Mosquito coils, a summer tradition in Japan

 An indispensable item for summer in Japan: mosquito coils

Mosquito coils are an indispensable part of the Japanese summer, with smoke trailing from green whirlpools over the veranda and eaves where a refreshing night breeze blows, and people in yukata (summer kimono) love fireworks with a fan in hand.

The rainy season has ended nationwide, and the "Japanese summer" has arrived with full-blown heat. During this season, mosquito repellents are indispensable in preparation for the arrival of mosquitoes, whose wings make unpleasant noises and are known to cause various illnesses. Various styles of mosquito repellents, such as electronic mosquito repellents, are available in the market, but the most popular is the green swirl mosquito coil. It is a summer tradition.

History of Mosquito Coils

Mosquito coils are said to have their roots in "kayaribi," or mosquito coils used in the Heian period (794-1185). At that time, mosquitoes were repelled by burning mugwort leaves, kaya wood, and green leaves of cedar and pine trees in a brazier to cook the smoke and smother it. The practice has been described as "mosquito fire" or "mosquito fire" in classical Japanese essays, waka poems, and haiku.

Eventually, in the mid-Meiji period, Dainippon Pyrethrum Co., Ltd. developed the first mosquito coil with an insecticidal effect.

Pyrethrum, the raw material of mosquito coils, is a perennial herb of the Asteraceae family, and its Japanese name is "Shirobanamushiyokegiku". Its country of origin is the Republic of Serbia, and its flowers have long been said to have insecticidal properties.

Insect repellent chrysanthemums were first introduced to Japan in 1886.

Seeds were sent from the U.S. to the founder of Dainippon Pyrethrum, and "mosquito coils" were created by kneading insect repellent chrysanthemums into incense sticks. Later, pyrethrum was successfully cultivated in Japan, mainly in Wakayama Prefecture, and spread throughout Japan.

Why are mosquito coils green in color?

Mosquito coils were invented in 1890, inspired by Buddhist altar incense sticks, but each stick lasted only about 40 minutes. However, each stick lasted only about 40 minutes, had little insecticidal effect due to its thinness, and was prone to breaking during transportation.

After much research and development, Mrs. Eiichiro Ueyama, the founder of "Kintyo", saw a "coiled snake", which led to the development of the whirlpool shape. The green color is said to be cool and refreshing. Another reason is that the green color is cooler, and it was inspired by the color of the leaves of mugwort and other grasses that were burned during "mosquito repellent" before mosquito coils were invented.

What are the ingredients of mosquito coils?

Mosquito coils are made by mixing pyrethroid, the active ingredient, with wood flour and other plant ingredients, adding tab powder, starch, and other binding agents, kneading the mixture, and then spiraling it into a dry spiral. The heat generated when the incense sticks burns volatilizes the active ingredients, which spread with the smoke to eliminate mosquitoes.

The original insecticidal ingredient in mosquito coils was pyrethrin, a natural insecticide found in what is now the Republic of Serbia.

Pyrethrum cultivation in Japan began in Wakayama Prefecture, where 13,000 tons were produced in 1938. In addition, the development of pyrethroid, a synthetic pyrethrin-like compound similar to pyrethrin, a natural insecticide, led to the use of chemically synthesized pyrethroids as the active ingredients in mosquito coils and other household insecticides in Japan.

Many people are "soothed by the scent of mosquito coils," and in order to preserve the unique aroma, Kincyo still mixes pyrethrum powder (lees powder) with the raw materials after squeezing the active ingredient of pyrethrum.