城市土地置换过程中土壤多环芳烃污染的健康风险评价

ON HUMAN HEALTH RISK ASSESSMENT OF SOIL PAHs CONTAMINATION DURING URBAN LAND REPLACEMENT

利用健康风险评价方法判定污染土壤是否需要修复或再次开发已成为一个新的研究领域。以某区域土地置换开发为案例,结合区域未来土地利用类型,采用健康风险评价模型对土壤多环芳烃(PAHs)污染可能给未来入住人群带来的健康风险进行初步评价。结果显示,在正常情况与极端情况两种暴露场合下,考虑直接接触不慎摄入、呼吸土壤尘和皮肤直接接触土壤3种途径,计算出的土壤PAHs污染的致癌风险相对较高,部分点位已经超过了人体健康可接受的致癌风险程度。且以敏感人群儿童为例,利用摄入量和风险评价反推得出,当土壤中PAHs含量低于634μg/kg时,在极端情况下,儿童致癌风险可降低到可接受的致癌风险水平。随着环境管理工作的深入发展,在城市土地置换过程中应逐步加强环境健康风险评价方面的研究。

Using human health risk assessment （HRA） procedures to determine the remediation or redevelopment of contaminated site has become a new research area. In the paper, based on the future land use patterns,the HRA model was applied to evaluate the health risk brought by PAHs contamination in a site for redevelopment. The results indicated that under the two exposure scenarios including the normal condition and the extreme condition, and three exposures, including inhalation exposures, dermal exposures and in- gestion exposures,the carcinogenic risk brought by PAHs contamination was comparatively high,and exceed the acceptable health risk lever in several sites. Take the sensitive children for example, the risk-based PAHs remedial goal of 634μg/kg was calculated for reducing the carcinogenic risk to acceptable level un- der the extreme condition. In future,with the development of environmental management,the HRA should be strengthening during urban land redevelopment.