Association of Perfluorooctanoic Acid with HDL Cholesterol and Circulating miR-26b and miR-199-3p in Workers of a Fluorochemical Plant and Nearby Residents

Perfluoroallcyl chemicals (PFCs) are stable man-made compounds with many industrial and commercial uses. Concern has been raised that they may exert deleterious effects, especially on lipid regulation. We aimed to assess exposure to perfluorooctanoic acid (PFOA), perfluorooctane sulfonic acid (PFOS), and seven other PFCs in occupational workers from a fluorochemical plant and nearby community residents, and to investigate the association between PFOA and serum biomarkers. Serum biomarkers included not only biochemical parameters, such as lipids and enzymes, but also circulating microRNAs (miRNAs). Samples were analyzed by high-pressure liquid chromatography/tandem mass spectrometry (HPLC-MS/MS). Circulating miRNA levels were detected by quantitative polymerase chain reaction (PCR). Analyses were conducted by correlation and linear regression. We detected PFOS, PFOA, perfluorohexane sulfonate (PFHxS), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PFDA) in all samples. The median levels of serum PFOA and PFOS were 284.34 ng/mL and 34.16 ng/mL in residents and 1635.96 ng/mL and 33.46 ng/mL in occupational participants, respectively. To our knowledge, we found for the first time that PFOA was negatively associated with high-density lipoprotein cholesterol (HDL-C) in workers using linear regression after adjusting for potential confounders. Circulating miR-26b and miR-199a-3p were elevated with serum concentration of PFOA. Although the limitations of small sample size and the cross-sectional nature of the current study constrained causal inferences, the observed associations between PFOA and these serum biomarkers warrant further study.