Neurobehavioral impairment and seizures from formaldehyde.

Three patients were evaluated for effects of formaldehyde on central nervous system function. Three patients had used formalin, formaldehyde with or without phenol, to fix whole animals for 14-30 y, and a fourth patient was covered several times by formaldehyde and phenol rainout from manufacturing spills. All were disabled, and two had developed seizures. They had elevated mood state scores (82 to 162) and elevated symptom frequency scores (111 to 138), compared with referent subjects. There was excessive fatigue, somnolence, headache, difficulty remembering, irritability, and instability of mood. Compared with referents, choice reaction time was prolonged in four of four (4/4) subjects, blink latency was delayed in 2/2, balance was abnormal in 3/4, and visual fields were constricted in 2/3. Cognitive functions, measured by Culture Fair, block design, and digit symbol tests, were impaired in all. Delayed verbal recall and visual reproduction were impaired in 3/4. Perceptual motor speed on slotted pegboard and trail making A and B tests was reduced in 4/4. Errors on fingertip number writing were abnormal in all. Long-term memory was decreased in only one. Extensive use of formaldehyde at work or repeated airborne exposure to formaldehyde and phenol appears to have impaired central nervous system function.