Psychiatric Signs and Symptoms Attributed to Insecticides

Several psychiatric manifestations result from CH and OP insecticide poisonings (Table 4-3). Assessment of the psychiatric effects of 

The CH insecticide chlordecone caused a serious neurotoxic epidemic in the United States. Because of poor industrial control at the world s only chlordecone plant in Hopewell, Virginia, a mass industrial poisoning and environmental disaster occurred in the 1970s. An internist and neurologist, working independently, diagnosed the first victims (Cannon et al. 1978 Taylor et al. 1980). Psychiatric symptoms developed in 44% of the 133 workers and 19% of the 158 residents (Cannon et al. 1978). These complaints persisted for several weeks after exposure was terminated and included confusion and auditory and visual hallucinations (Taylor et al. 1978). 

An early case report of aldrin poisoning (Spiotta 1951) identified a confounding factor in chemical exposures. Persons may use insecticides in suicide attempts, and a survivor of suicidal poisoning may have a preexisting psychiatric condition. The insecticide may organically modify his or her condition. Most insecticides contain solvents that promote the potential of a combined effect of insecticide and solvent ingestion. Certain symptoms may result from solvent rather than insecticide exposure. 

Organophosphate pesticides do not cause a significant percentage of major mental illnesses, such as schizophrenia and bipolar disorder, but they do cause severe psychiatric symptoms of both acute and chronic duration. The most prominent psychiatric symptoms include early anxiety and emotional lability, followed by insomnia, excessive dreaming, nightmares, and reduced concentration. Other symptoms listed in Table 4-3 usually develop only after exposures severe enough to cause physical symptoms but may occur at lower doses in individuals with genetic vulnerability. The limited informa- 

Mood Irritability, nervousness, depression, anxiety, mood lability 

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