Toxic effects of an organophosphate pesticide, envoy 50 SC on the histopathological, hematological, and brain acetylcholinesterase activities in stinging catfish (Heteropneustes fossilis)

Abstract

Background: Freshwater fish in Bangladesh are adversely affected by the washed off pesticides, used in agriculture. The aim of this study was to evaluate the impacts of a commonly used organophosphate pesticide on freshwater stinging catfish, Heteropneustes fossilis, which envisioned that the possible threats might occur by this organophosphate group to other species in the wild. Methodology: To study the potential hazards of Envoy 50 SC on H. fossilis, fry of the fish were exposed to the acute toxicity tests. Changes in the hematological parameters, organ-specific histomorphologies, and brain acetylcholinesterase (AChE) activities were determined by treating the fish with agricultural recommended dose and below that dose of 0.015 and 0.0075 ppm, respectively. Results: LC 50 of Envoy 50 SC for the fish was determined as 0.151 (0.014-0.198) ppm. Pesticide abruptly altered the normal tissue structures of the gill, liver, and kidney. The major alterations included were the gill lamellae missing, gill clubbing, hyperplasia, nuclear hypertrophy, vacuolation, glomerular expansion, increasing diameter of the renal tubules, hemorrhage, necrosis, and pyknosis. In blood cells, changes observed in the peripheral nuclear erythrocyte were large lymphocyte, dead cell, fusion of the cells, binucleated cells, tear-shaped cells, ghost cells, senile cells, and abnormal structures of the cells. Significantly lower (P < 0.05) red blood cell (RBC) count and AChE activities in fish brain due to the pesticide exposure suggested the reasons of abrupt behavior, increased oxygen consumption, and fish mortality at higher concentration of this organophosphate pesticide. Conclusion: The presence of pesticides, even at low concentrations, caused deleterious effects on the earlier life stages of a comparatively harder and robust fish, suggesting a wider range effect on the more sensitive wild life, in particular decrease in survival in their native environment. Therefore, measures should be taken to minimize the risk of contamination of the aquatic environment by such toxic chemicals.

Zebrafish as a suitable model for studying the mode of action and harmfulness of organophosphate pesticides

“…In particular, profenofos exposure (60 µgL -1 ) during 60 days caused prominent AChE inhibition in the brain of Labeo rohita [28]. A sublethal exposure of Astyanax aeneus (Characidae) and stinging catfish Heteropneustes fossilis to ethoprophos and Envoy 50 SC correspondingly caused a significant reduction of brain cholinesterase activity [29,30]. However, in the present study the inhibitory effect of studied organophosphate was appeared in case of chronic exposure rather than acute exposure.…”

Nephroprotective effect of Emblica officinalis fruit extract against malachite green toxicity in piscine model: Ultrastructure and oxidative stress study

“…Exposure to MG developed nephrotoxicity in fish evidenced by both histopathological and ultrastructural studies. Degenerative cytoplasmic changes, desquamation, and vacuolation of tubules substantiated the toxicity of MG. Cytoplasmic and degenerative changes in brush‐border manifested in luminal enlargement and conversely shrunken glomeruli were also reported in the renal tissue of Gobiocypris rarus and Heteropneustes fossilis exposed to atrazine and pesticide respectively (Akter et al, 2020; Yang, Zha, Li, Li, & Wang, 2010). Observed dilation of blood vessels and hyperemia in glomerulus corroborated inflammation of glomerulus, glomerulonephritis (Benli, Köksal, & Ozkul, 2008; Silva & Martinez, 2007).…”

“…Observed dilation of blood vessels and hyperemia in glomerulus corroborated inflammation of glomerulus, glomerulonephritis (Benli, Köksal, & Ozkul, 2008; Silva & Martinez, 2007). Concurrent nuclear alterations in form of pyknosis and karyorrhexis were also reported in the kidney of H. fossilis and Labeo rohita exposed to organophosphate pesticide (Akter et al, 2020; Hussain et al, 2019). The occurrence of luminal occlusion may be accredited to the swelling of epithelial cells, interfering with the movement of fluid through it and slowing down the reabsorption and secretion process (Hinton & Lauren, 1990; Meyers & Hendricks, 1985; Takashima & Hibiya, 1995).…”

Heavy metal toxicity in Buriganga river alters the immunology of Nile tilapia (Oreochromis niloticus L)

“…Among the aquatic organisms, fish is an experimental model, which is used as an important bio-indicators of potential risks of contamination with toxicants in the aquatic water body [9,10,11]. The changes in the behavior of fishes are used as biomarkers in the polluted aquatic environment [12,13].…”