Shipping is the least environmentally damaging form of commercial transport and, compared with land-based industry, is a comparatively minor contributor to marine pollution from human activities. There has been a substantial reduction in marine pollution over the last 15 years, especially with regard to the amount of oil spilled into the sea, despite a massive increase in world seaborne trade.
Sea transport is one of the least environmentally damaging modes of transport and, when compared with land-based industry, is a comparatively minor contributor to marine pollution from human activities. It is estimated that land-based discharge (sewage, industrial effluent and urban/river run off etc.) and atmospheric inputs from land industry sources account for some 77% of marine pollution generated from human activities. In contrast, maritime transport is only responsible for some 12% of the total (see graphic). However, these United Nations estimates were produced in 1990 and the proportion of marine pollution that can be attributed to shipping is now thought to be lower than 10%.