Health Risks Of Municipal Solid Waste Harmless Disposal

Along with polulation growth,fast urbanization and economic booming,the amount of municipal solid waste(MSW)is also growing rapidly in China.Incineration and landfill are two major ways of MSW harmless disposal in China.Both disposal techniques can emit vrious types of pollutants causing negative impacts on environment,social life and human health.Pollutants such as heavy metals and dioxins emitted from incinerators can lead to chronic health effects such as carcinogenesis and teratogenesis and acute respiratory health effects such as cough and pneumonia,through inhalation and other exposure ways.Malodorous gases and carcinogens emitted from landfills also have enormous impacts on humans,increasing the health risks of blood diseases and cancer.As a potential way to solve the problem of "garbage besieged city"and resol eve the shortage of land resources,MSW incineration has been encourged by government through issuing a series of guiding documents.However,incineration development in China has stimulated numerous "not in my backyard" issues,which hampers the implementation of government policies.This dilemma partly results from the lacks of scientific evidence comparing health risk of MSW incineration and landfill.In order to alleviate the policy resistance coming from the society,it is fundamental to carry out a comparative study between the health risks of MSW incineration and landfillIn this context,our study established the historical MSW incineration and landfill emission inventories.Using the Gaussian Diffusion Model,the Risk Quotients Model and the distribution of population data,we characterized the spatial and temporal distributions of health risks caused by MSW incineration and landfill through inhalation We then compared the relative health risk between MSW incineration and landfill Meanwhile,we desinged seven possible MSW incineration development scenarios to predict future health risks in 2035.Factors were considered for example population growth and distributions,waste classification and recycling,ratio of incineration,and technology development etc.The scenarios include:Baseline Scenario(BAU),Change of Incinerator Scenario(CI),Technology Improvement Scenario(TI),Classification and Recycling Scenario(CR),Incineration Ratio Improvement Scenario(IRI),Comprehensive Scenario 1(CS1),and Comprehensive Scenario 2(CS2).Then we predicted the amount and the distribution of MSW combing MSW amount per capita,ratio of incineration,fitness ranking for site selection of MSW incineration and population density.We also predicted the health risk level of MSW harmless disposal in 2035 combining the Gaussian Diffusion Model and the Risk Quotients ModelThe result shows that non-carcinogenic risk caused by MSW incineration was lower than landfill,and both of them were lower than the maximum acceptable level of EPA(HI?1).From 2015 to 2017,carcinogenic risks caused by landfill were 9.42 × 10-6,9.40 × 10-6,9.37 × 10-6,respectively,which were about nine times of the maximum acceptable level(CR?1 × 10-6).Carcinogenic risks caused by incineration were 5.71× 10-6,7.92 × 10-6,9.44 × 10-6,from 2015 to 2017,which were five to nine times of the maximum acceptable level.Furthermore,health risks caused by MSW harmless disposal had strong spatial heterogeneity,Beijing,Shanghai,Jiangsu,Zhejiang,Tianjin and Guangdong were at high landfill carcinogenic risk level.In recent years,the impacted area of incineration has been continuously expanded and the impacted degree has been increasing,risky areas are mainly located in Jing-jin-ji region,Yangtze River Delta,and eastern and southeast coastal areas.Besides,the relative risk of incineration and landfill is heterogeneous at provincial level.Average and per unit waste carcinogenic risks of landfill were higher than incineration' s in Shanghai,Shaanxi and other provinces,while average and per unit waste carcinogenic risks of incineration were higher than landfill' s in Guangdong and other provincesIn terms of health risks of incineration in the future,non-carcinogenic risks of different scenarios are lower than the maximum acceptable level.Carcinogenic risks are:BAU(2.10 × 10-5),CI(1.28 × 10-6),TI(6.83 × 10-7),CR(1.60 × 10-5),IRI(3.39 ×10-5),CS1(1.71 × 10-5),CS2(5.57 × 10-7).It shows that if we only increase the proportion of incineration without any measures to mitigage risks,the carcinogenic risk of MSW incineration will be 3.6 times that of 2017.Health risk of Classification and Recycling Scenario(CR),Change of Incinerator Scenario(CI),and Technology Improvement Scenario(TI)will decrease by 24%,94%and 97%,respectively,compared to Baseline Scenario(BAU).Only relying on incineration change and waste classification and recycling can not effectively control the risk of MSW incineration,but can counterbalance the increased risk level caused by the increased proportion of incineration.Technology progress is the most effective way for controlling the emission of pollutants and the health risk level of incineration,which can reduce health risks by more than 90%and make sure health risks are lower than the maximum acceptable level The MSW incineration will be sustainable by improving the classification and recycling rate of waste,adopting advanced incinerator types,and promoting advanced incineration technology and pollutant emission control technologyThe research shows that health risks caused by MSW incineration can not be ignored.But incineration is a relatively low-risk alternative method compared to landfill.Incineration with strong capacity and small footprint can solve problems of"garbage besieged city",and "not in my backyard" issues.Pollutant emissions and social resistance can be solved by optimizing site selection of incineration plants,accelerating the construction of the waste classification and recycling system,choosing advanced incinerator types,increasing the promotion rate of advanced incineration technology and pollutant control technology,and enhancing information disclosure and risk communication,so that incineration development can meet the overall development plan of the city,guarantee the safety of the environment and the health of the residents,and achieve the sustainable development in terms of resources,environment,and health risks.