Cognitive effects of chronic exposure to lead and solvents

Background. Occupational exposure to lead and solvents has declined steadily over the past 20 years, however construction workers continue to be exposed to these neurotoxicants. The purpose of this study was to investigate the cognitive effects of chronic occupational exposure to lead and solvents. Method. Based on K-XRF of tibial bone lead and occupational history of solvent exposure, subjects were classified into four exposure groups: lead (N = 40), solvent (N = 39), lead/ solvent (N = 45), and control (N = 33). All subjects completed tests to assess concentration, motor skills, memory, and mood. Results. Relative to controls, the lead, solvent, and lead/solvent groups performed significantly more poorly on a test of verbal memory, while the lead and lead/solvent groups were slower than the solvent and control groups on a task of processing speed. Bone lead was a significant predictor of information processing speed and latency of response while solvent exposure was a significant predictor of verbal learning and memory. Conclusions. Bone lead was associated with slower speed of processing while exposure to lead and/or solvents reduced efficiency of verbal learning. (C) 2003 Wiley-Liss, Inc.