Metals and shrimp aquaculture in Mexico

In Mexico, shrimp aquaculture has been mainly developed in the coastal areas of the Northwestern states where it competes with other human activities, mainly agriculture and animal husbandry, as well as with the related industries. These activities, as well as the urban settlements of the region, generate large quantities of pollutants among which, at least in certain areas, heavy metals have been detected as possible sources of concern. This paper synthetizes the information available to date on the levels of some metals present in the coastal areas of Northwestern Mexico where a high number of shrimp farms has been established, as well as on shrimp farm sediments and on cultured and wild- shrimp tissues. The effects of some metals are examined in terms of acute toxicity levels, sublethal effects, damages at the histological, systemic and genetic levels determined for the most important species for Mexican shrimp aquaculture, Litopenaeus vannamei. Other actual or potential species of interest for the regional aquaculture have also been considered.