Mosquito coil

The coil is usually held at the center of the spiral, suspending it in the air, or wedged by two pieces of fireproof netting to allow continuous smoldering.

[2] Pyrethrum was used for centuries as an insecticide in Persia and Europe,[3] being developed into a mosquito coil in the late 1800s by a Japanese couple: Yuki and Eiichiro Ueyama [ja].

[4][5] After the Second World War, his company, Dainihon Jochugiku Co. Ltd, established joint-venture firms in various countries, including China and Thailand, to produce mosquito-repelling products based on local conditions.

In 1999, a fire in a South Korean three-story dormitory caused the death of 23 people when a mosquito coil was left unattended.

They showed signs of sensory irritation from the high smoke concentration, but there were no adverse effects on other parts of the body.