Exposure of Mercury Species in Red Blood Cell and the Effects on Metabolites of Residents Living Near Coal-Fired Power Plants

Abstract

BACKGROUND AND AIM: Coal-fired power plant is an important source of mercury for residents nearby. However, it’s still not clear for their exposure of different mercury species and the related health effects. Our study aims to assess the exposures of mercury species in residents near a coal-fired power plant and to clarify the effects of mercury species on metabolite profiles in human body. METHODS: Our study subjects were 152 adult residents living near a coal-fired power plant in central Taiwan, including 76 high-exposure group (HE) and 76 low-exposure group (LE), which were based on previous studies. We detected their inorganic mercury and methyl mercury levels in red blood cells by HPLC-ICPMS and analyzed the differences on levels and ratios between groups by SAS 9.4. The urinary and serum metabolites database of study subjects were established by previous study. MetaboAnalyst 4.0 was used to analyze and visualize the differences in metabolites profiles between the groups with high and low mercury species levels. RESULTS:The levels of inorganic mercury in red blood cells of HE group was significantly higher than those in LE group( 2.48 ± 0.48 µg / L and 1.13 ± 0.60 µg / L respectively) and there was no significant difference between two groups for methylmercury. The ratio of inorganic/total mercury levels were significantly higher in HE group when compared to LE group (12±13% and 7± 6% respectively). There was nine urinary and five serum metabolite profiles were significantly regulated by higher inorganic mercury levels of study subjects. There was no urinary and serum metabolite profiles significantly regulated by different methyl mercury levels. CONCLUSIONS:The levels of inorganic mercury in red blood cells were significantly higher among the residents living closer to the coal-fired power plant, and the higher inorganic mercury exposure might influence the expression of metabolites. KEYWORDS: Coal-fired power plant, Inorganic mercury, Methyl mercury, Metabolomics