Azoxystrobin induced genotoxicity in Pethia conchonius, a freshwater fish of river Teesta, India

Azoxystrobin, a widely used fungicide, can contaminate water bodies through surface run-off, posing a risk to aquatic organisms. This study aimed to assess the genotoxic effects of azoxystrobin on the fish Pethia conchonius. The 96 h lethal concentration (LC₅₀) of azoxystrobin was determined to be 0.514 mg/L. Based on LC_50, three sub-lethal concentrations (SLCs) of 0.025 mg/L, 0.0514 mg/L, and 0.103 mg/L were used to expose fish for 96 h. The blood and gill samples were collected at 24 h intervals for analysis. The Micronucleus (MN) and Comet assays were used to evaluate nuclear abnormalities and DNA damage, respectively. The results showed that the frequency of nuclear abnormalities and DNA damage in the exposed groups was significantly higher than the control, with increasing concentrations and duration of exposure. The highest levels of micronuclei, notched and blebbed nuclei, and DNA damage parameters were observed in the group exposed to SLC III for 96 h. These findings indicate that azoxystrobin is highly genotoxic to fish causing severe DNA damage.