2018~2019年冬季天津和青岛PM_(2.5)中重金属污染特征与健康风险评价

Pollution Characteristics and Health Risk Assessment of PM_(2.5) Heavy Metals in Tianjin and Qingdao in Winter of 2018-2019

于2018年12月18日至2019年1月22日在天津和青岛进行PM_(2.5)样品采集,利用电感耦合等离子体质谱仪(ICP-MS)测定PM_(2.5)中18种元素(Na、Mg、Al、K、Ca、V、Cr、Mn、Fe、Ni、Cu、Zn、As、Se、Mo、Cd、Ba和Pb)浓度,运用富集因子法讨论了元素的富集程度,并评估了重金属的生态风险和健康风险.结果表明,采样期间天津和青岛ρ(PM_(2.5))平均值分别为(93.6±53.5)μg·m^(-3)和(85.5±60.3)μg·m^(-3);Zn是PM_(2.5)中最主要的微量元素;富集因子结果表明,Se、Cd、Zn、Pb、Mo、Cu和As元素富集程度高,污染严重,主要受人为活动的影响.在天津重金属的潜在生态风险大小依次为:Cd>Mo>Se>Pb>As>Cu>Zn>Ni>Cr>V,在青岛重金属的潜在生态风险大小依次为:Cd>Se>Mo>As>Pb>Zn>Cu>Ni>Cr>V,Cd元素的贡献最大,对天津和青岛生态风险的贡献率分别为67%和86%,属于极高的风险等级.健康风险评价显示,手口摄入是引起非致癌风险和致癌风险的主要暴露途径,且儿童非致癌风险和致癌风险均高于成人,天津和青岛的重金属对儿童的综合非致癌风险(HI)值分别为5.38和5.40,对成人的HI值分别为1.04和1.02,均高于1,说明成人和儿童均存在明显的非致癌风险,且以As和Pb的非致癌风险最大.重金属致癌风险(CR)值大小依次为:As>Cr>Pb,其中As在天津和青岛的儿童中存在致癌风险,Cr和Pb存在潜在致癌风险.

PM_(2.5) filter samples were collected in Tianjin and Qingdao from December 18,2018 to January 22,2019.The mass concentrations of 18 elements(Na,Mg,Al,K,Ca,V,Cr,Mn,Fe,Ni,Cu,Zn,As,Se,Mo,Cd,Ba,and Pb)were determined using inductively coupled plasma mass spectrometry(ICP-MS).The enrichment factor was used to discuss the enrichment degree in PM_(2.5).The ecological risk and health risk of heavy metals in PM_(2.5) were evaluated.The results showed that the average concentrations of PM_(2.5) in Tianjin and Qingdao were(93.6±53.5)μg·m^(-3) and(85.5±60.3)μg·m^(-3),respectively.Zn had the highest concentration among the trace elements.The enrichment factor results showed that the Se,Cd,Zn,Pb,Mo,Cu,and As elements were highly enriched and polluted,which were mainly affected by anthropogenic activities.The potential ecological risk indexes of heavy metals in Tianjin were as follows:Cd>Mo>Se>Pb>As>Cu>Zn>Ni>Cr>V;in Qingdao,the order was Cd>Se>Mo>As>Pb>Zn>Cu>Ni>Cr>V.Cd contributed most to the ecological risk,with 67%and 86%,respectively,in Tianjin and Qingdao,indicating an extremely strong risk level.The health risk assessment showed that oral and manual ingestion was the main exposure route causing non-carcinogenic and carcinogenic risks,and both the non-carcinogenic and carcinogenic risks in children were higher than those in adults.The comprehensive non-carcinogenic risk(HI)values of heavy metals in Tianjin and Qingdao were 5.38 and 5.40 for children and 1.04 and 1.02 for adults,with both higher than 1.This indicated that both adults and children had obvious non-carcinogenic risks,and As and Pb posed the highest non-carcinogenic risks.The order of carcinogenic risk(CR)of heavy metals was As>Cr>Pb.As posed carcinogenic risk in children in Tianjin and Qingdao,and Cr and Pb had potential carcinogenic risk.