Sources of waste
Over the past three decades, much of the attention in dealing with ocean and coastal environmental problems focused on point sources of pollutants, including oil from tankers, sewage from municipal and hotel pipes and even radioactivity from nuclear power stations.
More recently marine scientists have begun to look at more diffuse sources of contamination, including sources that deliver a broad range of pollutants and contaminants. Agriculture, forestry, extractive industry, urban development and many other sources all contribute large quantities of solid waste, sediments, nutrients and toxic pollutants. Rivers and streams are a major transport route for these materials to the oceans, but atmospheric deposition is also playing a role, making clear the linkages between human and ecosystem health on land, in the air and at sea.
It is critical to assess all possible sources of waste, and to realise that many human activities from industry to agriculture to activities in the home each contribute a broad array of wastes. For example, wastewater can come from any location connected to the sewerage system, e.g., homes, schools, sporting, facilities, shops, business, industry, and parks. Until we understand and begin to address all sources of waste then our efforts in one particular sector may be undone by increases in waste from another.