Health Risk Assessment Of Rural Solid Waste Based On 3MRA Model

The economy of Chinese rural area developed rapidly after the reform and opening up, and the industrial structure was becoming more and more diverse especially for the agriculture, industrial and mining industry in rural area. However, accompanying with the development, solid wastes were also more diverse, which aggravated environmental pollution in rural areas. Organochlorine pesticides are persistent organic pollutants and have a long history of application in China. Some rural areas still used this type of pesticide and packaging wastes were arbitrarily discarded resulting in rural environmental pollution. In addition, because of lack of supervision, some industrial solid wastes were stored in rural area, which further aggravated environmental pollution in rural areas.Contaminants would transformed in environmental media, and the concentration of them would increased gradually by the food chain. Human beings were on the top of the food chain therefore we had higher risk in pesticides and heavy metal pollutanted environment. Based on this, health risk assessment of rural solid waste in eight villages around China was carried out based on 3MRA model. And the health risk in waste pile and landfill model and safe concentration in landfill model of chlorobenzene, pentachlorophenol, methoxychlor,2,4-dichlorophenoxyacetic acid, As, Cr6+ and Pb were predicted, respectively. The results showed that the healthy risk of pesticide contaminats in wastes in 8 villages was in 10-6 level, of heavy metal was in I07 level. And landfill was effective to decreasing the health risk of rural solid waste. Affected by the types of waste in the village, climate characteristics, crop types and so on, high risk exposure ways between 8 villages were also different. Air exposure was the high risk for pesticide contaminats, and sufurwater, groundwater and crop exposure were high risk for heavy metal contaminants. Scenarios conditions had a significant effect on safe concentration of contaminants, and they should be adjusted according to the actual situations.Based on these results we proposed that recycling box for waste battery and pesticide bottle should be placed in villages to decrease the health risk of heavy metals and pesticides, and that some solid wastes were able to be landfill if the concentration of comtaminants was lower than the safe concentration in high rainfall area. But for the area where groundwater was low and used production and living, we suggested that the solid wastes should be collected to manage to decrease their healthy risk for human benings around them.