A new study has revealed that chemicals used in commercial and industrial applications such as surfactants, paper and textile coatings and food packaging might affect serum cholesterol levels in people.
The polyfluoroalkyl chemicals (PFCs) have been found to be highly persistent in human tissues, with serum elimination half-lives of more than eight years for some types of PFCs. During the study, researchers analysed the relationship between serum concentrations of four PFCs-perfluorooctanoic acid (PFOA), perfluorononanoic acid (PFNA), perfluorooctane sulfonic acid (PFOS) and perfluorohexane sulfonic acid (PFHxS)-and measures of cholesterol, body size and insulin resistance. They found that people with PFOS, PFOA and PFNA levels in the top 25pct of the study population had higher total and non-HDL cholesterol (which is primarily LDL, or “bad” cholesterol) than participants whose PFOS, PFOA, PFNA concentrations were in the lowest 25pct.
While most studies of people with high PFC exposures have also reported positive associations, but the current study suggests that much lower PFC exposures may also affect cholesterol levels.
The association was most striking for PFNA, with a 13.9 mg/dL difference in estimated serum cholesterol levels between people with the highest and lowest serum PFNA concentrations. In contrast, people with the highest levels of PFHxS, a PFC that has not been extensively studied, had lower total and non-HDL cholesterol than those with lower PFHxS concentrations.
“Though these results are based on cross-sectional data and are exploratory, they are consistent with much of the human epidemiologic literature and indicate that PFCs may be exerting an effect on cholesterol at environmentally relevant exposures,” said first author Jessica Nelson and colleagues. “Our study affirms the importance of investigating PFCs other than PFOS and PFOA, particularly as industrial uses of PFOS and PFOA decline and other PFCs are substituted,” they added.