| The coal-fired power plant(CFPP)is one of the most anthropogenic sources,from which mercury(Hg)emission could be released into air,leading to water and soil pollution by dry and wet deposition etc.As a result,environmental health problems occur easily with the accumulation of biological chains.Therefore,investigating the human health risk assessment around the CFPP is of great importance.Based on the CFPP in the coastal area of Southeast China,total mercury(THg)and methyl mercury(MeHg)concentration of environment mediums,crops,aquatic products and hair was analyzed.Systemic cluster methods,correlation and variance analysis were adopted in order to find the biological enrichment characteristics and explore the influence of different factors towards THg and MeHg concentration among vegetables,aquatic products and hairs.A Monte Carlo simulation method of Crystal Ball Software was adopted in order to assess the daily intake and non-carcinogenic risk in residents around the CFPP.The key findings of the survey were included as follows:(1)The concentration of particle Hg(Hg(P))in PM2.5 and PM10 was 264.92±40.44 pg/m3 and 336.06±73.13 pg/m3.Compared with other coastal cities,there was atmospheric mercury pollution to some extent.The concentration of THg was 41.71±25.28 ng/L and 0.71±0.12 ng/L,and the concentration of MeHg was 0.85±0.34 ng/L and 0.12±0.06 ng/L in surface water and drinking water.The concentration of THg was 0.153±0.126 mg/kg,and the concentration of MeHg was 0.95±0.14 ng/g in soil.The concentration of THg exceeded the limits of agricultural soil in Zhejiang province,and there was increasing trend of THg in the topsoil.The partition coefficient of residuals(81.22%± 11.72%)contributed most in all fractions,which indicated the poor bio-availability in soil.The concentration of THg(dry weight)was 23.54±14.56 ng/g in local vegetables,and leafy vegetables>eggplant vegetables>tuber vegetables.The concentration of MeHg was 2.43±0.80 ng/g,and eggplant vegetables>leafy vegetables>tuber vegetables.Besides,the concentration of MeHg in local vegetables was higher than that in the market.The average enrichment coefficients of THg and MeHg were 21.43%±13.48%and 2.65±0.87 in vegetables around the CFPP,and vegetables had a higher enrichment capacity of MeHg.Leaf vegetables had a better enrichment ability of THg than eggplant vegetables,while eggplant vegetables had a better enrichment ability of MeHg than leaf vegetables.The concentration of THg in bell peppers as well as the concentration of MeHg in radish had significantly positive correlation with the concentration of PM2.5 and PM10.The concentration of THg in amaranth as well as the concentration of MeHg in corn had significantly positive correlation with the concentration of THg and MeHg in soil.They might be the result of the transition and redistribution of THg and MeHg between the atmospheric mercury absorbed by leafs and the soil mercury absorbed by roots.(2)The concentration of THg(fresh weight)was 32.61±30.33 ng/g,and the concentration of MeHg was 30.08±31.09 ng/g,as well as other ocean organisms>marine fishes>freshwater fishes>other freshwater organisms.The average enrichment coefficients of THg and MeHg were 2.07×104±2.39×104 and 3.46×105±3.99×105 in aquatic products around the CFPP,and aquatic products had a higher enrichment capacity of MeHg.The concentration of THg and MeHg in marine aquatic products was higher than that of freshwater,and bottom layer>middle and lower layer>pelagic layer.The concentration of THg and MeHg of fleshing-eating aquatic products was higher than that of plant-eating aquatic products,and fleshing-eating>omnivore,filter>plant-eating.The concentration of THg and MeHg of top trophic level was higher than that of medium and bottom trophic levels.The concentration of THg and MeHg had significantly positive correlation with body length,whereas had weak correlation with body weight.The concentration of THg was 0.873±0.411 ?g/g,of which the sample rate above the standard was 25.37%and the concentration of MeHg was 0.496±10.267 ?g/g.The concentration of THg and MeHg in male hair was higher than that of women,among which there was a significant difference.Prior to the age of fifty five,the concentration of THg increased with the increasing of age,and then decreased slowly.The concentration of MeHg was significantly and positively correlated with the age.Compared with other groups,the concentration of THg and MeHg was higher in obesity,and had significantly positive correlation with body weight and BMI.They might be the result that MeHg had high fat solubility and could be stored in fat more easily.Regional environment,occupational exposure and living habits also had an impact on THg and MeHg levels.The concentration of THg in drinking group also had a significant difference with that in non-drinking group.Besides that,there was a significant difference among population of different quantity of fish-eating,and the concentration of THg and MeHg had significantly positive correlation with the quantity of fish-eating,which indicated that fish consumption was one of the most important factors.(3)The high THg exposure in children(0-5 years)group exceeded the limits of PTWI,which indicated that there was a risk of THg intake,and there was no risk of THg in other groups.Besides,the high MeHg exposure in children group exceeded the limits of PTWI,which indicated that there was a risk of MeHg intake,and there was no risk of MeHg in other groups.The contribution of ingestion pathway and food medium was the highest(>99.9%),and the aquatic products had the largest proportion in the food.Besides that,the HI values among the high THg exposure in children group was greater than I,which indicated that there was a non-carcinogenic risk of THg,and there was no risk of THg in other groups.The HI values among the high MeHg exposure in children(0-5 years)group was greater than 1,which indicated that there was a non-carcinogenic risk of MeHg,and there was no risk of MeHg in other groups. |
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