Application of modified attapulgite in phthalate acid ester-contaminated soil: Effects on phthalate acid ester dissipation and the composition of soil microbial community.
The effects of modified attapulgite (MA) on the dissipations of the plasticizers di-n-butyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) in soil, as well as on the composition of soil microbial community, were studied. DBP, DEHP (50 mg kg(-1) in soil, respectively), and MA (1, 5, and 10 % in soil) were mixed thoroughly with soil and incubated for 60 days. DBP- and DEHP-contaminated soils without MA were used as the controls. Both of DBP and DEHP residues in bulk soils and four soil fractions were measured at five incubation times 1, 7, 15, 30, and 60 days, and their dissipation kinetic equations were analyzed. The microbial phospholipid fatty acid (PLFA) concentrations were also measured at the end of experiment. Our results showed that the effect of modified attapulgite on DBP dissipation was related to its dosage in soil. The DEHP dissipation was both inhibited by MA at the 5 and 10 % rates in soils. The application of MA changed the content percentages but did not change the concentration order of phthalate acid esters (PAEs) in soil particle-size fractions. The total microbial PLFA content was significantly increased by 5 and 10 % MA in the contaminated soils. Meanwhile, the gram-negative (GN)/gram-positive (GP) ratios increased when MA was applied at the dosages of 5 and 10 % in DBP and 10 % in DEHP-contaminated soils. Principal component analysis (PCA) indicated that the change of bacteria PLFA, especially the GN bacterial PLFA, depended on the dosages of MA added into soil. The application of MA into soil has a positive effect on reducing the eco-toxicity of PAEs in soil based on the analysis of the soil microbial PLFA.
Life Science and Food Engineering School, Huaiyin Institute of Technology, Huai'an, 223001, Jiangsu, China. jgao@hyit.edu.cn.|Key Laboratory for Palygorskite Science and Applied Technology of Jiangsu Province, Huai'an, 223003, Jiangsu, China. jgao@hyit.edu.cn.
Jun
J
Gao
Faculty of Ideological and Political Theory, Huaiyin Institute of Technology, Huai'an, 223003, Jiangsu, China.
Yi-Ying
YY
Shi
Huaian Wanbang Aromatic Chemicals Industry Co., Ltd., Huai'an, Jiangsu, 223300, China.
Hai-Feng
HF
Zhou
Life Science and Food Engineering School, Huaiyin Institute of Technology, Huai'an, 223001, Jiangsu, China.|Key Laboratory for Palygorskite Science and Applied Technology of Jiangsu Province, Huai'an, 223003, Jiangsu, China.
Xu-Qin
XQ
Ren
Life Science and Food Engineering School, Huaiyin Institute of Technology, Huai'an, 223001, Jiangsu, China.
Huai
H
Ji
D052918:Environmental Restoration and Remediation / Q000379:methods*; D005227:Fatty Acids / Q000032:analysis; D017616:Magnesium Compounds / Q000737:chemistry*; D010743:Phospholipids / Q000032:analysis; D010795:Phthalic Acids / Q000737:chemistry*; D010968:Plasticizers / Q000737:chemistry; D017655:Silicon Compounds / Q000737:chemistry*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000737:chemistry*
D005227:Fatty Acids; D017616:Magnesium Compounds; D010743:Phospholipids; D010795:Phthalic Acids; D010968:Plasticizers; D017655:Silicon Compounds; D012989:Soil Pollutants; C032279:phthalic acid; C026325:attapulgite
Dissipation; Modified attapulgite; Phthalate acid ester (PAEs); Soil microbial community