A cluster of neurological signs and symptoms in soil fumigators.

Methyl bromide is a highly toxic and penetrating compound used extensively as a soil fumigant, in greenhouses and fields for the control of nematodes, fungi, and weeds. Here we report a cluster of neurological signs and symptoms in six methyl bromide fumigators employed in the same company. These workers showed a high prevalence of symptoms consistent with methyl bromide toxicity: fatigue and light-headedness, erectile dysfunction, headache, insomnia, paresthesia, hearing impairment and ringing in the ears, mood changes and loss of memory and concentration. Myoclonus and unsteady gait were present in three patients, epilepsy in one. Neurobehavioral assessment revealed memory impairment, deficit of attention and learning, and reduced ability to reproduce a complex drawing. The overall clinical picture of the six workers suggests that chronic low-level occupational exposure to methyl bromide, or repeated sub-acute accidental exposures, can cause adverse health effects. Strict hygienic surveillance of fumigation workers is highly recommended.