被动采样法研究闽南城市室内外空气中的多溴二苯醚

Polybrominated diphenyl ethers (PBDEs) are a class of new emerging persistent organic pollutants (POPs). Unlike polychlorinated biphenyls (PCBs) which were mainly ingested by human from food, indoor environments play a major role in the intake of PBDEs. Researches on the indoor PBDEs are in urgent need of strengthening as the available reports were mainly outdoors. Comparing with active sampling, Passive air samplers (PAS) are particularly suitable for indoor air pollutants sampling in developing countries because of cost-effective, simultaneous monitoring at multi-sites for several months and consequently with comparable results, no need for electricity and noise free operation. Unfortunately, the relevant researches are currently very scarce in China. This research takes Minnan city as an example, which was under rapid development of economic construction and urbanization progress, and where the urban district is small and densely populated. Passive air samplers were used to collect air samples in different seasons. Congener-specific sampling rates of PBDEs were calibrated by active air sampling. Concentrations, compositions, distribution characters, seasonal variations, major emission sources, human inhalation exposure and corresponding improvement measures of PBDEs in the indoor and outdoor air were investigated. The results of this research could be helpful to the application of PAS to the sampling of indoor air pollutants, and provide the scientific basis for urban indoor PBDEs researches on the pollution sources, profiles, seasonal variations and health risk assessments.

多溴二苯醚（PBDEs）是一类新的持久性有机污染物。近年研究发现，与多氯联苯等主要通过食物摄入不同，室内环境在人体对PBDEs的暴露中起主要作用。但现有报道主要集中于室外大气，对室内PBDEs的研究亟待加强。相比主动采样法，被动采样法具有成本低廉、便于多点同时长时间采样，无噪音、无需电源等特点而尤其适用于发展中国家室内空气污染物采样，而目前国内有关研究非常缺乏。本研究以经济建设和城市化进程迅速、地少人多、人口密集的闽南城市为例，用被动采样法采集不同季节的空气样品，并用主动采样技术校正得到基于PBDEs同系物的采样速率，研究城市室内外空气中PBDEs浓度、组成、分布特点、季节变化、主要释放源、呼吸暴露水平及相应的改善措施等，为被动采样技术用于室内环境空气污染物的采样监测积累有益经验，为研究城市室内环境中PBDEs的污染来源、特点、季节变化及健康风险评价等提供基础资料。

多溴二苯醚（PBDEs）是一类持久性有机污染物，室内环境在人体对PBDEs的暴露中起主要作用。本研究以闽南城市为例，用被动采样法采集四季空气样品，并用主动采样技术校正得到基于PBDEs同系物的采样速率，研究城市室内外空气中PBDEs的浓度、组成、分布、季节变化、主要释放源和呼吸暴露水平等。主要结果如下：1）Penta-、Octa-和Deca-BDE的室内年均被动采样速率分别为2.9、0.5和0.5 m3∙d-1，室外分别为7.5、4.2和4.7 m3∙d-1，采样速率有显著的季节变化。2）闽南城市室外空气中ΣPBDEs的年几何平均质量浓度为108.5 pg∙m-3（11.5～2124.4 pg∙m-3），其中，泉州最高（178.1 pg∙m-3），厦门次之（116.3 pg∙m-3），漳州（47.3 pg∙m-3）和龙岩（40.3 pg∙m-3）较低。工厂（1917.1 pg∙m-3）和电器卖场（211.5 pg∙m-3）年均值高于家庭（84.2 pg∙m-3）、办公室（73.5 pg∙m-3）和机房（61.7 pg∙m-3），PBDEs在生产和产品中仍有使用。与国内外相比，闽南城市室内外空气中PBDEs的污染程度较低。3）同系物组成上，室外空气BDE-209平均在95%以上，家庭、办公室、机房中BDE-209的比例低于室外且依次减小，但工厂、电器卖场则高于室外。4）Σ15PBDEs主要来自室内（I/O比>1），而BDE-209则多来自室外（I/O比≤1）。工业生产和添加PBDEs产品的使用是室内外空气中PBDEs的主要来源。室内Σ15PBDEs有显著的季节变化，而BDE-209则主要受到本地释放源的影响。5）闽南城市成人和幼儿对ΣPBDEs的日呼吸暴露量年几何均值分别为1.34和0.69 ng∙d-1，且以BDE-209为主（1.21和0.64 ng∙d-1）。呼吸是人体对PBDEs尤其是BDE-209的一条主要暴露途径。家庭在普通人群对PBDEs的呼吸暴露量中贡献最大（成人68%，幼儿90%）。工厂等特殊职业人群对PBDEs的暴露量最高可达普通人群的420倍。6）厦门家庭、办公室、机房和家具厂室内ΣPBDEs沉降通量年几何均值分别为6.1、3.0、1.1和179.8 ng∙(m2∙d)-1。室内降尘是人体对ΣPBDEs尤其是高溴BDEs的一条主要暴露途径。