In
this study, serum and urine samples were collected from 36 occupational
workers in a fluorochemical manufacturing plant in China from 2008
to 2012 to evaluate the body burden and possible elimination of linear
and branched perfluoroalkyl acids (PFAAs). Indoor dust, total suspended
particles (TSP), diet, and drinking water samples were also collected
to trace the occupational exposure pathway to PFAA isomers. The geometric
mean concentrations of perfluorooctanesulfonate (PFOS), perfluorooctanoate
(PFOA), and perfluorohexanesulfonate (PFHxS) isomers in the serum
were 1386, 371, and 863 ng mL<sup>–1</sup>, respectively. The
linear isomer of PFOS, PFOA, and PFHxS was the most predominant PFAA
in the serum, with mean proportions of 63.3, 91.1, and 92.7% respectively,
which were higher than the proportions in urine. The most important
exposure routes to PFAA isomers in the occupational workers were considered
to be the intake of indoor dust and TSP. A renal clearance estimation
indicated that branched PFAA isomers had a higher renal clearance
rate than did the corresponding linear isomers. Molecular docking
modeling implied that linear PFOS (<i>n</i>-PFOS) had a
stronger interaction with human serum albumin (HSA) than branched
isomers did, which could decrease the proportion of <i>n</i>-PFOS in the blood of humans via the transport of HSA