对西安市某初中学校冬春季4个不同粒径大气颗粒物中多环芳烃(PAHs)水平的研究表明,此中学室内外PM2.5,样品中PAHs的平均浓度为82.57ng·m-3,室外PAHs浓度大于室内浓度.其中具有强致癌性组分BaP的平均浓度为3.24ng·m-3.PM2.5,中PAHs浓度明显高于其他大粒径颗粒物的PAHs浓度,这表明颗粒物粒径越小PAHs浓度就越高,也间接表明其对人体健康,尤其是青少年健康的影响也越大.研究期间PAHs的BaP平均等效浓度(BEQ)为9.30,且室外BEQ值大于室内. “,”Characteristics and health risk assessment of polycyclic aromatic hydrocarbons(PAHs) in PM25 different particle size were measured in a junior middle school in Xi'an from 8 March 2012 to 22 March 2012. The average PAHs concentration was 82.57 ng·m-3, with higher average concentration determined in outdoor than that in indoor environment. Moreover, the average concentration of BaP with the strongest carcinogenicity was 3.24 ng·m-3 PAHs concentration in PMO25 was much higher than that in other bigger size particles, leading to the strongest health hazard effects on human, especially teenagers. The average BEQ value was 9.30, and outdoor BEQ values were greater than those in indoor.