxS, and perfluorooctane sulfonamide
were detected in all samples analyzed; 2-(N-ethyl-perfluorooctane sulfonamido) acetic acid, 2-(N-methyl-perfluorooctane sulfonamido) acetic acid, and perfluorononanoic acid were detected in more than 90% of samples,
which suggests prevalent exposures to several PFCs in
the U.S. population. The concentrations of most PFCs were
similar regardless of the participants' ages but were
higher in males than in females. Mexican Americans had
lower concentrations than non-Hispanic blacks and non-Hispanic whites, whose concentrations were similar. Higher
education was associated with higher concentrations of
PFOS and PFOA. These data will serve as a nationally
representative baseline of the U.S. population's exposure
to PFCs to which other populations can be compared, and
will play an important role in public health by helping
set research priorities, ranging from health effects studies
to defining sources and pathways of exposure.