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Patrick Riefer Timm Klausmeyer Andreas SchäFfer Jan Schwarzbauer Burkhard Schmidt 《Journal of environmental science and health. Part. B》2013,48(5):394-403
Anthropogenic contaminants like nonylphenols (NP) are added to soil, for instance if sewage-sludge is used as fertilizer in agriculture. A commercial mixture of NP consists of more than 20 isomers. For our study, we used one of the predominate isomers of NP mixtures, 4-(3,5-dimethylhept-3-yl)phenol, as a representative compound. The aim was to investigate the fate and distribution of the isomer within soil and soil derived organo-clay complexes. Therefore, 14C- and 13C-labeled NP was added to soil samples and incubated up to 180 days. Mineralization was measured and soil samples were fractionated into sand, silt and clay; the clay fraction was further separated in humic acids, fulvic acids and humin. The organo-clay complexes pre-incubated for 90 or 180 days were re-incubated with fresh soil for 180 days, to study the potential of re-mobilization of incorporated residues. The predominate incorporation sites of the nonylphenol isomer in soil were the organo-clay complexes. After 180 days of incubation, 22 % of the applied 14C was mineralized. The bioavailable, water extractable portion was low (9 % of applied 14C) and remained constant during the entire incubation period, which could be explained by an incorporation/release equilibrium. Separation of organo-clay complexes, after extraction with solvents to release weakly incorporated, bioaccessible portions, showed that non-extractable residues (NER) were preferentially located in the humic acid fraction, which was regarded as an effect of the chemical composition of this fraction. Generally, 27 % of applied 14C was incorporated into organo-clay complexes as NER, whereas 9 % of applied 14C was bioaccessible after 180 days of incubation. The re-mobilization experiments showed on the one hand, a decrease of the bioavailability of the nonylphenol residues due to stronger incorporation, when the pre-incubation period was increased from 90 to 180 days. On the other hand, a shift of these residues from the clay fraction to other soil fractions was observed, implying a dynamic behavior of incorporated residues, which may result in bioaccessibility of the NER of nonylphenol. 相似文献
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Pan Yongchun She Dongli Chen Xinyi Xia Yongqiu Timm Luís Carlos 《Environmental science and pollution research international》2021,28(31):41712-41725
Environmental Science and Pollution Research - Denitrification and NH3 volatilization are the main removal processes of nitrogen in coastal saline soils. In this incubation study, the effects of... 相似文献
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Rapid incorporation and short-term distribution of a nonylphenol isomer and the herbicide MCPA in soil-derived organo-clay complexes 总被引:1,自引:0,他引:1
Patrick Riefer Timm Klausmeyer Jan Schwarzbauer Andreas Sch?ffer Burkhard Schmidt Phillipe F. X. Corvini 《Environmental Chemistry Letters》2011,9(3):411-415
Organo-clay complexes in soil are a major sink for xenobiotics and, thus, often enhance their persistence dramatically. However,
the knowledge on environmental processes of non-extractable residue formation on a short time scale is very restricted. Therefore,
this study examined the distribution of 4-(3,5-dimethylhept-3-yl)phenol (NP) and 4-chloro-2-methylphenoxyacetic acid (MCPA)
in soil over a short time period of 48 h and in different soil sub-fractions. The overall proportion of organo-clay-associated
bound residues was not only abundant but also in the same range for both substances (MCPA: 8%; NP: 11% of applied 14C-radioactivity). However, a more detailed view revealed two different distribution patterns: a higher proportion of clay-associated
NP was accompanied by a lower content of bound residues, whereas a smaller fraction of clay-associated MCPA was characterized
by a higher proportion of non-extractable residues. Further on, a selective accumulation of bound residues among clay-associated
humic fractions was observed. NP residues were linked predominantly to humic acids, whereas MCPA residues tended to be incorporated
more into fulvic acids. It was evident that the overall distribution was influenced primarily by the physico-chemical properties
of the contaminants. This study demonstrates in detail a rapid initial incorporation accompanied by a specific distribution
into soil sub-fractions for selected xenobiotics in soil and points to a complex interaction of clay-associated organic matter
with low molecular weight compounds. 相似文献
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