Female mice drank water containing 180 ppm hexavalent chromium for 28 days, alongside groups fed the fungicides captan and folpet. All treated mice showed villous enterocyte hypertrophy and mild crypt hyperplasia in the duodenum, and after a 28-day recovery period the duodenum was generally indistinguishable from that of unexposed mice. The work was funded by an industry chemistry council panel on hexavalent chromium.
Key numbers
- Dose: 514 mg/L sodium dichromate dihydrate in tap water, about 180 ppm hexavalent chromium, verified weekly by method SW-846 7196A; detection limit 0.04 ppm hexavalent chromium (Materials and Methods, p. 1092).
- Group size 20 per group (10 dosing phase, 10 recovery phase) (Table 1, p. 1092).
Methods (brief)
GLP 28-day study with a 28-day recovery phase; standardized duodenal sampling (proximal, middle, distal), histopathology severity scoring and Ki-67 immunostaining.
Evidence fitness
Supports statements about the duodenal histopathology of high-dose hexavalent chromium in mice and its reversibility after exposure ends. It does not establish effects at drinking-water concentrations relevant to people.
Limitations
Single high dose, female mice only, short exposure. Funded by the hexavalent chromium panel of the American Chemistry Council; most authors work at consulting firms.
Related evidence
Update history
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