TOXICOLOGICAL PROFILE FOR CHROMIUM - Davidborowski.com

CHROMIUM 1922. HEALTH EFFECTSIn another experiment, treatment of dams on gestation days 7, 8, and 9 resulted in fetal malformations,whereas no developmental effects were noted in the fetuses of dams treated on days 10 or 11. Themalformations consisted of cleft palate from treatment on day 9, and small or absent kidneys aftertreatment on days 7 or 8 (Gale and Bunch 1979). Furthermore, the intravenous administration of0.005 mg chromium(VI)/kg as sodium dichromate to pregnant mice from days 8–18 of gestation resultedin the accumulation of .19% of the dose in the calcified areas of fetal skeleton and yolk sac (Danielssonet al. 1982).In contrast to chromium(VI), conflicting results have been found for chromium(III). No developmentaleffects were observed in the offspring of rats fed 1,806 mg chromium(III)/kg/day as chromium oxide for60 days before mating and throughout the gestational period (Ivankovic and Preussmann 1975).Alterations in the development of the reproductive system (decreases in relative weights of reproductivetissues and decreased number of pregnancies among female offspring) were observed in the male andfemale offspring of mice exposed to 74 mg chromium(III)/kg/day as chromium(III) chloride in thedrinking water on gestation day 12 through lactation day 20 (Al-Hamood et al. 1998). Intravenousadministration of 0.005 mg chromium(III)/kg as chromium trichloride to pregnant mice from days 8 to 18of gestation resulted in the accumulation of only .0.8% of the dose in the calcified areas of fetal skeletonand yolk sac (Danielsson et al. 1982). However, intraperitoneal injection of mice with $14 mgchromium(III)/kg as chromium trichloride during gestation resulted in cleft palate, exencephaly, neuraltube defects, and bone fusions (Iijima et al. 1983; Matsumoto et al. 1976).The results of animal studies therefore indicate that chromium(VI) compounds are development toxicants.Chromium(III) oxide was not a developmental toxicant in mice by the oral route but chromium(III)chloride was a developmental toxicant.Genotoxic Effects. In vivo studies of chromium compounds are summarized in Table 2-5. In vitrostudies on the genotoxicity of chromium(VI) and chromium(III) compounds are summarized inTables 2-6 and 2-7, respectively. Chromium(VI) compounds are capable of penetrating cell membraneswhile chromium(III) compounds, in general, are not; therefore, chromium(VI) compounds are of greaterconcern with regard to health effects. Studies involving workers exposed to chromium(VI) in stainlesssteel welding and electroplating (Husgafvel-Pursianen et al. 1982; Littorin et al. 1983; Nagaya 1986;Nagaya et al. 1991), and to chromium(III) in tanneries (Hamamy et al. 1987) did not report increases inthe number of chromosomal aberrations or sister chromatid exchanges in peripheral lymphocytes of theseworkers. No elevations in DNA strand breaks or hydroxylation of deoxyguanosine were detected in