| This research described the extents and distributions of mercury pollution in water, benthic mud,aquatic organisms, bamboo soils and bamboos; gave primary assessment of mercury exposure to localresidents by energy-saving lamps production. The results are following as below:(1) The contents of total mercury (THg) in waters of fluorescent lamps production districtsshowed an increasing trend: upstream <fluorescent lamps production districts <confluence of tworivers, from1.1to38ng·L-1. According to EPA standards, concentration of THg over12ng·L-1willresult in chronic toxicity to aquatic organisms, which indicated that the aquatic organism in12.5%ofsmapling points were affected by Hg contamination in this study. In addition, the concentration ofmethylmercury (MeHg) is as low as0.063to1.2ng·L-1. Particulate mercury (PHg), dissolvedmercury(DHg) and MeHg had significantly positive correlations with THg (p<0.0001). Moreover,significant positive correlation (R=0.68, p<0.05, N=11) was observed between THg in water andsediment. MeHg could be accumulated in aquatic organisms through bioaccumulation andbiomagnification. The production of fluorescent lamps significantly result in the accumulation of Hg inlocal aquatic organisms, especially for river snails. THg (205.67-1436.67ng·g-1) and MeHg(31.38-403.72ng·g-1) in the river snails were much higher than those in Lengshui River in HunanProvince, but less than national standards of contaminations in food of China (500ng·g-1,GB2762-2012). Hg in aquatic weed mainly existed in leaves or roots, with different enrichment featuresbetween Chou river and You river.(2) THg and MeHg in bamboo growing system, including soil, root, leaves and branches, fromfluorescent lamps production were invested. Soil samples in which THg was higher than150ng·g-1were close to moderately polluted soils around one thermometer factory, but less than Hangzhou andglobal soil background values. THg in soil from Chou river district were higher than You river district,which indicated the influence of fluorescent lamps activities on Hg contamination in soil. Meanwhile,no significant difference for THg in bamboo soils among four seasons. In comprison, MeHgconcentration in bamboo soils in spring and summer are significant higher than autumn and winter.Furthermore, Hg was enriched in bamboo leaves and bamboo had strong enrichment of Hg than otherplants. THg in bamboo organs varied with seasons: in leaves (spring> autumn> winter> summer), in branches (autumn> spring> winter> summer), in roots (winter> autumn, no significance).(3) THg in hairs of local residents exhibited district features with high content were noted in mostfluorescent lamps production factories located in. THg in local rice samples (12.57±6.9ng·g-1) weresignificant higher than non-local rice (9.34±6.19ng·g-1), but not for MeHg. THg and MeHg in hairs ofresidents eating non-local rices (728.22±496.56ng·g-1,106.39±150.24ng·g-1, respectively) weresignificantly lower than residents eating local rices (1575.15±3501.12ng·g-1,253.98±282.26ng·g-1,respectively); THg in hairs of workers who works in mercury lamps factories were higher than workersof other kinds, with significantly difference in MeHg. In conclusion, the production of fluorescent lampsresulted in the elevation of mercury in rices and exposure to local residents. The assessment of mercuryexposure in these district indicated that the edible rice were polluted, but the threat to human healthywas in less-dangerous, longterm assessment and strictly assessment for further influence are required. |
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