Elevated Accumulation of Parabens and their Metabolites in Marine Mammals from the United States Coastal Waters

The widespread exposure of humans to parabens present in personal care products is well-known. Nevertheless, little is known about the accumulation of parabens in marine organisms. In this study, six parabens and four common metabolites of parabens were measured in 121 tissue samples from eight species of marine mammals collected along the coastal waters of Florida, California, Washington, and Alaska. Methyl paraben (MeP) was the predominant compound found in the majority of the marine mammal tissues analyzed, and the highest concentration found was 865 ng/g (wet weight [wet wt]) in the livers of bottlenose dolphins from Sarasota Bay, FL. 4-Hydroxybenzoic acid (4-HB) was the predominant paraben metabolite found in all tissue samples. The measured concentrations of 4-HB were on the order of hundreds to thousands of ng/g tissue, and these values are some of the highest ever reported in the literature. MeP and 4-HB concentrations showed a significant positive correlation (p < 0.05), which suggested a common source of exposure to these compounds in marine mammals. Trace concentrations of MeP and 4-HB were found in the livers of polar bears from the Chuckchi Sea and Beaufort Sea, which suggested widespread distribution of MeP and 4-HB in the oceanic environment.