Department of Civil and Environmental Engineering , Princeton University , Princeton , New Jersey 08544 , United States.
Environ Sci Technol. 2019 Oct 1;53(19):11410-11419. doi: 10.1021/acs.est.9b04047. Epub 2019 Sep 18.
Incubations with pure and enrichment cultures of sp. strain A6 (A6), an autotroph that oxidizes ammonium to nitrite while reducing ferric iron, were conducted in the presence of PFOA or PFOS at 0.1 mg/L and 100 mg/L. Buildup of fluoride, shorter-chain perfluorinated products, and acetate was observed, as well as a decrease in Fe(III) reduced per ammonium oxidized. Incubations with hydrogen as a sole electron donor also resulted in the defluorination of these PFAS. Removal of up to 60% of PFOA and PFOS was observed during 100 day incubations, while total fluorine (organic plus fluoride) remained constant throughout the incubations. To determine if PFOA/PFOS or some of their degradation products were metabolized, and since no organic carbon source except these PFAS was added, dissolved organic carbon (DOC) was tracked. At concentrations of 100 mg/L, PFOA/PFOS were the main contributors to DOC, which remained constant during the pure A6 culture incubations. Whereas in the A6 enrichment culture, DOC decreased slightly with time, indicating that as defluorination of PFOS/PFOA occurred, some of the products were being metabolized by heterotrophs present in this culture. Results show that A6 can defluorinate PFOA/PFOS while reducing iron, using ammonium or hydrogen as the electron donor.
在 0.1mg/L 和 100mg/L 的浓度下，用纯培养物和 sp. 菌株 A6（A6）的富集培养物进行孵育，A6 是一种自养生物，可将铵氧化为亚硝酸盐，同时还原三价铁。观察到氟化物、短链全氟化合物产物和乙酸盐的积累，以及每氧化一铵还原的三价铁减少。用氢气作为唯一的电子供体进行孵育也导致这些 PFAS 的脱氟。在 100 天的孵育过程中，观察到高达 60%的 PFOA 和 PFOS 被去除，而整个孵育过程中总氟（有机氟加氟化物）保持不变。为了确定是否代谢了 PFOA/PFOS 或它们的一些降解产物，并且由于除了这些 PFAS 之外没有添加任何有机碳源，因此跟踪了溶解有机碳 (DOC)。在 100mg/L 的浓度下，PFOA/PFOS 是 DOC 的主要贡献者，在纯 A6 培养物孵育过程中保持不变。而在 A6 富集培养物中，DOC 随时间略有下降，表明随着 PFOS/PFOA 的脱氟，一些产物被该培养物中存在的异养生物代谢。结果表明，A6 可以在还原铁的同时脱除 PFOA/PFOS，使用铵或氢气作为电子供体。
