The carbamate family of insecticides, often highly toxic to
humans, is widely used in homes, garden and agriculture. Pesticides in the
carbamate family include aldicarb (Temik), bendiocarb, carbaryl (Sevin),
carbofuron, fenoxycarb, methomyl, pirimicarb and propoxur. In 1996, 1030
cases of carbamate pesticide poisonings, including 202 cases involving
children, were reported to the American Association of Poison Control
Centers, although far more poisonings occur each year than are actually
reported (Reigart et al., 1999). Like organophosphate insecticides,
carbamates are also
cholinesterase inhibitors and in cases of double exposure, the effects
would be additive. Carbamates cause the reversible carbamylation of the
acetylcholinesterase enzyme, allowing accumulation of acetylcholine in the
central nervous system (Reigart et al., 1999). While the symptoms of
carbamate and organophosphate poisoning are identical and may be equally
severe, carbamate poisoning generally runs a shorter course (Solomon,
The accumulation of acetylcholinesterase in the brain due to carbamate poisoning may cause sensory and behavioral disturbances, incoordination, headache, dizziness, restlessness, anxiety, depressed motor function and seizures (Reigart et al., 1999). Severe intoxication may result in psychosis, seizures, and coma. Other symptoms of carbamate poisoning include wheezing, nausea, vomiting, diarrhea, ocular meiosis, muscle weakness, and salivation. Carbamate poisonings are often misdiagnosed as gastroenteritis, influenza, bronchitis, or a wide range of other illnesses (Solomon, 2000). Even severe poisonings requiring intensive care unit admission was misdiagnosed 80% of the time in one series, with diagnoses including pneumonia, meningitis, and epilepsy. Studies have shown some carbamates to be carcinogenic (EPA, 1997).
Reigart, J., M.D. et al.,
Recognition and Management of Pesticide Poisonings, EPA, 1999.
Gina, M.D., Pesticides and Human Health: A
Resource for Health Care Professionals, Physicians for Social
Responsibility and Californians for Pesticide Reform, 2000.
U.S. EPA. 1997. Office of Pesticide Programs list of chemicals evaluated for carcinogenic potential. Memo from W.L. Burnman, HED, to HED branch chiefs. Washington, DC. February 19.