The toxic mechanism of high lethality of herbicide butachlor in marine flatfish flounder, Paralichthys olivaceus

Abstract

The toxic mechanism of herbicide butachlor to induce extremely high lethality in marine flatfish flounder, Paralichthys Olivaceus, was analyzed by histopathological examination, antioxidant enzymes activities and ATP content assay. Histopathological examination of gill, liver and kidney of exposed fishes showed that gill was a target organ of butachlor. The butachlor seriously impaired the respiration of gills by a series of lesions such as edema, lifting and detachment of lamellar epithelium, breakdown of pillar cells, and blood congestion. The dysfunction of gill respiration caused suffocation to the exposed flounder with extremely high acute lethality. Antioxidant enzyme activity assay of the in vitro cultured flounder gill (FG) cells exposed to butachlor indicated that butachlor markedly inhibited the antioxidant enzyme activities of Superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX). Furthermore, along with the decline of antioxidant enzyme activities, ATP content in the exposed FG cells decreased, too. This infers that the oxidative stress induced by butachlor can inhibit the production of cellular ATP. Similar decrease of ATP content was also observed in the exposed flounder gill tissues. Taken together, as in FG cells, butachlor possibly induced a short supply of ATP in pillar cells by inhibiting the antioxidant enzyme activities and then affecting the contractibility of the pillar cells, which in turn resulted in the blood congestion and suffocation of exposed flounder.

Histopathological and haematological response of male rainbow trout (Oncorhynchus mykiss) subjected to butachlor

“…Our results show that the kidneys of rainbow trout can be damaged by toxic concentrations of butachlor. However, in contrast to our study, Guo et al ( 2010) found that acute exposure to butachlor induced a marked dysfunction in gills, but not the liver and kidneys of flounder (Paralichthys olivaceus).…”

“…The remnants of the pesticide can enter ground waters used for human consumption and thus can be potentially hazardous for human health (Yu et al 2003). The severe effects of the herbicide on many animals have been reported and include retardation of growth and reproduction in earthworms (Eisenia fetida) (Muthukaruppan and Gunasekaran 2010), damage to epithelial tissue in E. fetida (Muthukaruppan et al 2005), neurotoxicity in land snails (Rajyalakshmi et al 1996), genotoxicity in toads, frog tadpoles and fishes (Ateeq et al 2006;Yin et al 2008;Guo et al 2010), while it acts as an indirect mutagen in hamsters and rats (Hsu et al 2005). The 96h LC 50 for the acute toxicity of butachlor in fish varies from 0.14 to 0.52 mg/l and its rate for rainbow trout (Oncorhynchus mykiss) has been reported to be 0.52 mg/l, showing its high toxicity in fish (Tomlin 1994).…”

Preparation and Characterization of Butachlor/(2-Hydroxypropyl)-β-cyclodextrin Inclusion Complex: Improve Soil Mobility and Herbicidal Activity and Decrease Fish Toxicity

“…One of the reasons for this might be due to the barrier function formed by the complexation between HP-β-CD and butachlor. The mechanisms of butachlor on fish mainly including the dysfunction of gill respiration, the generation of oxidative stress, and biochemical alterations . Many studies in the literature have reported the sustained release characteristics of inclusion complex concerning CDs. , In butachlor/HP-β-CD inclusion complex and butachlor technical exposure groups, the concentration of free butachlor in the former group was lower, so tested fishes contacted less butachlor.…”

“…One of the reasons for this might be due to the barrier function formed by the complexation between HP-β-CD and butachlor. The mechanisms of butachlor on fish mainly including the dysfunction of gill respiration, the generation of oxidative stress, 43 and biochemical alterations. 10 Many studies in the literature have reported the sustained release characteristics of inclusion complex concerning CDs.…”

Boule gene expression underpins the meiotic arrest in spermatogenesis in male rainbow trout ( Oncorhynchus mykiss ) exposed to DEHP and butachlor

“…LC 50 (96 h) of butachlor in fishes has been reported to range from 0.14 to 0.52 mg/L (0.52 mg/L in rainbow trout, Oncorhynchus mykiss (Tomlin, 1994). Many adverse effects of this herbicide on fish species have been reported (Lasheidani et al, 2008;Guo et al, 2010;Tu et al, 2013;Zhu et al, 2014;Xu et al, 2015).…”