北京市绿地土壤多环芳烃分布及健康风险评价

Polycyclic aromatic hydrocarbons in urban green space of Beijing: distribution and potential risk

以北京城区的公园绿地、居住区绿地64个表层土壤(0~5cm)为研究对象,研究了土壤多环芳烃(PAHs)的含量水平、空间分布以及终生致癌风险.结果表明:两类绿地中15种PAHs的含量无明显差异,公园绿地Σ15PAHs含量范围为1069~19002μg/kg,中值为4377μg/kg;居住区绿地Σ15PAHs含量范围为947~16882μg/kg,中值为4708μg/kg.且二环的萘、四环的芘以及五环的苯并(a)芘所占比例较大.污染较严重的区域主要分布在中心城区和城区西南.对成人和儿童终生致癌风险评价表明,目前正常暴露水平下绿地中PAHs对在其中活动的人群风险较低,但个别样点污染较重,其潜在的健康风险不容忽视.

To determine the concentration, spatial distribution, and health risk of 15 polycyclic aromatic hydrocarbons（PAHs） in urban green space, a total of 64 surface soil samples（0～5cm） were collected from park green space（PGS） and residential green space（RGS）. No significant difference was found between two types of green space. The content of Σ15PAHs in PGS ranged from 1069 to 19002μg/kg, with a median value of 4377μg/kg; And the content of Σ15PAHs in RGS ranged from 947 to 16882μg/kg, with a median value of 4708μg/kg. Naphthalene, pyrene and Benzo（a） pyrene contribute a lot to the total concentration. Samples with higher PAHs levels mainly distributed in the central and Southwest of the city. The incremental lifetime cancer risks（ILCRs） associated with exposures to PAHs in soil was calculated for children and adults, respectively. Results showed that ILCRs were quite low for humen exposure to the current urban green space under normal conditions. But individual samples were seriously polluted and its potential health risks can not be ignored.