Mosquito coil
Encyclopedia
Mosquito coil is mosquito
-repelling incense
, usually shaped into a spiral, and typically made from a dried paste of pyrethrum
powder. The coil is usually held at the center of the spiral, suspending it in the air, or wedged by two pieces of fireproof nettings to allow continuous smoldering. Burning usually begins at the outer end of the spiral and progresses slowly toward the centre of the spiral, producing a mosquito-repellent smoke. A typical mosquito coil can measure around 15 cm in diameter and lasts up to 8 hours. Mosquito coils are widely used in Asia, Africa, and South America.
was used for centuries as an insecticide
in Persia and Europe, and the mosquito coil was developed around 1890s by a Japanese
business man, Eiichiro Ueyama.
At that time in Japan, people usually mixed pyrethrum powder with sawdust and burned it in a brazier or incense burner to repel mosquitoes. Initially, Ueyama created incense sticks mixed from starch powder, dried mandarin orange skin powder, and pyrethrum powder. However, the bar-shaped mosquito sticks quickly burned up in about 40 minutes, too brief for a long repelling action. In 1895, his wife, Yuki, proposed making the sticks thicker and longer, and curling them in spirals. In 1902, after a series of trials and errors, he finally obtained a desired incense burning effect out of a spirally-shaped mosquito repellent. The method involved cutting from a thick bar of incense to a certain length and manually winding it. This method continued to be used until 1957, where mass production was made possible through machine punching, making a far larger manufacturing scale possible.
After the Second World War, his company, Dainihon Jochugiku Co. Ltd, set up joint-venture firms in various countries, such as China
and Thailand
, to produce products suited to the actual local conditions.
from one burning coil can be as high as that released from 51 burning cigarettes.
Mosquito
Mosquitoes are members of a family of nematocerid flies: the Culicidae . The word Mosquito is from the Spanish and Portuguese for little fly...
-repelling incense
Incense
Incense is composed of aromatic biotic materials, which release fragrant smoke when burned. The term "incense" refers to the substance itself, rather than to the odor that it produces. It is used in religious ceremonies, ritual purification, aromatherapy, meditation, for creating a mood, and for...
, usually shaped into a spiral, and typically made from a dried paste of pyrethrum
Pyrethrum
Pyrethrum refers to several Old World plants of the genus Chrysanthemum which are cultivated as ornamentals for their showy flower heads. Pyrethrum is also the name of a natural insecticide made from the dried flower heads of C. cinerariifolium and C...
powder. The coil is usually held at the center of the spiral, suspending it in the air, or wedged by two pieces of fireproof nettings to allow continuous smoldering. Burning usually begins at the outer end of the spiral and progresses slowly toward the centre of the spiral, producing a mosquito-repellent smoke. A typical mosquito coil can measure around 15 cm in diameter and lasts up to 8 hours. Mosquito coils are widely used in Asia, Africa, and South America.
Invention
PyrethrumPyrethrum
Pyrethrum refers to several Old World plants of the genus Chrysanthemum which are cultivated as ornamentals for their showy flower heads. Pyrethrum is also the name of a natural insecticide made from the dried flower heads of C. cinerariifolium and C...
was used for centuries as an insecticide
Insecticide
An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
in Persia and Europe, and the mosquito coil was developed around 1890s by a Japanese
Japanese people
The are an ethnic group originating in the Japanese archipelago and are the predominant ethnic group of Japan. Worldwide, approximately 130 million people are of Japanese descent; of these, approximately 127 million are residents of Japan. People of Japanese ancestry who live in other countries...
business man, Eiichiro Ueyama.
At that time in Japan, people usually mixed pyrethrum powder with sawdust and burned it in a brazier or incense burner to repel mosquitoes. Initially, Ueyama created incense sticks mixed from starch powder, dried mandarin orange skin powder, and pyrethrum powder. However, the bar-shaped mosquito sticks quickly burned up in about 40 minutes, too brief for a long repelling action. In 1895, his wife, Yuki, proposed making the sticks thicker and longer, and curling them in spirals. In 1902, after a series of trials and errors, he finally obtained a desired incense burning effect out of a spirally-shaped mosquito repellent. The method involved cutting from a thick bar of incense to a certain length and manually winding it. This method continued to be used until 1957, where mass production was made possible through machine punching, making a far larger manufacturing scale possible.
After the Second World War, his company, Dainihon Jochugiku Co. Ltd, set up joint-venture firms in various countries, such as China
China
Chinese civilization may refer to:* China for more general discussion of the country.* Chinese culture* Greater China, the transnational community of ethnic Chinese.* History of China* Sinosphere, the area historically affected by Chinese culture...
and Thailand
Thailand
Thailand , officially the Kingdom of Thailand , formerly known as Siam , is a country located at the centre of the Indochina peninsula and Southeast Asia. It is bordered to the north by Burma and Laos, to the east by Laos and Cambodia, to the south by the Gulf of Thailand and Malaysia, and to the...
, to produce products suited to the actual local conditions.
Ingredients
The active ingredients found in mosquito coils can be some of the following:- PyrethrumPyrethrumPyrethrum refers to several Old World plants of the genus Chrysanthemum which are cultivated as ornamentals for their showy flower heads. Pyrethrum is also the name of a natural insecticide made from the dried flower heads of C. cinerariifolium and C...
(Natural, powdered material from a kind of chrysanthemum plant; performance moderated) - Pyrethrins (Extract of insecticidal chemicals in pyrethrum)
- AllethrinAllethrinThe allethrins are a pair of related synthetic compounds used in insecticides. They are synthetic pyrethroids, a synthetic form of a chemical found naturally in the chrysanthemum flower. They were first synthesized in the United States by Milton S. Schechter in 1949...
(sometimes d-trans-allethrin) (The first synthetic pyrethroid) - Esbiothrin (A form of allethrin)
- Dibutyl hydroxyl toluene (BHT) (An optional additive to prevent pyrethroid from oxidizing during burning)
- Piperonyl butoxidePiperonyl butoxidePiperonyl butoxide is an organic compound used as pesticide synergist, especially for pyrethroids and rotenone. It does not by itself have pesticidal properties. However, when added to insecticide mixtures, typically pyrethrin, pyrethroid, and carbamate insecticides, their potency is increased...
(PBO) (An optional additive to improve the effectiveness of pyrethroid) - N-(2-ethylhexyl)-bicyclo-(2,2,1)hept-5-ene-2,3-dicarboximide (MGK 264) (An optional additive to improve effectiveness of a pyrethroid)
Advantages
Mosquito coils nowadays burn without flame for up to eight hours of continuous repelling action. In quantitative tests, they provide about 80% protection. Mosquito coils are also cheap and need no special equipment to use it other than just lighting it up. They are portable and fit into normal household practices of lighting candles or incense.Disadvantages
There are several hazards that are known to be caused by mosquito coils. In 1999, sparks from mosquito coils ignited a fire that swept through a three-story dormitory building at a summer camp in South Korea; 23 persons, including 19 children, died in the blaze. Recent studies showed that the smoke generated from burning mosquito coil is of certain health concerns – one burning mosquito coil produces the same amount of particulate mass (diameter up to 2.5 μm) as 75-137 burning cigarettes would; and the emission of formaldehydeFormaldehyde
Formaldehyde is an organic compound with the formula CH2O. It is the simplest aldehyde, hence its systematic name methanal.Formaldehyde is a colorless gas with a characteristic pungent odor. It is an important precursor to many other chemical compounds, especially for polymers...
from one burning coil can be as high as that released from 51 burning cigarettes.