沈阳地区水环境和生物样品中全氟化合物的污染分布特征

采用高效液相色谱/电喷雾负电离源串联质谱法对沈阳市各类水环境和生物样品中全氟化合物(PFCs)进行测定,研究了PFCs的河流分布及季节分布特征.同时,对通过饮用水及家禽和鱼摄入全氟辛烷磺酸(PFOS)和全氟辛酸(PFOA)的人体健康风险进行了评价.结果表明,沈阳市各类水环境样品中总PFCs浓度范围为nd～6.01ng·L-1,平均浓度为5.23ng·L-1.PFOS和PFOA是沈阳地区所有水环境样品中最主要的PFCs污染物,浓度范围分别为nd～2.83ng·L-1和nd～5.71ng·L-1,平均浓度分别为1.11和2.13ng·L-1.细河的PFOS含量最高,约为浑河PFOS含量的2倍,蒲河PFOS含量的3倍.一些PFCs化合物之间呈正相关关系,说明其可能具有相同的来源.PFOS与PFOA之间无相关关系,由此推断沈阳水体中二者具有不同来源.浑河流经沈阳市时,PFOS和PFOA浓度升高.流经沈阳市区后,PFOS和全氟己烷磺酸钾(PFHxS)浓度明显升高.细河中PFHxS也有检出,表明沈阳市是周边水体中PFOS及PFHxS的主要污染来源.丰水期地表水中PFOS和PFOA浓度与枯水期相比没有明显差异,但丰水期水中PFCs组成更为丰富,出现了大量全氟庚酸(PFHpA).沈阳地区自来水中PFOS和PFOA浓度平均值分别为0.39和0.85ng·L-1,最高浓度分别为1.16和2.55ng·L-1,均低于美国饮用水健康参考值.沈阳生物样品中PFOS和全氟十一酸(PFUnDA)是最普遍的化合物.总PFCs平均含量在鱼样品中为6.59ng.g-1(以干重计),鸡和鸭血清样品中分别为1.65和0.69ng·mL-1,鸡和鸭肝脏样品中分别为0.41和1.68ng.g-1(以干重计),与文献报道相比处于较低水平.

Levels and distribution of perfluorinated compounds in water and biological samples from the Shenyang area,China

Perfluorinated compounds (PFCs) were quantified in samples collected from different surface waters, groundwaters and biota in the Shenyang area by HPLC/negative ESI/MS/MS. The human health risk of intake of PFOS (perfluoroalkylsulfonates) and PFOA (perfluorooctanoic acid) via drinking water, fish and domestic poultry were evaluated. The total PFCs in surface water samples from branches of the Liaohe River ranged from nondetectable to 6.01, averaging 5.23 ng·L-1. PFOS and PFOA were the main PFCs, with a range of nd~2.83 (average 1.11) ng·L-1 and nd~5.71 (average 2.13) ng·L-1, respectively. The average PFOS concentration in the Xi River waters was twice that of the Hun River waters, and 3 times higher than that of the Pu River waters. There were positive correlations among several PFCs, suggesting a common source. There was no relationship between PFOS and PFOA, suggesting they were from different sources in the city of Shenyang. Concentrations of PFOS and PFOA in the Hun River increased towards Shenyang and PFOS and PFHxS (perfluorohexanesulfonate) were significantly higher in the section of the Hun River downstream of Shenyang. PFHxS also occurred in the Xi River which receives sewage from Shenyang, indicating that urban sewage was the source of PFOS and PFHxS in surface waters in this area. Concentrations of PFOS and PFOA in the rainy season showed no significant difference from the dry season in Hun River water, but more PFCs occurred in the rainy season, characterized by a substantial increase of PFHpA (perfluoroheptanoic acid). The mean concentrations of PFOS and PFOA in tap water from Shenyang were 0.39 and 0.85 ng·L-1, with maximum levels of 1.16 and 2.55 ng·L-1, respectively. All samples were below the US drinking water reference values for human health. PFOS and PFUnDA (perfluoroundecanoic acid) were the most abundant compounds in the biota samples. The mean concentrations of PFCs in fish were 6.59 ng·g-1 dry weight. For chicken and duck, levels were 1.65 and 0.69 ng·mL-1 in the serum samples and 0.41 and 1.68 ng·g-1 dry weight in the liver samples, showing a relatively low PFC pollutant level compared with those reported in other countries.