Department of Applied Environmental Science (ITM), Stockholm University, SE-10691 Stockholm, Sweden.
Environ Sci Technol. 2009 Dec 15;43(24):9274-80. doi: 10.1021/es901448p.
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.
采用全球尺度的归宿与传输模型，研究了全氟辛烷磺酸（PFOS）及其挥发性全氟辛基磺酰氟（POSF）前体化合物在环境中的背景浓度的历史和未来变化趋势。首先，针对 1957-2010 年期间，估算了 PFOS 及其前体化合物的全球排放清单。我们将该清单作为输入，纳入全球尺度的污染物归宿模型，并将模拟浓度与实地数据进行了比较。模拟的重点是考察 PFOS 和挥发性前体化合物的浓度如何响应 2000-2002 年期间发生的主要生产淘汰。海洋表面水中 PFOS 的模拟浓度通常与实地数据相差一个数量级，主要由该物质的直接排放所决定。相比之下，本研究中所考虑的前体化合物的模拟浓度，无论是在生产淘汰之前还是之后，均低于实测浓度。由于生产淘汰，源区海洋表面水中 PFOS 的模拟浓度缓慢下降，而在偏远地区，浓度仍将持续增加，直至 2030 年。相比之下，在所有地区，大气和海洋表面水这两个组分中前体化合物的模拟浓度，均对生产淘汰做出快速响应（即迅速下降至低得多的水平）。就野生动物生物监测数据而言，由于前体化合物具有生物可利用性，并在体内降解为 PFOS，因此至少可以假定，在一些海洋生物中观察到的 PFOS 体内负荷下降趋势，可能归因于这种暴露途径。在其他地区栖息的海洋生物中观察到的 PFOS 体内负荷持续增加，可能反映了主要通过环境中该化合物的生产和使用以及前体化合物的降解所导致的 PFOS 暴露。
