Fenthion is described as a toxicant hazardous to which of the following?

Fenthion is described as a toxicant hazardous to which of the following?

• A. Only birds
• B. All birds and all animals including humans
• C. Only mammals
• D. Only pests

Answer: (B)

Fenthion’s hazard comes from its action as an organophosphate insecticide that inhibits acetylcholinesterase, the enzyme that breaks down acetylcholine in nerve junctions. When this enzyme is blocked, nerve signals linger, leading to overstimulation of the nervous system. This effect is not limited to pests; it can affect a wide range of vertebrates, including birds, mammals, and humans. That broad toxicity is why fenthion is described as hazardous to all birds and all animals including humans, not just to pests.

Fenthion’s hazard comes from its action as an organophosphate insecticide that inhibits acetylcholinesterase, the enzyme that breaks down acetylcholine in nerve junctions. When this enzyme is blocked, nerve signals linger, leading to overstimulation of the nervous system. This effect is not limited to pests; it can affect a wide range of vertebrates, including birds, mammals, and humans. That broad toxicity is why fenthion is described as hazardous to all birds and all animals including humans, not just to pests.