title: Effects of 1,2,4-trichlorobenzene on the enzyme activities and ultrastructure of earthworm Eisenia fetida.
abstract: Adult Eisenia fetida earthworms were exposed to sub-lethal concentrations of 1,2,4-trichlorobenzene to assess the toxicity of contaminated soils. The LC₅₀ of 1,2,4-TCB at 7 and 14 d were 945±175 and 890±169 mg kg⁻¹. A lower dose of 1,2,4-TCB (25 mg g⁻¹) had stimulatory effects on SOD and AChE activities, but AChE activities were significantly inhibited at higher treatment levels (100 and 400 mg g⁻¹). SOD activities increased after 2, 7, and 14 d of exposure, but AChE activities were significantly inhibited at 400 mg/kg 1,2,4-TCB after 2, 7, and 14 d of exposure, and the inhibition rates were 25.41%, 28.65%, and 25.05%. Ultrastructural observation of the intestinal epithelium at three concentrations (control, 50, and 400 mg g⁻¹) revealed that the epicuticle, cuticle layer, and microvilli were damaged with increasing 1,2,4-TCB concentration. At 400 mg kg⁻¹, mitochondria were seriously injured and the smooth endoplasmic reticulum was seriously dilated.
authors.affiliation: College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, People's Republic of China.
authors.forename: Shi-jin
authors.initials: SJ
authors.lastname: Wu
authors.forename: Huaxing
authors.initials: H
authors.lastname: Zhang
authors.forename: Yan
authors.initials: Y
authors.lastname: Hu
authors.forename: Hui-long
authors.initials: HL
authors.lastname: Li
authors.forename: Jian-meng
authors.initials: JM
authors.lastname: Chen
mesh_terms: D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D002722:Chlorobenzenes / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D007928:Lethal Dose 50; D009835:Oligochaeta / Q000187:drug effects* / Q000201:enzymology / Q000648:ultrastructure; D012989:Soil Pollutants / Q000633:toxicity*; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D002722:Chlorobenzenes; D012989:Soil Pollutants; C009947:1,2,4-trichlorobenzene; D013482:Superoxide Dismutase; D000110:Acetylcholinesterase