Organic carbon and pesticide pollution in a tropical coastal lagoon-estuarine system in Northwest Mexico

The Altata-Ensenada del Pabellon system (similar to 360 km(2)) comprises three inland lagoons, a coastal lagoon, and a bay. Inland is ail important irrigation district (similar to 330,000 ha). Agricultural drains and two sugar cane mills wastewaters are discharged into the system. Particulate organic carbon in water varied from 0.5 to 6.1 mg C/l. Organic carbon mean concentration (mg C/g dw) in sediments was 22.6 in the bay, 92.6 in the coastal lagoon, and 179.6 in the inland lagoons. Organochlorine pesticides (OCs) mean total concentration (ng/g dw) was 59.13 for inland lagoons, 35.60 for coastal lagoon, and 9.08 for the bay. A significant correlation was found between organic matter and OCs.