ABSTRACT
This study explores the toxic effects of herbicide, Paraquat Dichloride on Zebrafish (Danio rerio), a commonly used model organism in toxicological research studies. These fish are often used in research because they are small, easy to handle, and react clearly to harmful substances. In this experiment, healthy adult zebrafish were kept in clean water and water mixed with the herbicide at three levels: 1 mg/L, 2 mg/L, and 3 mg/L. The fish were observed for 72 hours to check how many survived and how they behaved.
No fish died in clean water or at 1 mg/L, but many died at 2 mg/L, and all died at 3 mg/L.
So, LC₅₀ in 24 hrs is 3 mg/L, LC₁₀₀ in 72 hrs is 3 mg/L. LC₁₀₀ in 72 hrs is 1 mg/L, 2 mg/L, LOEC is 1 mg/L. Along with death, treated fish showed unusual behaviour like swimming alone, staying in dark areas for long, acting aggressively, and not swimming properly. These changes suggest the herbicide affected the fish’s brain or stress levels.
To know more, biochemical analysis was done on fish tissues. The results showed reduced levels of important enzymes like Hexokinase (reduced from 192.9 U/g to 38.5 U/g), glucose 6-phosphate (reduced from 32.1 mg/gm to 12.8 mg/gm), along with decline in Glycogen (reduced from 3.0 mg/gm to 1.2 mg/gm), protein (reduced from 0.2 mg/gm to 0.05 mg/gm) and cholesterol (reduced from 3.3 mg/gm to 1.3 mg/gm). This suggests disrupted metabolism and possible liver damage.
In short, this herbicide can harm fish in many ways—not just killing them but also causing serious changes in behaviour and health. This shows the need to use such chemicals more carefully to protect aquatic life.
This study explores the toxic effects of herbicide, Paraquat Dichloride on Zebrafish (Danio rerio), a commonly used model organism in toxicological research studies. These fish are often used in research because they are small, easy to handle, and react clearly to harmful substances. In this experiment, healthy adult zebrafish were kept in clean water and water mixed with the herbicide at three levels: 1 mg/L, 2 mg/L, and 3 mg/L. The fish were observed for 72 hours to check how many survived and how they behaved.
No fish died in clean water or at 1 mg/L, but many died at 2 mg/L, and all died at 3 mg/L.
So, LC₅₀ in 24 hrs is 3 mg/L, LC₁₀₀ in 72 hrs is 3 mg/L. LC₁₀₀ in 72 hrs is 1 mg/L, 2 mg/L, LOEC is 1 mg/L. Along with death, treated fish showed unusual behaviour like swimming alone, staying in dark areas for long, acting aggressively, and not swimming properly. These changes suggest the herbicide affected the fish’s brain or stress levels.
To know more, biochemical analysis was done on fish tissues. The results showed reduced levels of important enzymes like Hexokinase (reduced from 192.9 U/g to 38.5 U/g), glucose 6-phosphate (reduced from 32.1 mg/gm to 12.8 mg/gm), along with decline in Glycogen (reduced from 3.0 mg/gm to 1.2 mg/gm), protein (reduced from 0.2 mg/gm to 0.05 mg/gm) and cholesterol (reduced from 3.3 mg/gm to 1.3 mg/gm). This suggests disrupted metabolism and possible liver damage.
In short, this herbicide can harm fish in many ways—not just killing them but also causing serious changes in behaviour and health. This shows the need to use such chemicals more carefully to protect aquatic life.