Saccadic eye movements among copper smelter workers.

Saccade accuracy was studied in 87 copper smelter workers. Findings were compared with those obtained in 52 lead-exposed automobile production workers and 52 controls examined as part of a separate study. Both groups of workers showed a decrease in saccade accuracy compared to controls. Saccade accuracy was reduced in copper smelter workers over 50 years of age compared to automobile production workers in this age group. Decreased saccade accuracy was not correlated with blood lead (Pb-B), zinc protoporphyrin (ZPP), or urinary arsenic (As-U) levels among copper smelter workers, but was significantly correlated with both Pb-B and ZPP in the group of automobile production workers. Saccade accuracy decreased significantly with age and duration of exposure only in the group of copper smelter workers. Complex exposures to lead and other toxic agents present in the smelter may account for the reduction in saccade accuracy among copper smelter workers.