TOXICOLOGICAL PROFILE FOR CHROMIUM - Davidborowski.com

CHROMIUM 512. HEALTH EFFECTSincrease in mitogen-stimulated T-cell response in the group exposed for 90 days to 0.2 mgchromium(VI)/m 3 . Bronchial alveolar lavage fluid had an increased percentage of lymphocytes in thegroups exposed to 0.025 and 0.05 mg chromium(VI)/m 3 and an increased percentage of granulocytes inthe groups exposed to 0.05 mg chromium(VI)/m 3 for 28 days. The phagocytic activity of macrophageswas increased in the 0.05 mg chromium(VI)/m 3 group. A higher number of macrophages in telophasewas observed in the 0.025 and 0.05 mg chromium(VI)/m 3 groups. Bronchial alveolar lavage fluid fromrats exposed for 90 days had an increased percentage of lymphocytes in the 0.025, 0.05, and 0.2 mgchromium(VI)/m 3 groups and an increased percentage of granulocytes and number of macrophages in the0.05 mg chromium(VI)/m 3 groups. The phagocytic activity of the macrophages was increased in the0.025 mg and 0.05 mg chromium(VI)/m 3 groups and decreased in the 0.2 mg chromium(VI)/m 3 group. Agreater number of macrophages in telophase and an increase in their diameter were observed in the 0.025,0.05, and 0.2 mg chromium(VI)/m 3 groups (Glaser et al. 1985).Low-level exposure to sodium dichromate seems to stimulate the humoral immune system (as evidencedby the significant increase in total immunoglobin levels); exposure to 0.2 mg chromium(VI)/m 3 ceases tostimulate the humoral immune system (significant decreases in total immunoglobin levels) but still mayhave effects on the T lymphocytes. The depression in macrophage cell count and phagocytic activitiescorrelated with a 4-fold lower rate of lung clearance for inhaled iron oxide in the 0.2 mgchromium(VI)/m 3 group (Glaser et al. 1985). The LOAELs for immunological effects in rats are recordedin Table 2-1 and plotted in Figure 2-1.2.2.1.4 Neurological EffectsIn a chrome plating plant where poor exhaust resulted in excessively high concentrations of chromiumtrioxide fumes, workers experienced symptoms of dizziness, headache, and weakness when they wereworking over the chromate tanks (Lieberman 1941). Such poor working conditions are unlikely to stilloccur in the United States because improvements in industrial hygiene have been made over the years.No increases in vascular lesions in the central nervous system were evident in a cohort of 3,408 workersfrom 4 former facilities that produced chromium compounds from chromite ore in northern New Jersey(Rosenman and Stanbury 1996). The proportionate mortality ratios for white and black men were 78(61–98) and 68 (44–101), respectively. The subjects were known to have worked in the four facilitiessometime between 1937 and 1971 when the last facility closed. Exposure durations ranged from 20 years.