Persistent organochlorine pesticides (POPs) in coastal lagoons of the subtropical Mexican Pacific

Sediment samples were collected in the Chantuto-Panzacola and Carretas-Pereira lagoon systems of Chiapas, Mexico, and concentrations of persistent organochlorine pesticides (POPs) were measured. Also analyzed were the percentage of organic carbon and the type of sediment. Results showed that the highest levels of POPs were found in the Carretas-Pereira lagoon, especially for heptachlor, heptachlor epoxide, and aldrin. The most abundant compounds in the Chantuto-Panzacola system were endosulfan II, p,p'-DDE, and heptachlor epoxide. Peak concentrations of the different POPs were noted in different seasons, which were related to cropping patterns. In white shrimp Penaeus vannamei and brown porgy Lutjanus novemfasciatus from both lagoons, the POPs were found to be degraded to concentrations below the regulated limits for human consumption.