Pollution Levles And Health Risks Of Chlorinated Paraffins And Polycyclic Aromatic Hydrocarbons In Typical Areas

Chlorinated paraffins(CPs)are a group of synthetic chlorinated n-alkanes.Given the persistence,long-term transportation,high toxicity,and bioaccumulation,short-chain chlorinated paraffins(SCCPs)are listed as a new Persistent Organic Pollutant(POPs).Medium-chain chlorinated paraffins(MCCPs)also proved to be persistent and toxic to the biota.Therefore,high concerns are paid to SCCPs and MCCPs in the global environment.Polycyclic aromatic hydrocarbons(PAHs)are a group of unintentional produced aromatic hydrocarbons.They mainly originated from incomplete combustion of gas,coal,and fossil and are one of the ubiquitous organic pollutants in the air.In this thesis,the levels,temporal and spatial distribution,seasonal trends and potential health risk of SCCPs,MCCPs,and PAHs in typical industrial park surroundings and nearby city and developed area Yangtze river delta were investigated.This study was suppoted by the Chinese National 973 program named regional characteristics,environmental risk and control theory of new POPs and China-Canada cooperation program named National Construction of High-Level Postgraduate Program.A new method to determine SCCPs and MCCPs in the environment using comprehensive two-dimensional gas chromatography with electronic capture negative ionization coupled with low-resolution mass spectrometry(GCxGC-ECNI-LRMS)was developed as well as the pretreatment.Two columns coupled together in GC ×GC significantly improved the separation of SCCP and MCCP congeners.When the rate of the oven program was 1.5?/min,hot jet time was 300 ms and the modem time was 10 s,the complete separation of SCCPs and MCCPs was achieved which is essential for the quantification with LRMS.Selected ion monitoring(SIM)mode was used in this LRMS method.[M-Cl]-ions were chosen as quantitive ions and[M-HCl]-was chosen as qualitative ions.The calibration curve was established between the total relative respond factor and the chlorine content,which could remove the instrumental respond influence of different chlorine contents.SCCP and MCCP studies were conducted in a chlorinated paraffin industrial park surroundings and nearby city Zhengzhou to investigate the influence of the production and usage of commercial CP productions in the environment.Concentrations of SCCPs ranged from 114 to 839 ng/g dw and from 355 to 530 ng/g dw respectively,in tree barks and pine needles in CP plants surroundings and concentrations of MCCPs ranged from 161 to 908 ng/g dw and from 161 to 317 ng/g dw respectively,in tree barks and pine needles in CP plants surroundings.In Zhengzhou area,SCCP concentrations ranged from 125 to 1200 ng/g dw and from 217 to 1290 ng/g respectively,in tree barks and pine needles and MCCP concentrations were from 103 to 1010 ng/g dw and from 147 to 815 ng/g dw respectively,in tree barks and pine needle samples.Lower CP concentrations were found in CP plants surroundings(1 km away or further)than in the Zhengzhou city area as well as Beijing urban area in China,which proves the pollution of CP plants to the air(1 km or further)is less severe than the pollution of CP usage in the city region.In most samples,C10 congeners were the dominated groups in the total SCCP concentration,followed by C11 group.The most abundant group of MCCPs in tree bark and needle samples was C14,with the average accounting for approximately 48.7%of the total MCCP concentrations,followed by C15(21.6%),C16(17.5%),and C17(12.2%).Shorter carbon chain of SCCPs and MCCPs are more volatile than longer carbon chain SCCPs and MCCPs,which makes shorter carbon chain congeners could transport further.Maybe this is the main reason that C10 and C11 groups are the main groups of SCCPs and C14 group is the main group of MCCPs.Cl7 and Clg chlorine groups were the major contributors of SCCPs and MCCPs in all the samples.To investigate the potential sources of SCCPs and MCCPs in CP industrial park surrounding regions and Zhengzhou city,principal component analysis(PCA)was executed in this thesis.The results suggested that 24 SCCP congeners and 24 MCCP congeners in tree bark samples originated from different sources.The European Union System for the Evaluation of Substance(EUSES 2.0)used in this thesis tracks the human health risk of SCCPs and MCCPs.The results showed that no significant risk was found through one pathway,however both local total