Assessment of health risks for vulnerable population groups posed by exposure to mercury and its compounds

摘要

Aim: This presentation underlines investigation of mercury (Hg) exposure, effects, and susceptibility in Mediterranean population in early life and compares them with the outcomes of the population living in contaminated site due to historic mercury mining in the town of Idrija, Slovenia. Methods: Maternal hair, maternal and cord blood samples were used to assess prenatal exposure to mercury and its compounds. Children (n=360) were genotyped for apolipoprotein E (Apoe) polymorphism and were assessed for neurodevelopment using Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-lll) at 18 months of age. In a subgroup of pregnant women, the potential interaction of Hg with selenium in plasma (P-Se) and antioxidative enzymes in erythrocytes was also assessed. Results: The main predictor of Hg exposure in the Mediterranean population is fish . consumption demonstrated by large proportion of methyl Hg in the collected samples. Population living in the contaminated site exhibited higher Hg concentrations, but with smaller proportion of Hg as methyl Hg. This indicates the importance of speciation as well as proper use of exposure biomarkers in human biomonitoring programmes in contaminated sites. The results of Bayley III assessment indicated that even low-to-median Hg exposure in children with normal neurodevelopmental outcome can result in lower cognitive and fine motor scores. The Hg-related decrease in cognitive sores was observed in children carrying at least one Apoe e4 allele, while the decrease in fine motor scores was independent of the genotype. The number of examined mother-child pairs from the contaminated site was too small to show any significant effect. However, the internal doses of Hg received during pregnancy in the contaminated site did not decrease the bioavailability of Se, and the decrease in antioxidative capacity appeared to be mainly associated with pregnancy per se and not with an increased exposure to Hg. Conclusion: The studies are on-going in the framework of the EU funded projects, HEALS (Health Environment associations in large population Studies) and Life+ CROME (Cross Mediterranean Heath Environment Network), which use the existing cohorts, and build on novel susceptibility markers and effect testing and integrate them within Health and Environment-wide Associations studies (EWAS) as part of the 'exposome' approach.