Untitled

Abstract

Oysters of Urías lagoon (NW M exico) were collected every second month from November 2012 to September 2013, to determine the variations of their mercury (Hg 2+ ) content and assess their suitability for human consumption. Concentrations were significantly higher in November than in M arch and M ay, which indicates that variability does not depend on the alternation of dry and rainy seasons, and is probably related to the reproductive cycle of this species. In view of the low apparent seafood consumption in M exico and given the low mean H g 2+ concentrations (0.07-0.26 µg g -1 , dw), consumption of this oyster does not seem to pose risks to the largest part of the population, but the local fishing communities are the ones most likely to be at risk, because of their higher seafood consumption.