We explored the effect of pentabromodiphenyl ether (PBDE) exposure on Wistar Han rats pups on postnatal day 22. PBDE-47 is a congener of a PBDE mixture (DE-71) that was chosen as the test PBDE congener to compare PBDE-47 toxicity to the toxicity of DE-71. In utero and postnatal exposure was performed using chemical concentrations of 0, 0.1, 15, and 50 mg/kg by gavage. Both PBDE-47 and DE-71 exposure led to centrilobular hypertrophy and fatty change in liver and reduced serum thyroxin levels by PND 22. Liver transcriptomic changes included induced cytochrome p450 transcript levels and up-regulation of Nrf2 antioxidant pathway transcripts and up-regulation of ABC membrane transport transcripts. These transcriptional changes suggest that exposure to PBDE-47 and DE-71 could be a liver toxin or carcinogen after long-term exposure. A genomic benchmark dose concentration calculation showed that PBDE-47 exposure led to lower benchmark dose concentration than exposure to DE-71.