Distribution, source characterization and inventory of perfluoroalkyl substances in Taihu Lake, China.
The levels, distribution, possible sources, and inventory of perfluoroalkyl acids (PFAAs) in the eutrophic freshwater Taihu Lake, East China were investigated in this study. Among the target 11 PFAAs, perfluorooctanoic acid (PFOA) (2.15-73.9 ng L(-1)) and perfluorohexanoic acid (PFHxA) (<LOQ-22.2 ng L(-1)) were the dominant components in surface water, followed by perfluorooctanesulfonic acid (PFOS) with the maximum concentration of 10.5 ng L(-1). PFOS was also dominant (0.13-6.95 ng g(-1) dw) in the sediments, accounting for 15-85% of ΣPFAAs concentrations in 70% of the sediment samples. Sediment-water partitioning coefficients showed that logKOC increased linearly with the increasing chain length, with the logKOC values increased by 0.1-0.4 log unit with each CF2 moiety from C8 to C12 perfluorinated carboxylic acids. Three specific molecular ratios, PFOS/PFOA, PFOA/PFNA and PFHpA/PFOA were used to characterize the potential sources. It indicated that the majority of pollutants was from direct emissions from manufacturing processes. The PFOA/PFNA ratios between 1.7 and 56.8 in surface water suggested the influence of secondary sources such as the degradation of volatile precursor substances. Given the high ratios of PFHpA/PFOA (0.05-7.93), it also indicated the influence from atmospheric deposition to the epilimnion. The predicted environmental concentrations were calculated from European Union system for the evaluation of substances model (EUSES). As expected, the predicted environmental concentration (PEC) of PFOS in sediment fit well to the monitored level of PFOS in this region, and the inventory of ΣPFCA and PFOS were estimated to be 989 kg and 646 kg in Taihu Lake.
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Changsheng
C
Guo
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Yuan
Y
Zhang
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Xin
X
Zhao
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Ping
P
Du
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Sisi
S
Liu
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Jiapei
J
Lv
Ecological and Environmental Monitoring Center, Sino-Singapore Tianjin Eco-city, Tianjin 300467, China.
Fengxia
F
Xu
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
Wei
W
Meng
State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China. Electronic address: xujian@craes.org.cn.
Jian
J
Xu
D017738:Alkanesulfonic Acids / Q000032:analysis*; D002208:Caproates / Q000032:analysis*; D002210:Caprylates / Q000032:analysis*; D002681:China; D004784:Environmental Monitoring / Q000379:methods*; D005466:Fluorocarbons / Q000032:analysis*; D019015:Geologic Sediments / Q000737:chemistry; D060106:Lakes / Q000737:chemistry*; D008962:Models, Theoretical; D011379:Prognosis; D014874:Water Pollutants, Chemical / Q000032:analysis*
D017738:Alkanesulfonic Acids; D002208:Caproates; D002210:Caprylates; D005466:Fluorocarbons; D014874:Water Pollutants, Chemical; C023036:perfluorooctanoic acid; C076994:perfluorooctane sulfonic acid; C479228:perfluorohexanoic acid
Inventory; Perfluoroalkyl acids (PFAAs); Source; Taihu Lake