Dicofol is an insecticide used to control mites on a variety of vegetable, fruit, ornamentals and field crops. Structurally, it's similar to DDT, the banned pesticide made famous by Rachel Carson's 1962 book Silent Spring.
According to the World Health Organization, humans can potentially be exposed through “pears, blackcurrants and strawberries.” It is not very mobile in the environment and is expected to be found rarely in water, except in the case of large spills or similar disasters.
Dicofol is moderately toxic with acute exposure, with central nervous system symptoms including nausea, dizziness, weakness, and vomiting. Long term exposure can lead to affects on the liver, kidneys, heart, and adrenal glands. It is not believed to be carcinogenic.
The EPA recommends hydrolysis for the treatment of dicofol. According to the WHO, there is also the possibility that it may also be treatable with activated carbon:
No information is available on removal of dicofol during water treatment. However, the relatively low aqueous solubility and high octanol–water partition coefficient suggest that dicofol should be removed by adsorption onto activated carbon and may possibly be removed during coagulation
Sources: EPA (1), EPA (2), WHO, EXTOXNET, Photo: WikiMedia, author: 3268zauber
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