Persistent organic pollutants in sediment cores of Laguna El Yucateco, Tabasco, Southeastern Gulf of Mexico

Resumo

Information is presented on the content of polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) in sediment cores collected in the coastal ecosystem of Laguna El Yucateco, located in the tropical southeastern Gulf of Mexico. The ecosystem lies in a region where the human population is socially and economically limited, and it is subjected to great environmental pressure derived mainly from the oil industry. The vertical profiles data show that concentration of the various persistent organic pollutants (POPs) does not present a homogeneous pattern, making evident that the levels of these pollutants depend strongly on anthropological discharges from industrial, urban and farming sources, as well as on those originated by sanitary control measures for the prevention of tropical diseases such as malaria. Potentially carcinogenic compounds were found, including benzo(a)pyrene, aldrin and polychlorinated biphenyls congeners that have been classified as endocrine disruptors. The magnitude of the concentration of persistent organic pollutants is alarming, as values were above the sediment quality criteria established to prevent damage to benthic organisms. Coastal sediments also represent an environmentally risky secondary source of pollutants.