Health risks due to the presence of lead (Pb) and copper (Cu) in a coastal area of Tabasco, Mexico

Aquatic environments are being impacted in Mexico and worldwide due to anthropogenic activities. Since some metals are accumulated in the environment while others are magnified in the chain trophy, they represent a risk to organisms living there as well as human settlements established in the zone. The objective was to identify the concentration of lead (Pb) and copper (Cu) in the water of Barra de dos Bocas located in Tabasco, Mexico. The water sampling was done at depths of 1, 3 and 5 m, obtaining a weekly sample of 500ml during the period between January and May 2007. The water samples were treated and analyzed according to Mexican Norm NMX-AA-SCFI-051-2001 using atomic absorption. In addition, pH and EC were determined. The Pb concentration varied in the range of 0.123-0.378±0.062 mg L -1 . The Pb levels were higher than those established in the Ecological Norm NOM-001-ECOL-1996, which indicates a Maximum Permissible Level of 0.2 mg L -1 . The Cu levels were within a range of 0.004-0.258±0.023 mg L -1 which is below the Maximum Permissible Level indicated in the norm of 0.4 mg L -1 . The Pb may pose a problem to the aquatic