The Principle And Ingredients Of Mosquito Coils

Principle

Solid electric mosquito repellents work by absorbing insecticide (pyrethrum) into a paper disc, which is then evaporated by heat. The effect typically lasts 6-8 hours. A drawback is that while the initial effect is strong, potentially exceeding the recommended dosage, the insecticide evaporates after 4-5 hours, reducing effectiveness and mosquito repellency.

Liquid electric mosquito repellents utilize capillary action, continuously heating and releasing insecticides, overcoming the shortcomings of solid repellents. Liquid repellents can be used continuously for extended periods, approximately 60 days, and can even be timed for release.

Mosquito coils, on the other hand, use high-temperature combustion to slowly release insecticides into the air, offering a greater mosquito-repelling effect than a killing effect.

Ingredients

Mosquito coils contain organophosphates (trichlorfon/chlorpyrifos/chlorpyrifos), carbamates (propoxur/methoxyfenozide), and pyrethroids (cypermethrin/cypermethrin/propargyl/allethrin/ES bio-pyrethroids). Organophosphates are the most toxic, while pyrethroids are the least toxic, classified as slightly toxic.

The carrier of mosquito coils is carbon powder, sawdust, etc., while the carrier of electric mosquito repellents is hydrocarbons.

Mosquito coils produce more pollution and smoke, making them suitable for outdoor use, such as on balconies. Tablet-type and liquid electric mosquito repellents produce less pollution and are suitable for indoor use.