PAHS IN SEDIMENTS FROM COASTAL LAGOONS OF GULF OF MEXICO

摘要

In this study a determination of the concentrations of 15 polycyclic aromatic hydrocarbons (PAH) in surface sediments from Salada, El Llano, La Mancha and Mandinga Lagoons, Veracruz was made during the period 1997 to 1999; these compounds were evaluated by means of gas chromatography using capillary columns of high resolution and flame ionization detection (GC-FID). The statistical results shown that differences in total concentration of PAHs during dry and rainy seasons were no significatives (p=<0.05), as well as the differences related with spatial distribution of PAHs. This is probably due to the shallowness and size of these lagoons, which are very small compared with others systems in the Gulf of Mexico. Comparison of the present results to those from other coastal systems along the Gulf of Mexico revealed that Mandinga lagoon is an area with high PAHs inputs mainly of pyrogenic origin, coming from the inflows of the rivers crossing industrial areas, oil and gasoline spills from fishing and tourism boats, the burning of surrounding vegetation and atmospheric transport. The presence of compounds made up primarily of 4 and 5 benzene rings, proves the hypothesis that the origin of the PAHs determined in all these lagoons is mainly anthropogenic. Besides the presence of 2-ring aromatic compounds in Mandinga lagoon confirms recent petrogenic inputs.