Bioaccumulation, Metabolism and the Toxic Effects of Chlorfenapyr in Zebrafish (Danio rerio)

Abstract

Chlorfenapyr is widely used as an insecticide/miticide. Tralopyril, the active metabolite of chlorfenapyr, is used as an antifouling biocide in antifouling systems, and negatively affects aquatic environments. However, it is unclear whether tralopyril is a metabolite of chlorfenapyr in aquatic vertebrates, and there is little data on the bioaccumulation and toxicity of chlorfenapyr to aquatic vertebrates. In this study, the bioaccumulation and elimination of chlorfenapyr in zebrafish were assessed, and tralopyril, the active metabolite of chlorfenapyr, was determined. The effects of chronic exposure to chlorfenapyr on zebrafish liver and brain oxidative damage, apoptosis, immune response, and metabolome were investigated. These results showed that chlorfenapyr has a high bioaccumulation in zebrafish, with bioaccumulation factors of 864.6 and 1321.9 after exposure to 1.0 and 10 μg/L chlorfenapyr for 21 days, respectively. Chlorfenapyr at these concentrations also rapidly accumulated in zebrafish, reaching 615.5 and 10336 μg/kg on the second and third days of exposure, respectively. Chlorfenapyr was degraded to tralopyril in zebrafish; therefore, both chlorfenapyr and tralopyril should be considered when evaluating the risk of chlorfenapyr to aquatic organisms. In addition, chronic exposure caused oxidative damage, apoptosis, and immune disorders in zebrafish liver. Chronic exposure also altered the levels of endogenous metabolites in liver and brain. After 9 days of depuration, some indicators of oxidative damage, apoptosis, and immunity returned to normal levels, but the concentration of endogenous metabolites in zebrafish liver was still altered. Overall, these results provide useful information for evaluating the toxicity and environmental fate of chlorfenapyr in aquatic vertebrates.

Pesticides Exposure-Induced Changes in Brain Metabolome: Implications in the Pathogenesis of Neurodegenerative Disorders

“…A group of pregnant rats exposed to a mixture of pesticides showed decreased levels of amino acids like glutamine, serine, lysine, and ethanolamine in the brain, indicating altered the amino acid metabolites (Bonvallot et al 2018 ). Chlorfenapyr-treated zebrafish brain metabolome revealed a significant decrease in the metabolites like lysine, alanine, tyrosine, leucine, phenylalanine, and valine, while 7-methylxanthine and taurine were shown to be upregulated (Chen et al 2021 ). Dichlorvos-poisoned broilers showed variations in amino acids like gamma-glutamylcysteine, glutathione disulfide, and dipeptide compound (Huang et al 2022 ).…”

Unravelling the Polytoxicology of Chlorfenapyr on Non-Target HepG2 Cells: The Involvement of Mitochondria-Mediated Programmed Cell Death and DNA Damage

“…The degradation of CHL in soil, sediment, and water is slow, with an average half-life of 1.0 year, 1.1 years, and 0.8 years, respectively. Moreover, the toxic effects of CHL have been reported in ducks, fish, silkworm, and mice [ 3 , 4 , 5 , 6 ]. Due to its high environmental persistence and potential toxic effects on non-target organisms, CHL has been banned or limited to use in the Europe and United States [ 4 ].…”

“…Moreover, the toxic effects of CHL have been reported in ducks, fish, silkworm, and mice [ 3 , 4 , 5 , 6 ]. Due to its high environmental persistence and potential toxic effects on non-target organisms, CHL has been banned or limited to use in the Europe and United States [ 4 ]. As for humans, a few cases of fatal toxicity of CHL have also been reported.…”

Mitochondria-targeted nanocarriers doubled the toxicity of oxidative phosphorylation and ATP synthesis disruptive insecticides against Spodoptera frugiperda

“…[10][11][12] It has no crossresistance to other classes of insecticides and is used in several countries. 13 Chl disrupts steps in the bioconversion pathway of adenosine triphosphate (ATP) from adenosine diphosphate (ADP) in mitochondria, 14 thus causing energy loss and subsequent death of the organism. 14 In China, Chl has been recommended for the control of the global pest S. frugiperda.…”

“…[17][18][19] For example, chronic exposure to Chl can cause oxidative damage, apoptosis, and immune disorders in zebrafish liver. 13,20 Moreover, cases of dog deaths due to acute Chl toxicity have been reported. 21 Some researchers have developed functional nanocarriers for Chl to improve its efficiency.…”