Chronic toxicity of commercial chlorpyrifos to earthworm Pheretima peguana

Abstract

A chronic toxicity study was conducted in earthworms (Pheretima peguana) exposed to soil spiked with chlorpyrifos at concentrations of 0, 0.1, 1, 10, and 100 mg/kg soil dry matter for 7, 14, and 28 days. The integrity of the coelomocyte lysosomal membrane, nervous system, and male reproductive tissue was monitored using, respectively, the neutral-red retention assay, acetylcholinesterase (AChE) enzyme assay, and histomorphology of spermatogenic cells in the seminal vesicles and cocoon production (at 28 days after 28 days' exposure). Chlorpyrifos decreased the coelomocyte neutral-red retention time (NRRT) significantly (p < 0.05) at concentrations > 0.1 mg/kg soil as early as day 7 of exposure and was dose- and time-dependent. Chlorpyrifos inhibition of AChE activity was greater at day 7 than at day14 (p < 0.05) indicating possibly nerve recovery. Chlorpyrifos induced concentration-dependent damage to spermatogenic cells and cytophores in premature stages. The number and size of premature, maturing, and fully mature spermatogenic stages were increased at low concentrations (<1 mg/kg) but a number of these maturation stages declined at higher concentrations (10 and100 mg/kg) on day 28. The most severe effects were observed in the maturing and fully mature stages at the highest chlorpyrifos concentration, and this had an adverse impact on cocoon production and cocoon viability. Collectively, the results suggest induction of widespread effects on multiple organ systems in P. peguana exposed to chlorpyrifos. Although NRRT and AChE activity were the most sensitive of the biomarkers, cocoon production and cocoon viability could still be considered as diagnostic tools for monitoring effects from low-dose long-term chlorpyrifos toxicity and for evaluating population effects. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1450-1459, 2016.

Assessment of acute toxicity and biochemical responses to chlorpyrifos, cypermethrin and their combination exposed earthworm, Eudrilus eugeniae

“…Present study shows that paper contact toxicity of pesticides through skin of Eudrilus eugeniae, increases with the increase in pesticide concentrations. The LC 50 value of chlorpyrifos and cypermethrin for 48 h treatment period in different species of earthworms have been reported as follows: For CPF, 3.2 μg/cm 2 for Eisenia fetida [34], 14.19 μg/cm 2 for Eisenia fetida [35] and for cypermethrin: 10.63 μg/cm 2 for Eisenia fetida [35], 0.35 μg/cm 2 for Pheretima peguana [36], 0.30 μg/cm 2 for Metaphire posthuma and 3.84 μg/cm 2 for Eisenia fetida [37]. While LC 50 value for a combination of various pesticides in different earthworm species have been reported as follows: 6931.1 mg/ L of Butachlor + Chlorpyrifos mixture and 3699.3 mg/ L of Imidacloprid + Chlorpyrifos for Eisenia fetida [38], 35.06 mg/kg of Chlorpyrifos and cypermethrin mixture for Eisenia fetida andrei [39].…”

Antioxidant defense system responses, lysosomal membrane stability and DNA damage in earthworms (Eisenia fetida) exposed to perfluorooctanoic acid: an integrated biomarker approach to evaluating toxicity

“…Therefore, lysosomal membrane stability is regarded as a useful biomarker of subcellular level for the action of toxicants, and NRRT assay has been proved to be reliable, dose-related, and practical in assessing the adverse effects of environmental pollution by using various earthworm species. [73][74][75] The reduced NRRT value suggested that exposure stress has caused actual damages on lysosomal membrane of the organisms. 34 In this study, the NRRT values decreased with increasing PFOA concentration during the entire exposure period, suggesting that the retention time of lysosomal staining could indicate the toxic effects of PFOA on earthworms.…”

Enzymes of Earthworm as Indicators of Pesticide Pollution in Soil

“…Butachlor, Malathion and Carbofuran AChE When exposed to butachlor, no variation of AChE activity; on malathion exposure, maximum AChE inhibition (41% and 46%) after 9d and after 12d (54% and 62.9%) of carbofuran exposure [72] Pheretima peguana Chlorpyrifos AChE AChE acitivity is significantly inhibited (>60%) at two concentrations of pesticide [73] E. fetida andrei Benzo (a) pyrene AChE Increase in AChE acitivity [74] Eisenia fetida Carbofuran TChE Protein content and total cholinesterase activity increased in low level and vice-versa [75] Eisenia fetida…”