suggesting a mechanism by which shark cartilage might possibly lead to serious adverse events, such as teratogenicity. Establishing an appropriate level of concern from these data would have required additional information to place the antiangiogenic activity in perspective. Specifically, information about functionally related antiangiogenic substances would suggest that these agents could potentially cause serious effects, including teratogenic effects. This information indicates that the effect observed in animal data is a Category A effect (severe developmental effects, Table 5-1). Dose comparisons between animals and humans are difficult because of the wide variability in products referred to as shark cartilage, and the fact that the shark cartilage was not orally administered in the reports of antiangiogenic effects in animals. Because the constituent responsible for this purported activity is unknown, its concentration in blood cannot be compared between animals and humans.

In addition to the information presented above, use by a potentially vulnerable subpopulation raises concern. Shark cartilage appears to be used largely and to a significant degree by people with significant and often life-threatening diseases, such as cancer and rheumatoid arthritis, who, as a result of their disease or medical treatments, may be at increased risk for supplement-drug interactions and certain other adverse events, such as liver-related problems. Thus even without signals of higher concern to suggest an integrative evaluation in reaction to signals, a proactive integrative evaluation might be justified if resources are available to proactively conduct them.

Of the three items mentioned above (liver effects, antiangiogenic potential, and use by vulnerable subpopulations), the antiangiogenic potential raised sufficient concern to warrant a reactive integrative evaluation. The integrative evaluation could therefore be focused on the very limited amount of data addressing this potential concern. The limited amount of data resulted in significant data gaps in the prototype shark cartilage monograph. Conclusions of higher concern were not reached, but the limited amount of data adequately addressing the issue left questions about shark cartilage’s antiangiogenic potential in pregnant women. There is no information to suggest that women of child-bearing age are particularly likely to use the ingredient, which appears to be used largely in an effort to treat cancer and age-related conditions.

The shark cartilage prototype monograph also illustrates the wide difference in preparations of some dietary supplement ingredients. Powders could widely differ from extract preparations. Consistent with the guiding principles, safety concerns raised with shark cartilage powder use had to be