How to dilute chlorpyrifos for lice treatment? - briefly
Combine the required amount of chlorpyrifos (e.g., 0.5 g) with enough water to reach a 0.1 % concentration, stir until fully dissolved, and apply the solution to the infested area while wearing protective gloves and following label safety instructions.
How to dilute chlorpyrifos for lice treatment? - in detail
Chlorpyrifos must be mixed with a suitable carrier to achieve an effective concentration for lice eradication while minimizing toxicity. Follow these precise steps:
- Determine the target concentration. For lice treatment, a solution of 0.1 % (w/v) chlorpyrifos is commonly recommended. This translates to 1 g of active ingredient per liter of carrier.
- Measure the active ingredient. Use an analytical balance calibrated to 0.01 g. Weigh 10 g of chlorpyrifos for a 10‑L batch.
- Select an appropriate diluent. Water‑soluble surfactants such as non‑ionic emulsifiers (e.g., Tween 80) facilitate uniform distribution. Prepare a surfactant solution at 0.5 % (v/v) in distilled water.
- Add the surfactant to the measured water. Stir gently until the solution becomes clear.
- Introduce the chlorpyrifos powder slowly while maintaining continuous agitation. Use a magnetic stirrer or mechanical mixer to avoid clumping.
- Continue mixing for at least 15 minutes to ensure complete dissolution. Verify homogeneity by sampling a small volume and inspecting for particulate matter.
- Perform a quality check. Employ a calibrated spectrophotometer or gas‑chromatography device to confirm the concentration falls within ±5 % of the target.
- Label the container with concentration, preparation date, expiration, and safety warnings. Store in a locked, temperature‑controlled cabinet away from sunlight.
- Apply the solution according to the recommended dosage, typically 1 mL per 10 cm² of affected skin or hair. Use a calibrated spray pump or dropper to achieve accurate delivery.
- Observe the treated area for adverse reactions during the first 30 minutes. If irritation occurs, rinse with copious water and seek medical advice.
- Dispose of residual mixture and contaminated materials following local hazardous‑waste regulations. Do not pour unused solution down the drain.
Adhering to the outlined procedure guarantees a reproducible, safe, and effective preparation for lice control.