某城市回用水中多环芳烃的含量及其有机提取物的细胞毒性

Levels of Polycyclic Aromatic Hydrocarbons in Reclaimed Water Used in a City and the Cytotoxicity of Organic Extracts

目的了解某城市回用水中多环芳烃(PAHs)的分布特征及对细胞的毒性作用。方法分别于丰水期(8月)、枯水期(3月)采集某城市污水处理厂回用水处理工艺中的入水和回用水,预处理水样后,采用固相萃取法萃取其中的有机物,然后采用气相色谱-质谱法(GC-MS)检测水样中16种PAHs的含量,利用MTT法研究回用水对CHL细胞的毒性作用。结果丰水期和枯水期两次水样中均检出PAHs,主要为芴和菲,其次为萘、苊、二氢苊、蒽、荧蒽、芘等。丰水期入水水样中16种PAHs的总浓度为1 777.9 ng/L,回用水水样为1 380.1 ng/L;枯水期入水水样中16种PAHs的总浓度为2 225.1ng/L,回用水水样为1 827.1 ng/L。丰水期PAHs含量低于枯水期,但是丰水期中的PAHs种类要高于枯水期。经过回用水处理工艺处理后,回用水中PAHs含量均有所下降。CHL细胞毒性随着原水浓度的增加逐渐增强。结论城市回用水中含有PAHs,并且对CHL细胞有一定的毒性作用。

Objective To understand the distribution of polycyclic aromatic hydrocarbons（PAHs） in the reclaimed water in a city and the toxic effects on CHL cells.Methods The entry and reclaimed water were collected during wet period（August） and dry season（March） in the water treatment process of a municipal wastewater treatment plant.After pretreatment,solid phase extraction was used to extract the organic matter,and then the content of 16 kindsof PAHs were detected by gas chromatography-mass spectrometry（GC-MS）.And MTT method was used to get the toxic effects of organic extracts of reclaimed water on CHL cell.Results PAHs were detected both in wet period and dry season,the dominant chemicals were fluorene and phenanthrene,followed by naphthalene,acenaphthylene,acenaphthene,anthracene,fluoranthene and pyrene.During wet period,the total concentration of 16 kinds of PAHs in the entry water and reclaimed water were 1 777.9 ng/L and 1 380.1 ng/L respectively,while during wet season were 2 225.1 ng/L and 1 827.1 ng/L respectively.The concentration of PAHs in wet period was lower than the dry season,but the species of PAHs in wet period was more.After the water treatment process,the concentration of PAHs in reclaimed water declined.The toxic effects increased with the concentration of raw water increased.Conclusion The reclaimed water contains PAHs,and has toxic effects on CHL cell.Further improvement of the reclaimed water treatment process is needed.