Amitraz is a chemical compound primarily utilized as an insecticide and acaricide, controlling insects, ticks, and mites. First synthesized in England in 1969, this non-systemic compound works through contact and repellent effects. It is widely applied due to its effectiveness against various pests.
Common Uses of Amitraz
Amitraz serves multiple purposes across veterinary medicine, agriculture, and beekeeping. In veterinary applications, it is widely used as an ectoparasiticide for dogs, cattle, goats, sheep, and pigs. For dogs, amitraz is found in tick collars and topical solutions to manage infestations of ticks, fleas, and mites, including demodicosis. It is applied externally as dips or washes for livestock, targeting mites, lice, and ticks. Cats are particularly sensitive to amitraz, and its use in them requires veterinary guidance.
In agriculture, amitraz is a pesticide for controlling mites and insects on various crops. It is commonly applied to pears for pear psylla, and manages whiteflies and mites on cotton. Its use extends to various fruits, vegetables, and ornamental plants. Application methods include foliar sprays, airblast, or ground boom spraying.
In apiculture, amitraz protects honey bee colonies from the Varroa mite. Beekeepers use strips or in-hive formulations to control these mites. This helps maintain bee population health.
How Amitraz Works
The effectiveness of amitraz stems from its action as an alpha-2 adrenergic agonist, affecting the nervous system of target pests. It disrupts normal nerve function by interacting with octapamine receptors within their central nervous system, leading to overexcitation.
This overstimulation is accompanied by the inhibition of monoamine oxidases and prostaglandin synthesis. The combined effect results in paralysis, followed by the death of insects and mites. This mechanism explains why amitraz is so potent against these specific ectoparasites while generally being less harmful to mammals, though adverse effects can occur with misuse or overdose.
Signs of Amitraz Toxicity
Exposure to excessive amounts of amitraz can lead to toxic effects in both animals and humans. In pets, especially dogs and cats, common signs of poisoning appear within 2 to 6 hours after exposure. These include sedation, weakness, and an uncoordinated gait. Other observable symptoms may involve a slow heart rate, low body temperature, vomiting, and dilated pupils.
Affected animals might also experience high blood sugar and decreased intestinal motility. Cats are particularly sensitive to amitraz, and even small exposures can be serious, with signs persisting for 24 to 72 hours.
In humans, symptoms of amitraz exposure can arise from accidental ingestion or significant skin contact, often presenting similarly to those seen in pets. Individuals may experience drowsiness, dizziness, and low blood pressure. Other signs include a slow heart rate, hypothermia, constricted pupils, and elevated blood sugar levels. In more severe cases, loss of consciousness, vomiting, and respiratory failure have been reported. Anyone suspecting amitraz poisoning in a human should seek immediate medical attention.
Safety and Regulation
Safe handling of products containing amitraz is important to minimize exposure risks. When applying these products, it is advisable to wear personal protective equipment, such as gloves, goggles, and masks, to prevent skin contact and inhalation of vapors. After application, hands should be thoroughly washed to remove any residues.
Particular care should be taken with children, ensuring they do not come into contact with treated pets, especially tick collars, for a period specified on the product label. Proper disposal of unused solutions and product containers, often by flushing diluted solutions down a drain or wrapping collars in newspaper before discarding, helps prevent environmental contamination and accidental exposure.
Amitraz is subject to regulation by government agencies, such as the Environmental Protection Agency (EPA) in the United States. These agencies approve specific formulations for particular uses and establish tolerances for residues in various commodities. The EPA has classified amitraz as a Group C (possible human) carcinogen, based on studies showing tumor formation in mice, reinforcing the need for regulated use. Its classification as a restricted-use pesticide in many regions highlights the importance of adhering strictly to label directions to ensure both effectiveness and safety.