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In a 90-day subchronic study, female F344 rats were exposed to doses of 0, 250, 1000, 2000, 3000, and 4000 ppm in feed.^11,20 The most sensitive apical endpoint was diffuse transitional epithelial hyperplasia of the bladder with BMD10 and BMD10_L values of 1567 and 971 ppm, respectively.¹¹ A ½ log range above and below the apical BMD of 1567 ppm is shown at the top of the plot. The ½ log range is shown to facilitate comparison with the genomic BMD values. Not shown on the plot is the transitional cell carcinoma of the bladder BMD and BMD_L values of 2002 and 1499 ppm, respectively, that were derived from 2-year study findings in the same rat strain.^11,21 In a 5-day GDRS, male F344 rats were exposed to doses of 0, 250, 1000, 2000, 3000, and 4000 ppm in feed, and bladder gene expression was measured. BMDExpress 2.0 was used to identify the most sensitive gene-set BMD, BMD_L, and BMD_U values from the GO Biological Processes² and the MSigDB C2 set.³ The BMD_L-to-BMD_U ranges of the most sensitive gene sets in both cases were less sensitive than the ½ log range of the most sensitive apical BMD from the 90-day subchronic study.