Temporal Changes in the Levels of Perfluorinated Compounds in California Women's Serum over the Past 50 Years

Serum samples collected from California women at different time
periods: 1960s (n = 40), 1980s (n = 30), and 2009 (n = 35) were examined for the
presence of 12 perfluorinated compounds (PFCs) using an online SPE-HPLC-MS/MS
method. At each time period, perfluorooctane sulfonate (PFOS) was
present at the highest concentration, followed by perfluorooctanoic
acid (PFOA, except in the 1960s). We found the highest levels of PFOS
(median = 42.1 ng/mL) and perfluorohexane sulfonate (PFHxS, median
= 1.56 ng/mL) in the 1960s samples, possibly reflecting widespread
use of precursor PFCs. PFOS showed a statistically significant drop
from the 1960s to the 1980s (28.8 ng/mL ) and to 2009 (9.0 ng/mL ),
the latter being in agreement with national data. For PFOA, there
was an approximately 10-fold increase in median concentrations from
the 1960s (0.27 ng/mL) to the1980s (2.71 ng/mL), and a slight drop
in the 2009 samples (2.08 ng/mL). For longer chain perfluorocarboxylic
acids (PFCAs), there was a continuous build-up in serum from the 1960s
to 2009. To our knowledge, this is the first study to investigate
temporal changes of PFCs over the past 50 years.