保定市城区典型家庭室内PM2.5中BDE-47的污染特征研究

Particular features of BDE-47 in urban residential indoor PM:a case study in Baoding,China

以保定市为研究区域,采集城区家庭室内一年四季的PM2.5样品,对家庭室内PM2.5的质量浓度水平和其中BDE-47污染特征、季节变化、灰霾天气的影响以及呼吸暴露水平等进行研究。结果表明,家庭室内PM2.5的质量浓度范围为42.0~180μg/m^3,室内外空气中PM2.5质量浓度具有良好相关性。家庭室内PM2.5中BDE-47的质量浓度为0.28~12.1 pg/m^3,平均质量浓度为(3.24±3.08)pg/m^3,与文献报道水平相近。家庭室内PM2.5中BDE-47的质量浓度具有明显的季节性,冬季室内PM2.5中BDE-47的水平显著高于其他季节(p<0.05),春季和秋季的质量浓度水平相近但显著高于夏季(p<0.05)。灰霾天家庭室内PM2.5中BDE-47的质量浓度略高于非灰霾天,但差异并不显著(p>0.05)。呼吸暴露风险评估结果表明,儿童和成人对家庭室内PM2.5中BDE-47的呼吸摄入量分别为2.81~6.05 pg/(kg·d)和1.55~3.33 pg/(kg·d);BDE-47对儿童和成人的致癌风险分别为4.21×10^-4~9.08×10^-4和2.32×10^-4~5.00×10^-4,均超过世界卫生组织规定的可接受的癌症风险1.0×10^-4,表明居民暴露室内PM2.5中BDE-47具有潜在致癌风险。

The present paperis intended to investigate the roomin PM2.5 concentration rate as well as some other influential factors concerned,the seasonal variations and human inhalation exposure in the residential room-in PM2.5-bound polybrominated diphenyl ethers(PBDEs)in Baoding,one of the heaviest polluted urban zones in the country in terms of annual period.For the research purpose,we have collected a total of 52 PM2.5 samples by using a sampler for the air particulate matte collector device from4 residential homes,representing different ages and house living styles during a period from March,2018,to February,2019.In our paper,we have adopted gas chromatograph-mass spectrometer(short for GC-MS)2,2,4,4’-BDE(labeled as BDE-47)as the model compound of PBDEs to determine the PM2.5-bound BDE-47.The range concentration of the room-in PM2.5 has been found to be of 42.0-180μg/m^3 with the medium indooroutdoor correlations for the PM2.5.At the same time,the range and mean concentrations of BDE-47 in the residential indoor PM2.5 have been discovered as 0.28-12.1 pg/m^3 and(3.24±3.08)pg/m^3,respectively,which is similar to those reported from other urban areas in the country.While we were observing the significant seasonal variations of BDE-47 concentrations of the room-in PM2.5,we have found that the levels in spring and autumn turn to be similar,whereas they are significantly higher than those in summer(p<0.05)and in winter than in other seasons(p<0.05).The effect of haze episodes on the occurrence of indoor PM2.5 BDE-47 has also been discussed.The results of our study show that the levels of BDE-47 in indoor PM2.5 in haze episodes prove to be marginally higher than those in normal days,but not statistically significant(p>0.05).Based on the preliminary exposure and health risk assessment both for children and adults,the exposure to indoor PM2.5-bound BDE-47 has been estimated to be 2.81-6.05 pg/(kg·d)and 1.55-3.33 pg/(kg·d),respectively,whereas the accounted cancer risk of the room-in PM2.5-bound BDE-47 for children and adults were to be 4.21×10^-4-9.08×10^-4 and 2.32×10^-4-5.00×10^-4,which proves higher than that the data acceptable cancer risk(1.0×10^-4)recommended by the World Health Organization under the UN.And,therefore,it would become a potential cancer risk for residents,especially for children,whose exposure limit to the room-in PM2.5 is just bound to BDE-47.