Screening The Target Pollutants Of Atmospheric Health Benchmark And Studying On Toxic Components And Effect Of Airborne PM_2.5

At present,air pollution is becoming increasingly serious,as a result,air pollution and health problems have led to the attention of whole society.In order to control air pollution,developing an atmospheric health benchmark has become one of the effective measurements for environmental management.Meanwhile,establishing an atmospheric health benchmark requires a prioritization of atmospheric pollutants to obtain a list of target pollutants,and then carry out the benchmarking study on the target pollutants in the list.Currently,China's existing list of air pollutants mainly refer to the developed countries,the technology and method of atmospheric pollutant screening of our country has not yet established.For this purpose,in our work,a method for screening the target pollutants of air environment health benchmark was constructed,and a list of pollutants for atmospheric health benchmark in China was put forward based on it.Currently,China is experiencing atmospheric particulate matter pollution severely,and atmospheric particulates are closely related to many health diseases.Particulate matter in the atmosphere,especially PM_2.5,is a key member of the candidate list of environmental health targets,which has caused serious health problems and social problems.In order to better understand the health effects of PM_2.5we need to analyze the composition of PM_2.5,and study the relationship between PM_2.5 and health diseases and its mechanism.Therefore,we analyzed the element and organic composition of PM_2.5 samples collected from 2013 to 2015 in Beijing area.The effects of PM_2.5 on human lung epithelial cell line 16HBE and human vascular endothelial cell HUVEC were also studied.The research contents and results are summarized as follows:In this paper,a method of screening the target pollutants for atmospheric health benchmark was established by the detection rate score,toxicity effect score,population exposure score of pollutants.It was used to screen and present the candidate list of target pollutants for atmospheric health benchmark in China.The results showed that there were 38 kinds of pollutants into the initial pollutant candidate list,including conventional pollutants?heavy metal pollutants and atmospheric volatile organic compounds?VOCs??polycyclic aromatic hydrocarbons?dioxins and so on.The detection rate scores were between 0-600 points,where national routine monitoring of pollutants was the highest score.The toxicity effect scores were mostly between 300-500,with the highest scores being benzene?PM_2.5?PM₁₀?dioxins.The population exposure scores were between 10 and 100,with the highest score being CO?toluene?O₃?PM_2.5?PM₁₀?NO₂.15 kinds of pollutants scores were above 900 points in the health risk among the 38 kinds of pollutants,including 6kinds of conventional pollutants,2 kinds of major categories of pollutants,2 kinds of heavy metal pollutants,5 kinds of VOCs.Therefore,the 15 kinds of pollutants were listed as candidate target pollutants of China's atmospheric health benchmark.In this paper,the chemical composition of the PM_2.5 in the candidate list of the environmental health target was further studied.It is speculated that eight elements such as Na?Cu?Zn?Cr?Cd?Sb?Pb in the PM_2.5 samples might be from the anthropogenic sources.211 kinds of organic compounds,of which about 30%of the total number of carcinogenic polycyclic compounds,were measured.In this paper,the toxic effect of PM_2.5 was also studied.It was found that the cytotoxicity of PM_2.5 to 16HBE and HUVEC was obvious,and have a negative correlationship between concentration of PM_2.5.5 and cell survival rate.It was also found that PM_2.5 exposure could induce autophagy in HUVEC cells.The results showed that the promotion of autophagy increased the cell survival rate in HUVECs,while inhibition of autophagy decreased cell viability,suggested that autophagy induced by PM_2.5 exposure may be a self protective mechanism of cells.In addition,the NF-?B signaling pathway may be involved in the cytotoxicity of HUVECs induced by PM_2.5.5 exposure.