Objective To understand the pollution characteristics and sources of polycyclic aromatic hydrocarbons (PAHs) in PM 25 in Guangzhou in 2018, and we evaluate the health risk of the population.
Methods From January to December 2018, PM 25 samples were collected from 3 administrative districts in Guangzhou, and the content of 16 PAHs was analyzed. The main source was identified by the characteristic ratio method, and the carcinogenic equivalent of PAHs was calculated using benzo[a]pyrene as a reference. Concentration and mutagenic equivalent concentration, the lifelong carcinogenic excess risk and life expectancy loss of the population were calculated.
Results The average mass concentration of PAHs in PM 25 in 2018 was 5.363ng/m3. PAHs are mainly composed of 4to 5rings PAHs. The main sources of PAHs are vehicle exhaust and coal combustion. The average carcinogenic equivalent concentration (TEQ) is 1.20 ng/m 3, and the average mutagenic equivalent concentration MEQ is 0.99 ng/m 3. The lifetime risk of excess carcinogenicity of PAHs to male adults, adolescents, and children through respiratory exposure is: 1.670 × 10 -6, 2.220 × 10 -6, and 4.479 × 10 -6. The lifetime carcinogenic excess risks to female adults, adolescents, and children are 1.741 × 10 -6, 2.333 × 10 -6, and 4.099 × 10 -6.
Conclusion In 2018, the pollution level of PAHs in PM 25 in Guangzhou was low. The main sources were vehicle exhaust and coal combustion. The population health risk of PAHs in PM 25 was within the acceptable range.
摘要：目的了解2018年广州市PM 25中多环芳烃(PAHs)的污染特征和来源，并进行人群健康危险度评估。 方法2018年1 一 12月采集了广州市3个行政区的PM 25样品，分析16种PAHs的含量，利用特征比值法识别其主要来 源，以苯并[al芘为参照计算PAHs致癌等效浓度和致突变等效浓度，计算人群终身致癌超额危险度和预期寿命损失。 结果 2018年PM 25中PAHs总质量浓度平均值为5.363 ng/m 3。PAHs的组成均以4~5环PAHs为主。PAHs的主要来源 为机动车尾气和煤燃烧。致癌等效浓度(TEQ)的平均值为1.20 ng/m 3，致突变等效浓度（MEQ)平均值为0.99 ng/m 3； PM 25中PAHs对男性成人、青少年和儿童的终身致癌超额危险度分别为1.670x10 -6，2.220x10 -6和4.479x10 -6,对女性成 人、青少年和儿童的终身致癌超额危险度分别为1.741x10 -6，2.333x10 -6和4.099x10 -6。 结论2018年广州市大气PM 25 中PAHs的污染程度较低，主要来源为机动车尾气和煤燃烧，PM 25中PAHs的人群健康风险处在可接受范围内。