宁波市东部地区大气中有机氯污染物的时空分布和污染特征

为了解宁波市不同功能区大气中有机氯污染物(Organochlorine pollutants, OCs)浓度水平、时空分布特征及其潜在来源,于2014年10月31日至2015年10月30日,运用聚氨酯泡沫(Polyurethane foam, PUF)被动采样器的方法,分析了宁波市大气OCs的主要来源。结果表明,宁波市大气中主要的农药为六六六(HCHs)、阿特拉津(Atrazine)、滴滴涕(DDTs)、硫丹(Endosulfans)和百菌清(Chlorothalonil),其平均浓度分别为4500、280、210、160 pg·m-3和87 pg·m-3。大气OCs浓度空间分布差异明显,浓度最高的地区是城市绿化区和茶园,其次为花卉种植区,最低的是滨海地区。OCs的污染特征表明,宁波市部分地区存在DDT和硫丹的使用,滨海地区三氯杀螨醇的使用对该地区大气DDT含量有较为明显的贡献。OCs浓度与温度的相关性研究表明,茶园和花卉种植区冬季受到阿特拉津、百菌清和硫丹等当前使用农药的影响。

Pollution characteristics and spatial-temporal variation of organochlorine pollutants(OCs)in eastern areas of Ningbo City, China

In order to explore the concentration, spatial-temporal variation and its potential sources of organochlorine pollutants (OCs), polyurethane foam (PUF) passive air samplers were deployed in different functional areas in Ningbo from October 31, 2014 to October 30, 2015. The predominant congeners were DDTs, endosulfans, HCHs, atrazine, and chlorothalonil with mean concentration of 210, 160, 4500, 280 pg·m^-3 and 87 pg·m^-3 respectively. The highest concentration of OCs were observed in urban greening areas and tea plantation area, while the lowest were coastal area and flower plantation area. The concentration of OCs in different agricultural area had different spatial characteristics. Pollution characteristics indicated fresh input of DDTs and endosulfans. Additional, high values of o,p'' -DDT and o,p''-DDT/p,p''-DDT in coastal area suggested the usage of dicofol. The correlation between the atmoshperic concentration of OCs and the temperature showed that the tea plantation and flower planting area was affected by atrazine, chlorothalonil and endosulfans.