Distribution And Risk Assessment Of Perfluorinated Compounds In Water Of Shuangtaizi Estuary

As a new kind of emerging organic pollutants, perfluorinated compounds (PFCs) have attracted researchers’ attention. PFCs have been widely detected in various environmental mediums, especially in water environment. PFCs not only damage aquatic organisms to some extent but also threatened human health with food or drinking water. Therefore, it was critical to investigate the distribution and ecological risk of PFCs in important water bodies.PFCs pollutions of water bodies mainly resulted from human activities. Large amount of wastewater entered nearby rivers, lakes and other surface water and ultimately affected water quality of terminal water bodies. Shuangtaizi river is the only one channel of Liaohe river into sea, passing through Liujianfang and flowing into Liaodong bay. As a semi-closed bay, Liaodong bay has poor ability of self-purification, and therefore is fairly sensitive to water pollutions. Recently, some studies on pollutions of heavy metals and nutrients of Shuangtaizi estuary have been reported, but there are few studies nearly relevant to PFCs pollution. In the present study,15 kinds of PFCs (including 11 kinds of perfluorinated carboxylic acids and 4 kinds of perfluorosulfonic acids) in water samples from Shuangtaizi estuary were analyzed by high performance liquid chromatography tandem mass spectrometry detector (HPLC-MS/MS) combined with SPE pretreatment. Distribution rules and ecological risk were investigated based on datas of PFCs concentrations in water samples. The experimental results demonstrated that Shuangtaizi estuary water body has suffered from PFCs pollution and primary conclusions are as follows:(1) The mean concentration (maximum concentration) of FCs in river samples and seawater samples were 110.366 (207.028) and 121.318 (209.350) ng/L, respectively. Shorter chains PFBA and PFPeA were the main PFCs pollutants in water samples of Shuangtaizi estuary, followed by PFOA and PFHxA. Among 4 kinds of perfluorosulfonic acids detected in this study, PFBS was the primary pollutant and its concentration was higher than that of PFOS.(2) Compared with bottom water samples, the change of ΣFCs concentration in surface samples was obvious, which showed an increasing trend along the direction of flow.(3) ∑FCs concentration in seawater samples decreased gradually with the distance from estuary. ∑FCs concentrations in seawater samples close to Daliao river were relatively higher. For most of sampling sites,∑FCs concentration in surface water sample was lower than that of bottom water sample;(4) Risk assessment by different models showed that PFOS and PFOA in Shuangtaizi estuary temporarily would not produce immediate harm to ecological and human health.