Modeling the Global Fate and Transport of Perfluorooctane Sulfonate (PFOS) and Precursor Compounds in Relation to Temporal Trends in Wildlife Exposure
Modeling the Global Fate and Transport of Perfluorooctane Sulfonate (PFOS) and Precursor Compounds in Relation to Temporal Trends in Wildlife Exposure
复制标题
DOI：
10.1021/es901448p
复制
发表时间：
2009-12-15
影响因子：
11.4
通讯作者：
Cousins, Ian T.
中科院分区：
文献类型：
--
作者：
Armitage, James M.;Schenker, Urs;Cousins, Ian T.
采用了一个全球范围的归宿和迁移模型，以调查环境中全氟辛烷磺酸和挥发性全氟辛基磺酰氟前体化合物的环境浓度的历史和未来趋势。首先，估算了1957-2010年期间全氟辛烷磺酸及其前体化合物的全球排放清单。我们使用这个清单作为输入到一个全球规模的污染物归宿模型，并比较了模拟的浓度与现场数据。模拟的主要重点是研究全氟辛烷磺酸和挥发性前体化合物的模拟浓度如何应对2000-2002年期间发生的大规模生产淘汰。模拟得出的表层海洋沃茨中全氟辛烷磺酸的浓度一般在实地数据的5倍以内，主要是该物质的直接排放。相比之下，本研究中考虑的前体化合物的模拟浓度低于生产淘汰前后的实测浓度。模拟的来源区域表层海水中的全氟辛烷磺酸浓度随着生产的逐步淘汰而缓慢下降，而偏远地区的浓度将持续增加，直至2030年。相比之下，所有区域的大气和表层海水舱中前体化合物的模拟浓度对生产逐步淘汰的反应迅速（即，迅速下降到更低的水平）。关于野生动物生物监测数据，由于前体化合物具有生物可利用性，并在体内降解为全氟辛烷磺酸，因此至少有理由认为，在某些海洋生物体内观察到的全氟辛烷磺酸体内负荷下降趋势可归因于这一接触途径。在其他区域栖息的海洋生物体内观察到的全氟辛烷磺酸负荷持续增加，可能主要反映了由于生产和使用全氟辛烷磺酸以及前体化合物的降解而暴露于环境中的全氟辛烷磺酸本身。
A global-scale fate and transport model was applied to investigate the historic and future trends in ambient concentrations of perfluorooctane sulfonate (PFOS) and volatile perfluorooctane sulfonyl fluoride (POSF)-based precursor compounds in the environment. First, a global emission inventory for PFOS and its precursor compounds was estimated for the period 1957-2010. We used this inventory as input to a global-scale contaminant fate model and compared modeled concentrations with field data. The main focus of the simulations was to examine how modeled concentrations of PFOS and volatile precursor compounds respond to the major production phase-out that occurred in 2000-2002. Modeled concentrations of PFOS in surface ocean waters are generally within a factor of 5 of field data and are dominated by direct emissions of this substance. In contrast, modeled concentrations of the precursor compounds considered in this study are lower than measured concentrations both before and after the production phase-out. Modeled surface ocean water concentrations of PFOS in source regions decline slowly in response to the production phase-out while concentrations in remote regions continue to increase until 2030. In contrast, modeled concentrations of precursor compounds in both the atmosphere and surface ocean water compartment in all regions respond rapidly to the production phase-out (i.e., decline quickly to much lower levels). With respect to wildlife biomonitoring data, since precursor compounds are bioavailable and degrade to PFOS in vivo, it is at least plausible that declining trends in PFOS body burdens observed in some marine organisms are attributable to this exposure pathway. The continued increases in PFOS body burdens observed in marine organisms inhabiting other regions may reflect exposure primarily to PFOS itself, present in the environment due to production and use of this compound as well as degradation of precursor compounds.