daily intakes of SCCPs and MCCPs(53.1?g/kg/d and 123 ?g/kg/d,respectively)exceeded the tolerable daily intake(TDI,10 ?g/kg/d)given by Health Canada,suggesting that the residents in that area were confronted with high health risk from CPs.Concentrations,spatial distribution,seasonal trends,and potential health risk were investigated in the developed Yangtze River Delta(YRD)area.The atmospheric concentrations of SCCPs in YRD ranged from 4.05 ng/m3 to 42.2 ng/m3 and the 15 PAH concentrations ranged from 6.48 ng/m3 to 154 ng/m3.Compared to other SCCP studies in China,levels of SCCPs in the air in YRD are relatively low,however,the levels are higher than other global studies(such as the United Kingdom,Canada,and Norway).The concentrations of PAHs in YRD are in the middle-level compared to other global PAHs studied in the air.The highest concentration of SCCPs was found in the rural-urban transition area and urban area,and the highest concentration of PAHs was found in the urban area.The atmospheric concentrations of SCCPs were higher in summer than in winter and C10 and C11 groups were the main groups of SCCPs and Cl6-7 groups were the dominant groups of SCCPs.The highest level of PAHs in the air was in Autumn,followed by winter and spring,and the lowest level of PAHs was in summer.Compared to other atmospheric organic pollutants in YRD,the highest concentration was PAHs,followed by SCCPs,OCPs,PCBs,and the lowest concentration was PBDEs.The profiles of atmospheric SCCP congeners were similar with the profiles of the commercial chlorinated paraffin(CP)42 and 52.Therefore,the source of the SCCPs in YRD may be the usage of the commercial production of CP 42 and CP 52.For the potential source of PAHs,PCA and relationship between Flt/(Flt+Pyr)and Ant/(Ant+Phe)and between IP/(IP+BghiP)and Ant/(Ant+Phe)were used to in this thesis.The results showed that PAHs were originated from vehicle emission and coal/biomass incompleted combustion.In addition,the daily exposure of SCCPs to the children and adults through air inhalation were lower than the TDI value of World Health Organization(WHO,100 ?g/kg/d),but the 95%exposure TDI of children was higher than the TDI value of Health Canada(10 ?g/kg/d),suggesting that the residents in YRD may confronted with a certain extend health risk from SCCPs.According to the toxic equivalent index(TEI)from the United States Environmental Protection Agency(USEPA),the toxic equivalent quivalents(TEQs)of BaP and BbF were calculated.The TEQs surpassed the the dibenzo-p-dioxins(PCDDs)and polychlorinated dibenzofurans(PCDFs)emission standard of the Chinese pollution control for hazardous waste incineration and were more than thousands of times that of Japanese dioxin ambient air quality standard.Although,the toxicity of the PAHs was lower than the PCDDs and PCDFs,limited PAHs air quality standard were found.As a reference,the high values of PAHs' TEQ,which grossly exceeded the limits of dioxin ambient air quality standard,indicated potential health risks to humans.Concentrations,spatial distribution,seasonal trends,and potential health risk were investigated in the Toronto city in Canada.The atmospheric concentrations of SCCPs in Toronto ranged from 4.13 ng/m3 to 84.9 ng/m3,with the average value 23.0 ng/m3.The levels are comparable to the SCCP levels in YRD(from 4.05 ng/m3 to 42.2 ng/m3)in this study,a little higher than the levels in South Korea and Japan,but much lower than the levels in Dalian and Beijing in China.In general,C10?C11?C12 and C13 contributed equally to the total SCCPs,with 23.5±8.67%?23.3±4.19%,28.0±4.96%and 25.2±8.12%,respectively.C12 and C13 groups were higher than the other two groups in traffic sites and industrial sites,with the contribution of 30.7%and 28.0%,respectively.Four carbon groups were equal to the total SCCP concentrations in the residential and urban sites.Regarding the chlorine content,C15,C17 and C16 were the dominant groups.The concentrations of atmospheric SCCPs in Toronto didn't show an obvious difference between seasons.The highest level was in autumn,followed by winter,spring,and the lowest level was in summer.In addition,the daily exposure of SCCPs to the children and adults through air inhalation were lower than the TDI value of World Health Organization(WHO,100 ?g/kg/d),but a little higher than the TDI value of Health Canada(10 ?g/kg/d),suggesting that the residents in Toronto might confronted with a certain extend of health risk from SCCPs.