Chlorpyrifos formulations

1. Chemical Composition and Properties:

Active Ingredient: Chlorpyrifos is a broad-spectrum organophosphate insecticide. It is a neurotoxin that inhibits the enzyme acetylcholinesterase, affecting nerve function in pests.

2. Formulations:

1. Chlorpyrifos 01.50% DP:

• Formulation Type: Dustable Powder (DP) with 1.50% active ingredient.
• Appearance: Fine, white to off-white powder.
• Solubility: Insoluble in water, soluble in organic solvents.

2. Chlorpyrifos 10% Granules:

• Formulation Type: Granular Formulation with 10% active ingredient.
• Appearance: Granules.
• Solubility: Insoluble in water; released into soil after application.

3. Chlorpyrifos 20% EC:

• Formulation Type: Emulsifiable Concentrate (EC) with 20% active ingredient.
• Appearance: Amber-colored liquid.
• Solubility: Forms an emulsion when diluted with water.

4. Chlorpyrifos 50% EC:

• Formulation Type: Emulsifiable Concentrate (EC) with 50% active ingredient.
• Appearance: Amber liquid.
• Solubility: Forms a stable emulsion in water.

5. Chlorpyrifos 02% w/w EC:

• Formulation Type: Emulsifiable Concentrate (EC) with 2% active ingredient.
• Appearance: Yellow to amber liquid.
• Solubility: Soluble in organic solvents.

6. Chlorpyrifos 75% w/w WG:

• Formulation Type: Water Dispersible Granules (WG) with 75% active ingredient.
• Appearance: White or light yellowish powder that disperses in water.

7. Chlorpyrifos 19% ME:

• Formulation Type: Microemulsion (ME) with 19% active ingredient.
• Appearance: Clear liquid, highly stable emulsion.
• Solubility: Forms a microemulsion with water.

3. Mode of Action:

• Mechanism: Chlorpyrifos acts as a neurotoxin. It inhibits acetylcholinesterase (AChE), an enzyme necessary for proper nerve function in insects. The inhibition of AChE leads to the accumulation of acetylcholine in the synaptic clefts, causing continuous nerve transmission, paralysis, and ultimately the death of the pest.

4. Target Pests:

Chlorpyrifos is effective against a wide range of pests, including:

• Insects:

1. Aphids

2. Caterpillars (e.g., Lepidoptera larvae)

3. Termites

4. Whiteflies

5. Mosquitoes

6. Moths

7. Weevils

8. Fleas

9. Ants

10. Cockroaches

11. Ticks

• Nematodes and Other Soil Pests: Chlorpyrifos is commonly used to control soil-borne pests in agriculture.

5. Application on Crops:

• Crops Treated: Chlorpyrifos is applied to a broad range of crops, including:

1. Cotton

2. Cereals (e.g., wheat, rice, maize)

3. Vegetables (e.g., tomatoes, cucumbers, peppers)

4. Fruits (e.g., citrus, apples)

5. Tobacco

6. Potatoes

7. Soybean

8. Alfalfa

• Dosage: The dosage for Chlorpyrifos varies by formulation:

1. Chlorpyrifos 01.50% DP: Typically used at a rate of 5-10 kg per hectare for soil applications.

2. Chlorpyrifos 10% Granules: Generally applied at 15-20 kg per hectare.

3. Chlorpyrifos 20% EC: Typically applied at 0.5-1.5 L per hectare.

4. Chlorpyrifos 50% EC: Applied at 0.2-1.0 L per hectare.

5. Chlorpyrifos 02% EC: Used at 1-3 L per hectare.

6. Chlorpyrifos 75% WG: Application rate typically 50-100 g per hectare.

7. Chlorpyrifos 19% ME: Applied at 0.5-1.0 L per hectare.

• Spray Timing:

• Apply early morning or late evening to avoid excessive evaporation and minimize harm to beneficial insects.
• Application timing depends on pest infestation levels and crop type. For soil pests, apply before planting or early in the growing season.

6. Features and Benefits:

• Selective Action: Chlorpyrifos is effective against a broad spectrum of pests, but it may affect non-target organisms if not used correctly. It is highly toxic to aquatic organisms and should be applied with caution.
• Long Residual Activity: Chlorpyrifos provides long-lasting pest control, often lasting up to 4 weeks or more, depending on the formulation.
• Low Resistance Risk: Although there are instances of resistance in some pests, the risk of resistance is generally moderate due to the neurotoxic mode of action. For effective resistance management, it is important to rotate with other insecticides.
• Environmental Compatibility: Chlorpyrifos is highly toxic to aquatic life and bees, so extreme caution is required around water sources and when applied in pollinator-active areas. The product can persist in the environment, especially in water and soil.

7. Precautions During Use:

• Toxicity: Chlorpyrifos is classified as moderately toxic to humans (Toxicity Category III). Prolonged exposure or large amounts can cause neurotoxic effects, including headaches, dizziness, nausea, and in severe cases, respiratory failure.
• Protective Measures:

• Always wear protective clothing, gloves, goggles, and a respirator when applying the product.
• Avoid direct contact with the skin and eyes.
• Ensure adequate ventilation when handling and applying the product.

• Environmental Safety: Chlorpyrifos should not be applied near waterways, as it is highly toxic to fish and aquatic organisms. Also, care should be taken to avoid runoff into non-target areas.

8. Waiting Period (Pre-harvest Interval):

• Depends on the crop and regional regulations: The Pre-Harvest Interval (PHI) varies by crop, typically between 7-30 days. Refer to the product label for specific intervals based on the crop being treated.

9. Storage and Handling:

• Storage: Store in a cool, dry, and ventilated area. Chlorpyrifos should be kept in its original container and away from heat, moisture, and sunlight. Keep out of reach of children.
• Handling: Handle with caution, ensuring that protective gear is worn. Follow all safety instructions on the product label for mixing and application.

10. Toxicology and First Aid:

• Symptoms of Exposure:

1. Inhalation: Difficulty breathing, dizziness, and nausea.

2. Skin Contact: Irritation, redness, or rash.

3. Eye Contact: Severe irritation, redness, or burning.

4. Ingestion: Abdominal pain, dizziness, and vomiting.

• First Aid:

1. Skin Contact: Wash the area thoroughly with soap and water.

2. Eye Contact: Rinse immediately with water for 15-20 minutes.

3. Inhalation: Move to fresh air. Administer oxygen if necessary.

4. Ingestion: Do not induce vomiting; seek medical attention immediately.

• Antidote: There is no specific antidote. Atropine and pralidoxime may be used as part of the treatment for organophosphate poisoning.

11. Resistance Management:

• Chlorpyrifos should be used as part of an Integrated Pest Management (IPM) program to avoid overuse and minimize resistance. It is best to rotate with other insecticides that have different modes of action, such as pyrethroids or neonicotinoids.