摘要
基于2020~2022年望都县采暖季的观测数据,评估了PM_(2.5)中重金属的来源、源特异性金属及其健康风险等方面的年际变化,旨在评估“煤改气”对农村地区大气质量的影响.“煤改气”持续发挥正面作用,PM_(2.5)及其16种重金属(Cr、Pb、Tl、Ba、Sb、Sn、Cd、Sr、As、Zn、Cu、Ni、Co、Fe、Mn和V)的浓度均呈下降趋势,年均分别下降30.4%和43.4%.利用正定矩阵因子(PMF)模型解析重金属来源,燃煤(CC)贡献年均下降11.8%,而生物质燃烧(BB)逐年上升,并一跃成为2022年冬季的最大贡献源(33.7%),农村天然气短缺和供暖成本增加成为主要诱因.CC标识元素As和Pb浓度年均减少20.7%和48.5%,CC对其贡献率年均下降15.6%和13.5%.相应地,BB标识元素K的浓度和贡献率分别年均增长20.6%和7.4%.工业排放(IE)、交通排放(VE)和扬尘(FD)均呈现逐年上升的趋势.健康风险评估结果显示,单一元素仅有As和Cr致癌风险超过阈值,且As和Cr来源于CC和IE,因此,CC和IE被识别为致癌风险的主要来源.单一元素均未超过非致癌风险的阈值,但总风险在2020~2022年致癌风险持续存在.具体来讲,儿童存在的总致癌风险为64%,远远高于成人的36%,成人仅在2020年存在非致癌风险,而儿童始终面临非致癌风险.As作为致癌风险和非致癌风险的主要贡献者,由于煤炭燃烧对As排放的年均贡献大幅下降了15.6%,使得致癌风险和非致癌风险呈现出逐年下降的趋势.
This study evaluated the interannual variations in the sources,source-specific metals,and health risks of PM_(2.5)-bound heavy metals(HMs)based on observational data in heating seasons from 2020 to 2022 in Wangdu County,aiming to assess the impact of“coal-to-gas”(CTG)policy on air quality at rural areas.The CTG policy continued to play a positive role,both PM_(2.5)and 16HMs(Cr,Pb,Tl,Ba,Sb,Sn,Cd,Sr,As,Zn,Cu,Ni,Co,Fe,Mn,and V)showed a declining trend year by year with annual average reductions of 30.4%and 43.4%,respectively.Positive Matrix Factorization(PMF)model was used to analyze the sources of HMs and results indicated that the contribution of coal combustion(CC)decreased by an average of 11.8%annually.However,biomass burning(BB)increased year by year and leaped the largest contributor(33.7%)in the winter 2022,primarily driving by natural gas shortages and heating cost rises at rural areas.The concentrations of CC marker elements As and Pb decreased by 20.7%and 48.5%annually,and CC fractions declined by 15.6%and 13.5%per year,respectively.Similarly,the concentrations and fractions of BB marker element K increased by 20.6%and 7.4%annually.Industrial emissions(IE),vehicle emissions(VE),and fugitive dust(FD)all exhibited upward trends over the years.For health risk assessment:only As and Cr surpassed threshold of carcinogenic risks,and there were derived from CC and IE,therefore,CC and IE were identified as the main contributors to carcinogenic risks.However,individual elements did not exceed the threshold of non-carcinogenic risks,but the total carcinogenic risks persisted from 2020 to 2022.Specially,the total carcinogenic risks for children were 64%,which was much higher than 36%for adults.Together,adults only have non-carcinogenic risks in 2020,while children were always faced with non-carcinogenic risks.As a main contributor to both carcinogenic and non-carcinogenic risks for As,since the annual average contribution of CC to As emissions has dropped significantly by 15.6%,resulting in a year by year decline for carcinogenic and non-carcinogenic risks.
作者
马肖华
李志勇
朱语哲
邵梓涵
方昱顺
苗玉玲
刘晨
任壮壮
陈岚
韩斌
田宝娟
马会春
王佳琦
MA Xiao-hua;LIZhi-yong;ZHU Yu-zhe;SHAO Zi-han;FANG Yu-shun;MIAO Yu-ling;LIU Chen;REN Zhuang-zhuang;CHEN Lan;HAN Bin;TIAN Bao-juan;MA Hui-chun;WANG Jia-qi(North China Electric Power University(Baoding),Department of Environmental Science and Engineering,Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control,Baoding 071003,China;North China Electric Power University,College of Environmental Science and Engineering,Ministry of Edocation Key Laboratory of Resources and Environmental Systems Optimization,Beijing 102206,China;State Key Laboratory of Environmental Criteria and Risk Assessment,Chinese Research Academy of Environmental Sciences,Beijing 100012,China;Hebei Key Lab of Mineral Resources and Ecological Environmental Monitoring,Baoding 071051,China;China Environmental United Certification Center Co.,Ltd,Beijing 100029,China)
出处
《中国环境科学》
北大核心
2025年第8期4216-4224,共9页
China Environmental Science
基金
国家自然科学基金资助项目(41830965)
北京市自然科学基金资助项目(8212034)
河北省自然科学基金资助项目(B2023502013)
河北省矿产资源与生态环境监测重点实验室开放基金项目(HBMREEM202307)。
