O MERCÚRIO EM CETÁCEOS (MAMMALIA,CETACEA): UMA REVISÃO.

Abstract

MERCURY IN CETACEANS (MAMMALIA, CETACEA): A REVIEW. Mercury (Hg) is one of the
most studied elements concerning to its ecotoxicological aspects. Its main absorption route in marine vertebrates
is through diet which, along the low rates of excretion, leads to the increase of the element's concentrations
through the trophic chain. As top predators and presenting great longevity, cetaceans end up exhibiting high
concentrations of the pollutant, with a long biological half-life in their tissues. Therefore, these animals are
frequently used as sentinels of the environmental health related to mercury. The present review approaches
the contaminant's body distribution, detoxification strategies and the possible influence of biological and
ecological parameters on the pollutant accumulation, also presenting data on hepatic contamination of several
species of cetaceans in different geographic regions. It has been observed similar concentrations in regions of
South and North Hemispheres as well as higher concentrations than the hepatic tolerance limit for mammals
(100-400µg/g wet weight) in the South Hemisphere and the Mediterranean.
Keywords: Mercury; cetaceans; bioaccumulation; biomagnification; detoxification.