NMR-based metabolomic analysis of human plasma to examine the effect of exposure to persistent organic pollutants

Persistent organic pollutants (POPs) are lipophilic environmental toxins, and the level of chemicals accumulated in the body through the food chain has been linked to the incidence of diseases such as type 2 diabetes, car-diovascular disease, and cancer. We analyzed the concentration of POPs and circulating metabolites and investigated the associations between the concentration of plasma metabolites and the levels of polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) to determine the effect of the accumulation of POPs in human samples. Metabolic profiling of plasma from 276 Korean participants was performed using 1H nuclear magnetic resonance (NMR) and statistical analyses. The concentrations of PCBs and OCPs in each sample were measured. Correlation analysis and a covariate-adjusted general linear model (GLM) were used to investigate the association of the concentration of POPs with circulating metabolites in human blood samples. We found that four categories of E6PCBs and E5OCPs based on rank were significantly correlated with 4 and 5 metabolites, respectively, after adjusting for confounding factors, including age, sex, body mass index (BMI), smoking status, alcohol intake, physical activity, triglycerides, and total cholesterol. According to the GLM analyses, 3 metab-olites, namely, creatinine, acetate, and formate, among the 4 correlated metabolites were associated with four categories of rank-based E6PCBs. On the other hand, the quartiles of the rank-based E5OCPs were not associated with any circulating metabolites among the 5 correlated metabolites. Our findings indicate that the metabolites related to short-chain fatty acids and creatine can be useful risk indicators for estimating the effect of PCB exposure.