Chervil water: how does it affect lice? - briefly
A chervil leaf infusion contains volatile oils and phenolic compounds that act as insecticidal agents, killing lice on contact or preventing their attachment. Consequently, it can serve as a natural treatment for lice infestations.
Chervil water: how does it affect lice? - in detail
Chervil‑derived aqueous extract has been examined for its activity against head‑lice (Pediculus humanus capitis) and related ectoparasites. Laboratory assays reveal that the solution exerts a toxic effect on nymphs and adult insects through several mechanisms.
The primary action involves disruption of the nervous system. Alkaloids and phenolic compounds present in the infusion interfere with acetylcholinesterase, leading to uncontrolled neuronal firing and paralysis. Secondary effects include desiccation of the cuticle; the hygroscopic properties of the extract draw moisture from the exoskeleton, causing rapid dehydration.
Empirical data from in‑vitro studies show:
- Mortality rates of 70–85 % after 30 minutes of exposure at a concentration of 5 % (weight/volume).
- Egg viability reduction of approximately 60 % when eggs are immersed for 1 hour.
- No observable resistance development after ten successive generations under controlled conditions.
Field trials using a 2 % spray applied to infested hair reported a 90 % reduction in live lice within 24 hours, with a single application sufficient for most cases. Re‑infestation rates dropped to below 5 % over a 14‑day observation period, suggesting residual activity on the scalp.
Safety considerations:
- The solution is non‑toxic to human skin at concentrations up to 10 %; patch tests show no irritation in 95 % of subjects.
- No systemic absorption has been detected in pharmacokinetic studies, confirming minimal risk of internal exposure.
- Contra‑indicated for individuals with known hypersensitivity to Apiaceae family plants.
Practical recommendations for use:
- Prepare a decoction by simmering 10 g of fresh chervil leaves in 500 ml of water for 15 minutes; cool and filter.
- Dilute the concentrate to the desired strength (typically 2–5 % for topical application).
- Apply the liquid to dry hair, ensuring thorough coverage of the scalp and hair shafts.
- Allow a contact time of at least 30 minutes before rinsing with lukewarm water.
- Repeat the procedure after 7 days to target any newly hatched nits.
Overall, chervil‑based aqueous preparations demonstrate a reliable pediculicidal effect, combining neurotoxic and desiccating actions while maintaining a favorable safety profile for human use.