Toxicity test designs body weights

A 52-week study in monkeys was designed to evaluate ocular effects. Despite the absence of adverse toxicological effects at the highest dose tested (20 mg/kg body weight per day), the study was considered inappropriate for the establishment of an ADI in view of the much higher doses used in several other studies and found to be without effects. The available comparative toxicokinetic data for humans and rats indicated that studies of toxicity in rats could be used to derive an ADI. 

Animal data are available for intermediate exposures by the inhalation and dermal routes of exposure. No animal data were located by the oral route. Most of these studies found no evidence of toxicity in any of the exposure conditions used in each (Carpenter et al. 1976 Bruner 1984 Lock et al. 1984 NTP/NIH 1986). However, the lack of toxicity in these studies has not been verified by more than one study using the same fuel oil, species, and/or route of exposure. In one aerosol inhalation study (Dalbey et al. 1987) there were positive findings for respiratory, hematological, and body weight effects at higher doses than those used in the studies by Carpenter et al. (vapor) (1979) and Lock et al. (aerosol) (1984). However, MRLs cannot be derived from these data because the Dalbey et al. study was not designed to test for a dose-response relationship, and therefore, the exact LOAEL(s) could not be determined for these effects. 

In obese rats fed diets containing 0.5, 2.4, 4.9, or 7.3% (77, 388, 778, or 1244 mg/kg body weight HCA) garcinia extract for 92 days, animals on the 4.9% or higher diets had testicular atrophy and toxicity (Saito et al. 2005). The design of this study has been questioned for accuracy as a test of testicular toxicity (Burdock et al. 2005). 

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