more detailed background approach to the design of guidance intended for the four target populations.
A decision tree or other decision representation is another way of depicting the consumption guidance listed above. This kind of diagram highlights the variables that group consumers into specific target populations who face different benefits and risks and who should receive tailored advice. In the committee’s judgment, the variables that distinguish between target populations facing different benefit-risk balances, based on existing evidence, are age, gender, and pregnant or could become pregnant, or breastfeeding. A fourth distinguishing variable explored by the committee was risk of cardiovascular disease. However, as noted above, the committee believes the evidence is insufficient to warrant separate guidance to this group beyond that which would be offered based on age, gender, and pregnancy or breastfeeding status. These three variables, as they apply to the target population groups, are arrayed in a decision pathway, shown in Figure 5-2, that illustrates the committee’s final analysis of the balance between benefits and risks associated with seafood consumption.
The committee believes that it is fundamentally important to acknowledge that benefit-risk analysis as conducted here will always have limitations related to the availability of data on and evaluation of benefits and risks. For example, here the committee relied on data that contain a variety of uncertainties. In the case of seafood consumption, the potential for an adverse health effect from exposure to a contaminant is presumed to depend upon, among other things, differences in prior exposure levels as well as differences in sensitivity to toxicants among individuals. Likewise, persons may receive variable benefits, including no benefit, from nutrients that are found in higher concentrations in seafood than in most other foods, i.e., EPA/DHA and selenium. Those already at low risk for cardiovascular disease, for example, may see little cardiovascular benefit from seafood consumption. Furthermore, it is difficult to obtain information regarding when sampling occurred, the number of samples taken, and the methodology used to identify and quantitate specific nutrients over time, resulting in uncertainty about the variability of nutrient levels in seafood. Finally, no two samples of seafood, either from the same species or from different tissues in the same seafood will contain the same level of either nutrients or contaminants.
In the committee’s judgment, these uncertainties may reduce the applicability of the guidance to a specific person, but the general guidance for safe seafood consumption applies to most persons in a category. The