Pollution
Pollution is mainly caused by discharge of municipal and industrial solid waste and wastewater, run-off from agricultural fields, and maritime transport (especially of hazardous substances), as well as oil and gas extraction, refining and transport. Regional capacity for wastewater treatment is low; some 98 per cent of domestic wastewater is discharged into the northeast Pacific and 90 per cent into the wider Caribbean without treatment (UNEP 2001).
| Fish catch (million tonnes): Latin America and the Caribbean |
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Regional fish catch peaked in 1994 but collapsed later as a result of a strong El Niņo event Note: includes inland fisheries but excludes molluscs, crustaceans and aquaculture Source: compiled from Fishstat 2001 |
The effects of pollutants from land-based activities are exacerbated in large watersheds, and in turn may affect distant states. The transboundary effects of five major watersheds are especially notable: the Mississippi, the Amazon, the Plata, the Orinoco and the Santa Marta. Satellite images have shown large sediment discharges from coastal rivers and some large islands travelling across thousands of kilometres of ocean. During a fish kill episode in the Windward Islands in February 2000, pathological bacteria were detected that previously had been reported only in continental freshwater systems (Caribbean Compass 1999). It was suggested that the pathogens had been transported in sediments originating in floods in the Orinoco basin.
Maritime transport is a significant source of coastal and marine pollution in the region especially the release of oil through dumping of bilge water and tank rinsing. Other threats from maritime transport include discharge of sewage, garbage and hazardous chemicals, and introduction of exotic or invasive species to new areas through loading and off-loading of ballast water.
The ports in the region are the second most important destination for containerized goods from the United States, and the Panama Canal is a principal link for global maritime trade. Between 1980 and 1990, maritime transport in the region increased from 3.2 to 3.9 per cent of global trade, and significant increases are expected to continue as a result of trade liberalization and privatization of regional ports (UNCTAD 1995). Without counter measures, environmental problems related to maritime transport are expected to worsen in the future.
The marine and coastal areas of Latin America and the Caribbean are among the most productive petroleum-producing areas in the world. The most important pressure on the marine and coastal environment in specific localities is the risk of oil spills from oil and gas exploration, production and distribution systems. The world's largest recorded oil spill was the Ixtoc submarine oil blow-out in the Bay of Campeche, Mexico, on 3 June 1979 with a total estimated outflow of oil greater than the volume from the Exxon Valdez spill. In 1999 and 2001, significant coastal spills and pipeline ruptures in Brazil and Colombia caused both active public concern and new restrictions to control future spills. All oil and gas exploration operations have the potential to cause severe damage to the coastal and marine environment as a result of large and small spills, and chronic leaks.
