Arsenic exposure to smelter workers. Clinical and neurophysiological studies.
Forty-seven copper smelter workers, exposed to airborne arsenic for 8-40 years, were examined clinically with electromyography, and the motor and sensory conduction velocities in their arms and legs were determined. Fifty age-matched industrial workers not exposed to arsenic formed a reference group. The level of arsenic in the air at the smeltery was estimated to be below 500 micrograms/m3 before 1975 and approximately 50 micrograms/m3 thereafter. Urine analyses of arsenic showed a mean value of 71 micrograms/l (1 mumol/l) in the exposed group; this value is lower than that found in earlier studies reporting clinically detectable neuropathy. Only minor neurological and electromyographic abnormalities were found. A slightly reduced nerve conduction velocity in two or more peripheral nerves was more common among the arsenic workers than the referents, and a statistically significant correlation between cumulative exposure to arsenic and reduced nerve conduction velocity in three peripheral motor nerves was found. This occurrence was interpreted as a sign of slight subclinical neuropathy. In conclusion the risk of clinically significant neuropathy is small when exposure is kept below 50 micrograms/m3 in workroom air. The subclinical findings may be of interest in relation to the prevention of early adverse health effects from arsenic exposure.
D000328:Adult; D000368:Aged; D000395:Air Pollutants, Occupational / Q000009:adverse effects*; D001151:Arsenic / Q000009:adverse effects*; D004576:Electromyography; D006801:Humans; D008297:Male; D008669:Metallurgy; D008875:Middle Aged; D009431:Neural Conduction / Q000187:drug effects; D009784:Occupational Diseases / Q000139:chemically induced*; D010523:Peripheral Nervous System Diseases / Q000139:chemically induced*; D013548:Sweden; D013997:Time Factors
D000395:Air Pollutants, Occupational; D001151:Arsenic