Environmental Medicine: Integrating a Missing Element into Medical Education

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Table 1. Human Reports of Trimethyltin Intoxication

Source, y	Clinical Features	Tests	Comments
Foxtemps et al,⁴ 1978; case reports (two chemists)	Headaches, memory defects, pain, loss of vigilance, insomnia, anorexia, confusion, disorientation, seizures (clonic tonic)	Electroencephalogram normal, theta waves (after secobarbital)	No urinary, blood, or air monitor or neuropsychiatric test; confounded by dimethyltin or monochioromethane exposure for 3 mo
Brown et al,⁵ 1979; case report (chemist)	Hyperactivity, insomnia, alternate hyperactivity; and absentmindedness	None reported	Not a full case report; duration of exposure not stated; full recovery
Ross et al,⁶ 1981 and 1983²⁰; epidemiologic study: compared 12 workers with high exposure with 10 with low exposure	Alternatting attacks of rage and deep depression, forgetfulness, headaches, loss of Ilbido and motivation, sleep disturbance, disortentation, burns, fatigue, weakness, poor concentration, dim vision, stuttering attacks	Urine tin levels 20 to 200 parts per billion (ppb); electroencaphalogram, no specific abnormalitites; slow nerve conduction velocity; impaired verbal memory, fine hand-eye coordination, visual motor integration, finger tap speed and learning; emotional disturbances	Details of neuropsychiatric tests not stated; longest follow-up 2 y and 10 mo; confounded by dimethythand methylchloride; variable outcome on follow-up from personality changes to complete recovery
Rey et al,⁷ 1984; and Besser et al,⁹ 1987; case reports (6 workers)	Hearing loss, amnesia, disorientation, confabulation, confusion, restlessness, aggressiveness, hyperphagia, seizures, nystagmus, ataxia, neuropathy, blurred vision, disturbed sexual behavior, death	Urine tin 445 to 1580 ppb (4–8 d after exposure); electroencaphalogram mostly normal; theta activity in fatal case; chest roentgenogram indicated respiratory distress syndrome in most severe cases; autopsy showed necrosis in limbic system and pontine and cerebellar structures	Confounded by dimethyttin and methylchloride; urine fevels less than 20 ppb 2 mo after exposure; neuropsychiatric testing not reported
Present case; a chemist; accidental severe single exposure	Disorientation, incongruous affect, memory defects, abnormal cognitive process, complex partial seizures, depression, fatigue, insomnia, amotivation, and indifference	Urine tin 52 ppb, 17 d after exposure; 10 ppb; 35 d after exposure (normal, <18); serum 13 ppb, 17 d after exposure; 7.4 ppb, 35 d after exposure (normal, < 3.3); electroencephalogram; left paroxysm; temporary theta; magnetic resonance imaging normal; detailed serial neuropsychological assessments over 4-y period	Acute exposure urine level >52 ppb; neuropsychological testing revealed residual memory impairments; memory and mood complaints; seizures persistent

could not find the bathroom or remember his visitors. He was disoriented to place and time. He mumbled repetitive statements to himself about the accident. Gait was normal. Tendon reflexes were 2+ equally. He was without pathologic reflexes, and the results of his sensory examination were normal. There was no papilledema. A computed axial tomographic scan was normal. An initial electroencephalogram showed 4- to 5-Hz paroxysmal theta waves over the left temporal area. Asymmetric 3- to 4-Hz delta waves developed on the left side with drowsiness or hyperventilation. Neuropsychological testing revealed significant impairment in new learning of verbal and visuospatial information on the Wechsler Memory Scale-Revised (WMS-R) and performance on the visual-motor and visuospatial subtests of the Wechsler Adult Intelligence Scale-Revised (WAIS-R) were only average. A performance IQ (PIQ) equal to 106 was well below the PIQ of 124 earned in a school assessment 2 years prior to the accident.

Repeated (partial) neuropsychological testing done 10 days after exposure showed some recovery of cognitive function. A PIQ was then identical to premorbid levels. Immediate recall of verbal and visuospatial information on the WMS-R improved, but his delayed recall continued to show forgetfulness (46% on the verbal task and 23% on the visuospatial task).

Urine and serum tin assays done on the 17th day after exposure showed 13 parts per billion (ppb) of trimethyltin (normal, <3.3 ppb). The trimethyltin concentration was still elevated (7.4 ppb) on the 35th day after exposure. The initial urinary trimethyltin level was 52 ppb (normal, <18 ppb), but this had fallen to 10 ppb by the 35th day after exposure (analyses by gas chromatographic mass spectrography, National Medical Services, Willow Grove, Pa).

His memory had not stabilized by the time he was discharged 18 days after exposure. He became lost in his hometown and his parents complained that he was “acting strange” and could not recall information presented to him.

A repeated electroencephalogram 3 months after exposure continued to show excessive scattered slow fre-

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Environmental Medicine: Integrating a Missing Element into Medical Education (1995)
Institute of Medicine (IOM)

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Related Titles

Environmental Medicine: Integrating a Missing Element into Medical Education (1995) Institute of Medicine (IOM)

Environmental Medicine: Integrating a Missing Element into Medical Education (1995)
Institute of Medicine (IOM)