济南市夏季环境空气中PBDEs的浓度分布及潜在风险分析

为准确评估济南市夏季环境空气中PBDEs（多溴联苯醚）的污染情况，利用气相色谱-负化学离子源-质谱（GC-NCI-MS）方法，对采集到的大气颗粒物滤膜和气相样品进行了分析，得到不同粒径颗粒相和气相PBDEs在济南市夏季环境空气中的质量浓度.结果表明:观测期间，济南市环境空气中TSP（总悬浮颗粒物）、PM₁₀和PM_2.5中的ρ（PBDEs）分别为（224.1±14.0）（156.5±43.7）（110.2±27.4）pg/m3，质量浓度较高的3种PBDEs单体分别为BDE209、BDE99、BDE183；气相中ρ（PBDEs）为（54.8±13.2）pg/m3，其中，质量浓度较高的单体分别为BDE209、BDE47、BDE99.通过主因子分析发现，不同粒径颗粒物上吸附的PBDEs特征单体不同，TSP中以五溴联苯醚为主，PM₁₀中以八溴联苯醚和五溴联苯醚为主，PM_2.5中则以五溴联苯醚、八溴联苯醚、十溴联苯醚为主.通过将2种模型的预测值和实测值进行比较发现，稳衡态模型比K_OA（辛醇-空气分配系数）模型更好地模拟了PBDEs的气-粒分配情况.在稳衡态模型下，PBDEs在气-粒分配中接近于平衡状态.高溴代PBDEs主要分布于颗粒相中，而低溴代PBDEs的真实情况不同于理论预测结果，BDE99及BDE47在颗粒相的分配比高于50%，说明济南市低溴代PBDEs也容易吸附在颗粒相中.根据计算的PBDEs呼吸暴露水平可知，PM_2.5上PBDEs呼吸暴露量占TSP呼吸暴露量的49.1%，儿童约是成人的1.5倍.济南市普通儿童和成人对BDE99最高总摄入量分别为234.78和169.57 pg/（kg·d），均低于BDE99最大允许摄入量260 pg/（kg·d）.根据US EPA（美国环境保护局）发布的PBDEs健康风险评价方法（EPA/540/R/070/002），利用国内外相关参数分别计算空气吸入致癌风险指数发现，济南市夏季环境空气中PBDEs的致癌风险处于较低水平.研究显示，济南市夏季环境空气中不同粒径颗粒物PBDEs的质量浓度处于较低污染水平，其产生的潜在健康风险也较低. 

Concentration Distribution and Potential Risks of Atmospheric PBDEs in Summer in Jinan City

To evaluate the pollution level of atmospheric PBDEs in summer in Jinan City, the concentrations of PBDEs in various particle sizes and gas phase were obtained using gas chromatography-negative chemical ionization-mass spectrometry (GC-NCI-MS) to analyze particle and PUF membrane samples. The results show that during the monitoring period the average concentrations of PBDEs on TSP, PM₁₀ and PM_2.5 in Jinan City were (224.1±14.0), (156.5±43.7) and (110.2±27.4) pg/m³, respectively; and the top 3 congeners of PBDEs with the highest concentration were BDE209, BDE99 and BDE183. The average concentration of gaseous PBDEs was (54.8±13.2) pg/m³; and the top 3 congeners were BDE209, BDE47 and BDE99. A SPSS 22.0 software was used to conduct the principal factor analysis, indicating that the adsorbed PBDEs on different particle sizes were different:pentabromodiphenyl ether the dominant compound on the TSP, octabromo and decabromodiphenyl ether was mainly associated with the PM₁₀, and pentabromo, octabromo, decabromodiphenyl ether were mainly on the PM_2.5. By comparing the predicted values of the two models with the measured values, it was found that the steady-state model simulation of the air-particle distribution of PBDEs was more reliable than the equilibrium model. Based on the steady model, the PBDEs in Jinan City were near equilibrium state in gas-particle distribution. High-brominated PBDEs were mainly distributed in the particulate form, while the actual concentration of low-brominated PBDEs was different from the model predicted results. For instance, the mass fraction of BDE99 and BDE47 on particles were higher than 50%, indicating that low-brominated PBDEs in Jinan also tended to be adsorbed on the particles. According to the calculations of respiratory exposure levels of PBDEs, the values on PM_2.5 accounted for 49.1% of TSP respiratory exposure, indicating that the influence on children was approximately 1.5 times as many as adults. The total intake of BDE99 for children and adults in Jinan City was 234.78 and 169.57 pg/(kg·d), respectively, which was lower than the suggested maximum intake of BDE99 (260 pg/(kg·d)). According to the PBDEs health risk assessment method of EPA (EPA/540/R/070/002), it was found that the inhalation cancer risk of PBDEs in summer air in Jinan, calculated using the reported parameters, was very low. The results showed that the mass concentration of PBDEs with different particle sizes in the ambient air of Jinan City in summer was at a lower pollution level, and the potential health risks were also lower.