Fonofos

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Fonofos is an organophosphate insecticide and nematicide that was widely used in agriculture to control soil-borne pests. It is known for its effectiveness in managing a variety of insects and nematodes that affect crops such as corn, soybeans, and potatoes. However, due to its high toxicity and potential environmental impact, its use has been restricted or banned in many countries.

Chemical Properties

Fonofos, chemically known as O-Ethyl S-phenyl ethylphosphonodithioate, is an organophosphate compound. It is a yellow to amber liquid with a distinct odor. The chemical formula for fonofos is C₁₀H₁₅OPS₂.

Mode of Action

Fonofos works by inhibiting the enzyme acetylcholinesterase, which is essential for the proper functioning of the nervous system in insects. This inhibition leads to an accumulation of acetylcholine at nerve synapses, causing continuous nerve impulse transmission, paralysis, and eventually death of the pest.

Usage

Fonofos was primarily used in soil treatment to protect crops from root-feeding insects and nematodes. It was applied in granular form or as an emulsifiable concentrate. The application was typically done at planting time or as a pre-plant treatment.

Environmental and Health Concerns

Due to its high toxicity, fonofos poses significant risks to human health and the environment. It is highly toxic to birds, fish, and other wildlife. Human exposure to fonofos can occur through inhalation, ingestion, or skin contact, leading to symptoms such as headaches, dizziness, nausea, and in severe cases, respiratory failure and death.

Regulation and Ban

Due to its adverse effects, fonofos has been banned or restricted in many countries. In the United States, the Environmental Protection Agency (EPA) has classified fonofos as a restricted-use pesticide, meaning it can only be applied by certified applicators.

Related Pages

• Organophosphate
• Insecticide
• Nematicide
• Acetylcholinesterase
• Environmental Protection Agency