| Objective:Since the reform and opening-up,China has experienced an rapid development on economy and industrialism.While along with the achievements of the last decades,there have emerged several challenges in ecological environment.At present,China’s environmental situation remains grim and the health damage caused by the different pollutants has attracted extensive attention.Under the background of global economic integration,chemical companies in China tend to develop intensively.On the one hand,it can promote the standardized development of chemical enterprises,and on the other hand,it also brings huge pressure and threat to local environment.Under this circumstance,it is urgent to carry out monitoring on the pollution in chemical industry park,to protect the health of the local residents.Volatile organic compounds（VOCs）are the main types of pollutants in chemical industry parks,which have character of low boiling points,and are easy to volatilize into the air to further affect human health in inhalable ways.The aim of this study was to investigate the exposure and health risk of VOCs from both macro and micro perspectives.On the one hand,we aimed to investigated the status of volatile organic pollutants in chemical industry parks to clarify the level of environmental pollution,external exposure level and individual internal exposure level,as well as to assess the population health risks;On the other hand,we further aimed to study the hepatotoxic effects of volatile organic compounds exposure,to provide technical support for environmental management and population protection policy.Methods:The first part is the epidemiology survey on ambient VOCs exposure and external and internal exposure,as well as the evaluation of health risk.Main methods are as the follows:（1）The Jilin Petrochemical Production industrial park and the surrounding residential areas were selected as the environmental survey scope of this survey area,and Jiangnan Park,which is located in Fengman District,Jilin City was selected as a control area.The ambient air was used as the monitoring medium and the on-site measured survey method was used to collect the gaseous pollutants in the ambient air of the survey area.The monitoring time is August 2016（summer）and December 2017（winter）.Monitoring projects include benzene,toluene,ethylbenzene,p-xylene,mxylene,o-xylene,chloroform,carbon tetrachloride,trichloroethylene,tetrachloroethylene,tribromomethane,monobromodichloromethane,and dibromo Methyl chloride.（2）In the external exposure survey area,the grid method was adopted to select the residential household as the external exposure survey point,15 households on the third floor in the survey area and the control area are selected for indoor air monitoring.The monitoring point is located in the living room.The height of the point sampling is the same as the height of the human breathing zone,and the relative height is between 0.5 and 1.5 m.The monitoring time of the external exposure survey is consistent with the environmental survey monitoring time,also in August 2016（summer）and December 2017（winter）.Monitoring projects include benzene,toluene,ethylbenzene,p-xylene,m-xylene,o-xylene,chloroform,carbon tetrachloride,trichloroethylene,tetrachloroethylene,tribromomethane,monobromodichloromethane,and dibromo Methyl chloride.（3）In the Jilin Petrochemical and surrounding areas,we select the perennial dominant wind downwind direction residential area as the survey area of human health survey and select Jiangnan Park in Fengman District of Jilin City as the control area.787 residents in the survey area and 939 residents in the control area were selected for questionnaires and health surveys.Among them,238 residents in the survey area and 261 people in the control area were selected to collect blood sample and test the level of benzene and halogenated hydrocarbons.（4）By applying classical environmental health risk assessment model,we evaluated the carcinogenic risk and non-carcinogenic risk considering the inhalation exposure path.The second part is toxicology experiment to test the hepatotoxicity of VOCs.A rat model of benzene,toluene,and chloroform combined with toxicological exposure was established.The exposure concentration of pollutants was set to 3 gradients.The daily exposures of benzene,toluene,and chloroform in the low dose group were 0.21 mg/kg,1.05 mg/kg and 0.11 mg/kg,respectively.The concentrations were 10 times and 100 times of low-dose group respectively,as a middle-dose group and high-dose group.At the same time,the control group,the anesthesia control group and the solvent control group were set,and the inoculation was inoculated once every 3 weather tubes for 30 days.Results:For the epidemiology survey study,we obtained four main results as follows.（1）Ambient VOCs exposureThe survey showed that the average concentration of benzene and halogenated hydrocarbons of the ambient in the survey area was higher than that from the control area,in both summer and winter,and the average concentration did not exceed the relevant standards.（2）external exposureThe survey showed that the average concentration of benzene and halogenated hydrocarbons in the indoor air in survey area was higher than that in the control area,in both summer and winter,and the average concentration did not exceed the relevant standards.（3）internal exposureThe results showed that the detection rate of o-xylene in the blood of residents in the survey area was higher than that of the residents in the control area.The blood levels of o-xylene,chloroform,trichloroethylene,tribromomethane and monobromodichloromethane in the residents of the survey area were higher than those from the control area.The benzene series and halogenated hydrocarbons in the blood have a certain relationship with the blood,urinary routine,liver and kidney function and oxidative stress,which may affect human health.However,some results of the biology index level were inconsistent with the findings above.（4）Health risk assessmentThe carcinogenic risk of benzene series and halogenated hydrocarbons in people from the exposed area was higher than that from the control area,in which the total carcinogenic risk of benzene and ethylbenzene was 5.93×10-5;The total carcinogenic risk is 4.75×10-5,both were higher than 1×10-6.For the toxicical experiment study,we observed the following main result.We found that the exposed body weight,partial organ weight and organ coefficient of rats were decreased in rats from the study group.The pathological sections of the liver tissue of rats in the high dose group were abnormal,and the liver function index was abnormal,indicating liver damage.Conclusions:（1）The average concentration of benzene series and halogenated hydrocarbon in summer and winter was higher than that in the control area.The average concentration of benzene series and halogenated hydrocarbon in the indoor air of the investigated residents were higher than that in the control area.（2）The detection rate of o-xylene in the blood of residents in the survey area was higher than that of residents in the control area,while the detection rate of trichloromethane,trichloroethylene,tribromomethane and monobromodichloromethane in residents in the control area was higher than that of residents in the survey area.The blood levels of o-xylene,trichloromethane,trichloroethylene,tribromomethane and monochlorohydrin in residents in the survey area were higher than those in residents in the control area.Benzene series and halogenated hydrocarbon in blood were found related to blood routine,urine routine,liver and kidney function and oxidative stress,which may affect human health.（3）The concentration of benzene series and halogenated hydrocarbon in the exposure path of pollution source environmental quality external exposure internal exposure,only the external exposure of bromodichloromethane was related to the internal exposure concentration,which may be related to the rapid degradation of organic matter in vivo.The indoor air pollution is related to the blood routine,urine routine,liver and kidney function and oxidative stress.（4）The carcinogenic risk of benzene series and halogenated hydrocarbon in indoor and outdoor air of exposure area was higher than that of control area.（5）The rats exposed to VOCs can reduce their body weight,cause damage to tissues and organs,especially the liver and spleen,cause inflammatory changes in the liver,reduce the ability of scavenging oxygen free radicals and reduce the ability of antioxidation.（6）After exposure to VOCs,the content of Microelements in liver tissue of rats decreased,and the change of microelements was closely related to the metabolism in liver,which would cause the disorder of liver metabolism. |
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