The association of organophosphate flame retardants (OPFRs) exposure on omega-3 fatty acids metabolism: evidence derived from the United States general population

Abstract

This study investigated the association between exposure to organophosphate flame retardants (OPFRs) and serum omega-3 fatty acid levels in the general U.S. population, using data from 1,350 adults in the 2011-2014 National Health and Nutrition Examination Survey (NHANES). OPFRs are widely used in consumer and industrial products, and emerging evidence has linked them to disruptions in lipid metabolism. In this study, urinary concentrations of five OPFR metabolites were analyzed in relation to serum levels of key omega-3 fatty acids, including eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and docosapentaenoic acid (DPA), with adjustment for potential confounders. We observed significant negative associations between higher levels of diphenyl phosphate (DPhP) and the concentrations of EPA, DHA, and DPA. Similarly, bis(1,3-dichloro-2-propyl) phosphate (BDCPP) was negatively associated with EPA, bis(1-chloro-2-propyl) phosphate (BCEP) with DHA, and dibutyl phosphate (DBUP) with alpha-linolenic acid and DPA. Participants in the highest quartiles of DPhP and BDCPP exposure showed 18.2 and 18.4% lower EPA levels compared to the lowest quartiles, respectively. DHA levels declined by 17.5% with increasing DPhP and by 9.4% with sum of OPFRs (ΣOPFRs). These findings suggest that environmental OPFR exposure may interfere with omega-3 fatty acid metabolism and highlight potential metabolic and cardiovascular risks associated with these widely used flame retardants. These results underscore the importance of continued environmental monitoring and research into the health effects of OPFRs, particularly as their global use and human exposure continue to rise.

Keywords: bis(1,3-dichloro-2-propyl) phosphate; diphenyl phosphate; docosapentaenoic acid; eicosapentaenoic acid; omega-3 fatty acid; organophosphate flame retardant exposure.

Fig. 1

Participant flow chart algorithm.

Fig. 2

Mean and SE of eicosapentaenoic acid, docosahexaenoic acid, stearidonic acid, and docosapentaenoic acid across quartiles of OPFRs in linear regression models, with results weighted for sampling strategy. A) Diphenyl phosphate (DPhP), B) bis(1,3-dichloro-2-propyl) phosphate (BDCPP), C) bis(1-chloro-2-propyl) phosphate (BCPP). Mean and SE of eicosapentaenoic acid, docosahexaenoic acid, stearidonic acid, and docosapentaenoic acid across quartiles of OPFRs in linear regression models, with results weighted for sampling strategy. D) bis(2-chloroethyl) phosphate (BCEP), E) di-n-butyl phosphate (DnBP), and sum of OPFRs (ΣOPFRs).