Safety of pyrethroid-treated mosquito nets

The use of insecticide treated nets (ITNs) for personal protection against malaria vector Anopheles mosquitoes (Diptera: Culicidae) has become popular during the past decade. With the precautions outlined in this paper, field use of pyrethroids - at concentrations recommended for treatment of mosqui to nets - poses little or no hazard to people treating the nets or to users of the treated nets. With frequent exposure to low concentrations of pyret hroids, the risk of toxicity of any kind is remote. Pyrethroids entering th e systemic circulation are rapidly metabolized to much less toxic metabolit es. Toxicologically, pyrethroids have a useful characteristic - the product ion of skin paraesthesia - which gives an early indication of exposure. Thi s reversible symptom of exposure is due to transient stimulation of periphe ral sensory nerves and not a toxic effect. In the retail market, for home u se, the provision of proper packaging and labelling, with clear instruction s on safe and effective use of the product are most important. Because many domestic users of pyrethroid 'home treatment kits' for ITNs may not be ful ly literate, it is essential that 'instructions for use' should be portraye d via pictograms with supporting text in appropriate local language(s).