Demographic and Geographic Patterns of Cetacean-based Food Product Consumption and Potential Mercury Exposure within a Caribbean Whaling Community

Abstract

Background: Exposure to mercury (Hg) through the consumption of seafood is a major public health concern. The tissues of high trophic level marine organisms, such as cetaceans, often contain high concentrations of Hg compared to lower trophic level species. The archipelagic Caribbean nation of St. Vincent & the Grenadines supports two related whaling operations, which produce food from cetaceans for human consumption. A recent study reported that Hg concentrations in tissue samples from one of these whaling operations exceed recommended consumption limits. Our objective was to determine the role of cetacean-based food products in the diet of the Vincentian population as a proxy for exposure to MeHg. Methods: We conducted interviews with 921 members of the Vincentian public. We asked questions about the types of food consumed, frequency of consumption, and quantities consumed. Based upon provisional tolerable weekly intake (PTWI) guidelines for methylmercury (MeHg) from the Food and Agricultural Organization (FAO) and the World Health Organization (WHO), we determined safe weekly consumption amounts for specific cetacean-based food products, based upon reported consumption patterns. Results: We found cetacean-based food products to be included in the diet of 77.4 percent of respondents. Respondents’ gender and geographical home region are the most predictive attributes for cetacean-based food product consumption, whereas socioeconomic status and age play a minor role and no role, respectively. Frequency and amount of consumption vary, but generally exceed calculated safe weekly consumption amounts. Conclusions: The consumption of cetacean-based food products by members of the Vincentian public may represent a public health risk, as data indicate that a large portion of the population may be exposed to concentrations of MeHg in excess of recommended limits. Any potential action to address this risk is likely to be most effective if targeted toward the specific high-consumption population segments identified by our study.