Enhanced reductive dechlorination of DDT in an anaerobic system of dissimilatory iron-reducing bacteria and iron oxide.
The transformation of DDT was studied in an anaerobic system of dissimilatory iron-reducing bacteria (Shewanella decolorationis S12) and iron oxide (alpha-FeOOH). The results showed that S. decolorationis could reduce DDT into DDD, and DDT transformation rate was accelerated by the presence of alpha-FeOOH. DDD was observed as the primary transformation product, which was demonstrated to be transformed in the abiotic system of Fe(2+)+alpha-FeOOH and the system of DIRB+alpha-FeOOH. The intermediates of DDMS and DBP were detected after 9 months, likely suggesting that reductive dechlorination was the main dechlorination pathway of DDT in the iron-reducing system. The enhanced reductive dechlorination of DDT was mainly due to biogenic Fe(II) sorbed on the surface of alpha-FeOOH, which can serve as a mediator for the transformation of DDT. This study demonstrated the important role of DIRB and iron oxide on DDT and DDD transformation under anaerobic iron-reducing environments.
Li
F B
FB
Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences, Guangzhou 510650, China. cefbli@soil.gd.cn
Li
X M
XM
Zhou
S G
SG
Zhuang
L
L
Cao
F
F
Huang
D Y
DY
Xu
W
W
Liu
T X
TX
Feng
C H
CH
D000693:Anaerobiosis; D001711:Biotransformation; D003634:DDT / Q000378:metabolism*; D003632:Dichlorodiphenyldichloroethane / Q000378:metabolism*; D005290:Ferric Compounds / Q000378:metabolism*; D007501:Iron / Q000378:metabolism*; D010084:Oxidation-Reduction; D020592:Shewanella / Q000378:metabolism*
D005290:Ferric Compounds; C000499:ferric oxide; D003634:DDT; D007501:Iron; D003632:Dichlorodiphenyldichloroethane