四川省不同地区自来水中全氟化合物的污染特征及健康风险评估

Health risk assessment and pollution characteristics of perfluoroalkyl substances in tap water of Sichuan Province

采用超高效液相色谱-质谱联用仪分析了四川省10个地区自来水中12种全氟化合物(perfluoroalkyl substances, PFASs)的含量,其中全氟化合物浓度水平最高的是宜宾地区,∑PFASs为41.2 ng·L^(-1),浓度水平最低的是绵阳地区,为4.17 ng·L^(-1).全氟辛烷羧酸(perfluroroocantanoic acid,PFOA)是四川地区自来水中主要的PFASs,占总全氟化合物的28%～89%(宜宾地区8.6%),其次为全氟己酸(perfluorohexanoate,PFHxA)、全氟辛烷磺酸(perfluorooctane sulfonate, PFOS)和全氟壬酸(perfluorononanoate,PFNA),这表明自来水中的主要污染物为中短碳链(C≤10)的全氟化合物.另外,通过计算PFASs的危险商值(risk quotients, RQ),发现四川地区自来水中PFOA、PFOS、PFHxS、PFBS和PFHxA的风险商值均小于1,不会对当地居民带来直接的健康风险.

Twelve perfluoroalkyl substances(PFASs) were analyzed in tap waters collected from 10 different cities in Sichuan Province using an ultra-high performance liquid chromatography tandem mass spectrometry(UPLC-MS/MS). The results show that ∑PFASs in Yibin area displayed the highest concentration level at 41.2 ng·L-1, while Mianyang had the lowest concentration(4.17 ng·L-1). Perfluroroocantanoic acid(PFOA) was the predominant PFASs in tap waters of Sichuan Province, which accounted for 28%~89% of ∑PFASs with an exception of Yibin(8.6%), followed by perfluorohexanoate(PFHxA), perfluorooctane sulfonate(PFOS) and perfluorononanoate(PFNA). It suggests that short-and median-chain PFASs(C≤10) were the main contaminants in tap water. Finally, risk quotients(RQs) were calculated and it was found that RQs values of PFOA, PFOS, PFHxS, PFBS and PFHxA were lower than 1 in all the tap waters, suggesting no direct health risk to local residents.