安徽省室内降尘中多环芳烃分布及来源解析

采集安徽省内14个采样点的24个室内降尘样品,检测16种多环芳烃(PAHs)含量.结果表明,安徽省不同区域室内降尘中∑PAHs浓度范围为0.52~89.3μg/g,平均浓度为20.7μg/g.降尘中PAHs以5环为主,其次是4环和3环.PAHs组成分析表明,几乎全部样品中PAHs均以高环(4~6环)为主,其高达60.5%~97.0%,仅在4个样品中检出了较高比例的低环PAHs(2~3环).这说明多数室内降尘中PAHs污染由交通运输(汽车和船舶)以及化工厂等高温燃烧排放造成.而安庆、芜湖及六安地区可能存在较严重的石油污染或煤、木材等低温燃烧源污染.公共场所、城市家庭和农村家庭降尘中PAHs的浓度存在明显的差异,总体上呈现:公共场所城市家庭农村家庭.异构体分析表明,公共场所和城市家庭内存在混合来源,而农村家庭以燃烧源为主.致癌能力分析表明,城市家庭降尘中的苯并a]芘当量(Ba PE)值略高于农村家庭.公共场所降尘中的Ba PE值远大于家庭场所,是农村家庭或城市家庭场所的2倍多.

Distribution and source analysis of polycyclic aromatic hydrocarbons in indoor dust from Anhui Province,China

Indoor dust samples (n=24) were collected from 14 locations in Anhui province, and concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) were measured. The results showed that the sum concentrations of 16PAHs (ΣPAHs) in all the samples ranged from 0.52 to 89.3 μg/g, with a mean value of 20.7 μg/g. Five-ring PAH was the predominant PAH component in all samples, followed by 4-ring and 3-ring PAHs. PAHs with high-molecular weight (4~6rings) are the predominant PAHs in most samples, ranging from 60.5% to 97.0% in ΣPAHs. Relatively high percentages of PAHs with low-molecular weight (2~3rings) were detected in only 4samples. This indicates the significant contribution of vehicle (automobiles and ships) and high temperature combustion from chemical plant to PAHs emission in most locations. However, potential high PAHs emission from oil, fuel spills and low temperature combustion from coal or woods might present in Anqing, Wuhu, and Liu'an. Significant differences of ΣPAHs were observed in the indoor dust from urban public places, urban family housings, and rural family housings, following the order of urban public places> urban family housings> rural family housings. According to the diagnostic ratio analysis, PAHs in dust from the public places and urban family housings were derived from the mixed source, while PAHs in dust from rural family housings were mainly derived from the combustion sources. Furthermore, carcinogenic risk assessment of PAHs indicated that the BaPE values in urban family housings were slightly higher than those in rural family housings. Much higher BaPE values of the dust from the urban public places were calculated, which were two times higher than the BaPE values of the dust from the urban and rural family housings.