Chlorothalonil

Abstract

Chlorothalonil is a broad-spectrum organochloride pesticide. It is primarily used as a fungicide, bactericide, and nematicide, and has been reported to be effective on a wide range of vegetables and fruit crops. It is also used as a bactericide, nematicide, and mildew-preventing agent in paints. The primary routes of exposure to chlorothalonil are ingestion, inhalation, dermal, and ocular. Occupational exposure to chlorothalonil may occur through inhalation of dusts or dermal contact with this compound at workplaces where it is produced or used as a pesticide. The greatest potential for dermal and inhalation exposure to chlorothalonil is expected for pesticide applicators and farm workers who have frequent contact with products containing this compound. Monitoring data indicate that the general population may be exposed to chlorothalonil via inhalation of ambient air and ingestion of food. Chlorothalonil gets rapidly absorbed when ingested and inhaled. Liver is the primary site of metabolism of chlorothalonil via conjugation with glutathione. It is a hepato-, nephro-, neuro-, and reproductive toxin with carcinogenic potential. It is a well-known skin and eye irritant that is reported to cause severe hypersensitivity reaction even in the absence of direct skin contact, owing to its high volatility. Typical hypersensitivity reactions following chlorothalonil exposure include erythema, edema, eczema, and pruritus. Chlorothalonil is moderately persistent in soil, and its primary breakdown product in soil is 4-hydroxy-2,5,6-trichloroisophthalonitrile. Chlorothalonil is considered Group B2, probable human carcinogen. In case of overexposure, gastrointestinal decontamination and administration of activated charcoal along with cathartic sorbitol should be considered.