某化工企业周边土壤中二噁英污染水平及其分布特征研究

Pollution Levels and Distribution Characteristics of PCDD/Fs in Soil Around a Chemical Company

应用高分辨气相色谱/高分辨质谱(HRGC/HRMS)对某化工企业周边土壤中的二噁英(PCDD/Fs)含量、分布特征及来源进行研究。结果表明:所有土壤点位中PCDD/Fs单体平均质量分数为109 pg/g,毒性当量平均质量分数为10.1 pg/g,居民区的土壤受到污染程度较厂内的小。PCDD/Fs同系物主要以单体OCDD和OCDF为主,分别占比18.5%,11.4%,废气中PCDD/Fs同系物也以OCDD和OCDF为主,分别占比16.2%,10.1%;60%点位同族物以H_6CDFs贡献最大,30%点位同族物以OCDD贡献最大,废气中同族物也以H_6CDFs和OCDD为主,分别占比22.9%,16.2%。对研究区域土壤中PCDD/Fs的含量、分布特征及来源分析表明,土壤中PCDD/Fs主要来源于该化工企业废弃物焚烧炉排放。

The content,distribution characteristics and source of PCDD/Fs in soil around a chemical company were analyzed by high resolution gas chromatography(HRGC)/high resolution mass spectroscopy(HRMS).The results showed that the average value of total concentrations of PCDD/Fs congener in soil was 109 pg/g.The average value of toxic equivalent was 10.1 pg/g.The congener of PCDD/Fs was dominated by OCDD and OCDF in soil,accounting for 18.5%and 11.4 respectively,the main congener of PCDD/Fs in waste gas was also OCDD and OCDF,accounting for 16.2%and 10.1%.The larger contribution of PCDD/Fs homolog in 60%soil point was H6CDFs,in 30%soil point was OCDD,the main homolog of PCDD/Fs in waste gas was also H6CDFs and OCDD,accounting for 22.9%and 16.2%.The analysis of PCDD/Fs content,distribution characteristics and source in soil of the study area showed that the major source of PCDD/Fs in this area was from the flue gas emissions.