title: Bioavailability assessment of thiacloprid in soil as affected by biochar.
abstract: Biochars can significantly sorb pesticides, and reduce their bioavailability in agricultural soils. In this study, the effects of a type of biochar (BC500) on the sorption, degradation, bioaccumulation and bioavailability of thiacloprid, which is a commonly used insecticide, were investigated. The thiacloprid sorption constant (Kfvalues) increased by 14 times after 2% BC500 application, and the degradation of the insecticide decreased with increasing amounts of the biochars in the soil. Coupled with the exhaustive extraction and single-point Tenax method, the bioavailability of thiacloprid was predicted in the presence of the biochar. In soils amended with BC500, the thiacloprid concentrations accumulated in Tenax correlated well with those observed in earthworms (R2= 0.887), whereas the concentrations extracted by exhaustive method followed a less significant relationship with those in earthworms (R2= 0.624). The results of Tenax extractions and earthworm bioassays indicate that biochar reduces the bioavailability of thiacloprid in soil, but the delayed degradation and increased earthworm accumulation in aged biochar-amended soil imply that the environmental risks of biochar application to earthworms remain.
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, PR China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Li
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, PR China.
authors.forename: Yulong
authors.initials: Y
authors.lastname: Zhu
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, PR China. Electronic address: xingangliu@caas.cn.
authors.forename: Xingang
authors.initials: X
authors.lastname: Liu
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, PR China.
authors.forename: Xiaohu
authors.initials: X
authors.lastname: Wu
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, PR China.
authors.forename: Fengshou
authors.initials: F
authors.lastname: Dong
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, PR China.
authors.forename: Jun
authors.initials: J
authors.lastname: Xu
authors.affiliation: State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, 100193, PR China. Electronic address: zhengyongquan@ippcaas.cn.
authors.forename: Yongquan
authors.initials: Y
authors.lastname: Zheng
mesh_terms: D000383:Agriculture; D000818:Animals; D001682:Biological Availability; D002606:Charcoal / Q000737:chemistry*; D004777:Environment; D000073943:Neonicotinoids; D009835:Oligochaeta / Q000378:metabolism*; D011725:Pyridines / Q000737:chemistry / Q000378:metabolism*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000737:chemistry / Q000378:metabolism*; D013843:Thiazines / Q000737:chemistry / Q000378:metabolism*
chemical_list: D000073943:Neonicotinoids; D011725:Pyridines; D012987:Soil; D012989:Soil Pollutants; D013843:Thiazines; C540010:biochar; D002606:Charcoal; C417209:thiacloprid
keywords: Bioavailability; Biochar; Earthworm; Tenax method; Thiacloprid