Additional information about study design, protocols, and test article preparation and validation is available in

NTP (2008) Specifications for the conduct of studies to evaluate the toxic and carcinogenic potential of chemical, biological and physical agents in laboratory animals for the National Toxicology Program (NTP)

https://hero.epa.gov/hero/index.cfm/reference/details/reference_id/4135252

B6C3F1 Mouse (50/sex/group)

Water:

0, 14.3, 28.6, 85.7, 257.4 ppm sodium dichromate dihydrate (M)

0, 14.3, 57.3, 172, 516 ppm sodium dichromate dihydrate (F);

equivalent to

0.450 0.914 2.40 5.70 mg Cr VI/kg-d (M)

0.302 1.18 3.24 8.89 mg Cr VI/kg-d (F)

F344 Rat (50/sex/group)

Water:

0, 14.3, 57.3, 172, 516 ppm sodium dichromate dihydrate;

equivalent to

0.200 0.796 2.10 6.07 mg Cr VI/kg-d (M)

0.248 0.961 2.60 7.13 mg Cr VI/kg-d (F)

7 d/wk, 104 wk

Time-weighted average daily doses are available in the study and endpoint list (denoted ADD).

Note: time weighted average daily doses, or mg/kg-d (ADD) represent the time weighted average over the course of 2 years using weekly consumption data from the NTP report. As a result, the nominal mg/kg-d, or the mg/kg-d (ADD) may not be accurate for animals with different observation times (ie, 4, days, 22 days, 3 months, 6 months, or 12 months). At earlier time points, rodents ingested a higher dose due to greater water consumption during the growth period.

F344 rats (combined male and female data)