Human Metabolic Responses to Chronic Environmental Polycyclic Aromatic Hydrocarbon Exposure by a Metabolomic Approach

The toxicities of polycyclic aromatic hydrocarbons (PAHs) have been extensively explored due to their carcinogenic and mutagenic potency; however, little is known about the metabolic responses to chronic environmental PAR exposure among the general population. In the present study, 566 healthy volunteers were dichotomized into exposed and control groups to investigate PAR-induced perturbations in the metabolic profiles. Nine urine PAR metabolites were measured by a sensitive LC-MS/MS method to comprehensively evaluate the PAR exposure level of each individual, and the metabolic profiles were characterized via a LC-MS-based metabolomic approach. PAR exposure was correlated to its metabolic outcomes by linear and logistic regression analyses. Metabolites related to amino acid, purine, lipid, and glucuronic acid metabolism were significantly changed in the exposed group. 1-Hydroxyphenanthrene and dodecadienyl-carnitine have potential as sensitive and reliable biomarkers for PAN exposure and its metabolic outcomes, respectively, in the general population. These findings generally support the hypothesis that environmental PAR exposure causes oxidative stress-related effects in humans. The current study provides new insight into the early molecular events induced by PAR exposure in the actual environment.