摘要
N-乙基全氟辛基磺酰胺乙酸(N-Et FOSAA)广泛存在于活性污泥和污泥施用土壤中[1]。N-Et FOSAA的降解是环境中全氟辛基磺酸(PFOS)的重要来源。本实验探究了温室土培条件下,玉米、大豆、绿豆、水萝卜、黑麦草、苜蓿和生菜七种植物对N-Et FOSAA的吸收和传输,以及N-Et FOSAA在土壤-植物系统中降解。我们在七种植物根中均检测到N-Et FOSAA;在植物的根、茎、叶以及种植植物的土壤中检测到N-Et FOSAA的四种降解产物:包括N-乙基全氟辛基磺酰胺(N-Et FOSA)、全氟辛基磺酰胺(FOSA)、全氟辛基磺酰胺乙酸(FOSAA)和PFOS。N-Et FOSAA的降解动力学符合一级反应动力学方程,土壤-植物系统中N-Et FOSAA的降解速率为0.063-0.165 d-1,与无植物存在的土壤中的降解速率相比,植物的种植使N-Et FOSAA的降解速率快1.40-3.6倍。
N-ethyl perfluorooctanesulfonamido acetic acid(N-Et FOSAA) has been found extensively in sewage sludge and sludge-amended soils.The degradation of N-Et FOSAA serves as a significant source of perfluorooctanesulfonate(PFOS) in the environment.In this study,the uptake,translocation of N-Et FOSAA in seven species of plants,namely maize,soy bean,mung bean,radish,ryegrass,alfalfa and lettuce,and the degradation of N-Et FOSAA in soil-plant microcosms were evaluated over 60 days.N-Et FOSAA was found in the roots of all plant species studied.Four degradation products,including N-Ethyl perfluorooctane sulfonamide(N-Et FOSA),perfluorooctane sulfonamide(FOSA),perfluorooctane sulfonamide acetate(FOSAA) and PFOS were found in the soils and plant roots,stems and leaves,indicating the degradation of N-Et FOSAA in soil-plant system.Degradation kinetics fitted first-order kinetic model well.In the presence of plants,degradation rates of N-Et FOSAA ranged of 0.063-0.165 d-1,which was 1.40-3.6 times higher than those in the absence of plants.
引文
[1]Sepulvado,J.G.,Blaine,A.C.,Hundal,L.S.,Higgins,C.P.Environ.Sci.Technol.2011,45:8106.