TOXICOLOGICAL PROFILE FOR CHROMIUM - Davidborowski.com

CHROMIUM 992. HEALTH EFFECTSSplenocytes prepared from rats given potassium chromate in their drinking water at 16 mgchromium(VI)/kg/day for 3 weeks showed an elevated proliferative response of T-and B-lymphocytes tothe mitogens, concanavalin A and liposaccharide, compared with splenocytes from control rats. A 5-foldenhancement of the proliferative response to mitomycin C was also seen when splenocytes from ratsexposed for 10 weeks were incubated with splenocytes from nonexposed rats and additional chromium(0.1 mg chromium(VI)/L) was added to the incubation compared to the system without added chromium.It was suggested that these increased proliferative responses represent chromium-induced sensitization(Snyder and Valle 1991). The LOAEL values are recorded in Table 2-2 and plotted in Figure 2-2.2.2.2.4 Neurological EffectsThe only information regarding neurological effects in humans after oral exposure to chromium(VI) is thereport of an enlarged brain and cerebral edema upon autopsy of a 14-year-old boy who died afteringesting 7.5 mg chromium(VI)/kg as potassium dichromate (Table 2-2 and Figure 2-2). These effectsmay be the result of accompanying renal failure (Kaufman et al. 1970).A decrease in motor activity and balance was reported in rats given 98 mg chromium(VI)/kg/day assodium chromate in drinking water for 28 days (Diaz-Mayans et al. 1986) (Table 2-2 and Figure 2-2).Histological examination of the brain and nervous system did not reveal abnormalities in rats fed2,040 mg chromium(III)/kg/day as chromium oxide in the diet 5 days/week for 2 years (Ivankovic andPreussmann 1975); however, more sensitive neurological, neurochemical, or neurobehavioral tests werenot conducted.2.2.2.5 Reproductive EffectsNo studies were located regarding reproductive effects in humans after oral exposure to chromium or itscompounds.A number of studies have reported reproductive effects in rats and mice orally exposed to chromium(VI).Sodium dichromate(VI) was administered by gastric intubation to groups of 10 mature male CharlesFoster strain rats at levels of 20, 40, and 60 mg chromium(VI)/kg/day for 90 days (Chowdhury and Mitra1995). Testis weight, population of Leydig cells, seminiferous tubular diameter, testicular protein, DNA,and RNA were all significantly reduced at 40 and 60 mg chromium(VI)/kg/day. The number ofspermatogonia was not affected by treatment; however, resting spermatocytes (high dose), pachytene