Health Risk Assessment On4Polycyclic Aromatic Hydrocarbon In Reclaimed Water

The situation of water resources shortage is becoming increasingly serious atpresent. Therefore, reclaimed water is being reused more and more widely. Thefollowing security problems have also aroused more extensive attention as well. Thereasonable and effective health risk evaluation on reclaimed water is necessary toprovide reliable security for scaling water reuse, ensuring health and safety of publicand occupation at the same time on the basis of saving water resource. As a result,scientific support and decision-making basis for the regeneration of water safety andquality standards could be provided reliably.In this paper, some user-end of reclaimed water in city was chosen as theresearch object. After qualitative detection of some organic species,4representativePAHs were seclected for the following quantitative detection. That was, naphthalene(NAP), anthracene (ANT), as well as carcinogenic benzo(a)anthrancene (BaA) andbenzo(a)pyrene (BaP). The result showed that BaP and total PAHs could beconformed to relevant water supply quality standards. Then the datas were analyzedstatistically. It was shown that the results of each index were in line with thelognormal distribution. The related parameters were also accessable.According to the detection datas and lognormal distribution function, combinedwith the hazards of toxic and exposue parameters, this paper calculated carcinogenicand noncarcinogenic risk and obtained the risk probability distribution by Crystal Ballwith the4PAHs above as risk factors. In general, the noncarcinogenic risk level ishigher than that of carcinogenic risk, while the risk level of occupation exposure ismuch higher than that of public exposure. The carcinogenic risk under each approachachieves acceptable levels, part to negligible levels, including BaP reaching as high as80.51%, about4times of BaA. The noncarcinogenic risk under occupation exposureexceeds the maximum acceptable level, leading to necessary of effective protectivemeasures. The risk level of4PAHs above arranges as BaA>BaP>NAP>ANT in totalnoncarcinogenic risk, including the propotion of BaA up to67.17%.