依据2009年7月至2012年2月连续3年对杭州城区环境空气中二噁英(PCDD/Fs)采样分析结果得知,杭州城区环境空气中二噁英毒性当量质量浓度变化范围为0.13~0.55 pg TEQ/m~3,均值为0.34 pg TEQ/m~3。城区环境空气中二噁英浓度季节变化不显著,夏季略低于冬季;城区范围内不同功能区之间二噁英浓度差别不显著;连续3年监测结果未显现二噁英年度变化趋势。沙尘暴天气环境空气中二噁英浓度显著增高,日常天气和烟花爆竹集中燃放天气环境空气中二噁英形态分布存在明显区别,烟花爆竹集中燃放期间八氯代二苯并-对-二噁英(OCDD)占总质量浓度比例显著提高。利用IBM SPSS Statistics 19.0统计软件对24个监测结果聚类分析发现,杭州城区环境空气中二噁英的同类物分布具有明显的"源"分布特征。
According to the result of PCDD/Fs of the ambient air of Hangzhou city from July 2009 to February 2012, PCDD/Fs toxic equivalent concentrations range from 0. 13 to 0.55 pg TEQ/m3 and the average value is O. 34 pg TEQ/m3. It is manifested that the PCDD/Fs concentrations of the ambient air of Hangzhou city rarely change with seasons; the values in summer were slightly lower than those in winter; There were no significant changes among main administrative areas; annual trend was not found during 2009 to 2012; the PCDD/Fs concentrations increased significantly in sandstorm weather. The dioxin homulogues distributions in ambient air of fireworks heavily setting off weather and normal weather were significantly different, The proportion of total mass concentration of OCDD was significantly increased Analyzing the 24 monitoring results by using software of IBM Statistics 19.0, it is manifested that distribution of PCDD/Fs congeners in the ambient air of Hangzhou city has significant source characteristics.