“Persistent organic pollutants (POPs) are synthetic organic chemicals that have wide-ranging human and environmental impacts (see Chapters 2, 3 and 6). In the late 1970s, studies of the North American Great Lakes highlighted the existence of older, obsolete chlorinated pesticides (so-called legacy chemicals) in sediments and fish (PLUARG 1978). As regulations curtailing their use were implemented, chemical levels have declined in some water systems since the early 1980s (see Chapter 6) (see Box 6.28). Similar declines have since been observed in China and the Russian Federation (see Figure 4.10). The estimated production of hazardous organic chemical-based pollutants in the United States by industry alone is more than 36 billion kilogrammes/ year, with about 90 per cent of these chemicals not being disposed of in an environmentally responsible manner (WWDR 2006). The chemicals in pesticides can also contaminate drinking water through agricultural run-off. There is growing concern about the potential impacts on aquatic ecosystems of personal-care products and pharmaceuticals such as birth-control residues, painkillers and antibiotics. Little is known about their long-term impacts on human or ecosystem health, although some may be endocrine disruptors. Some heavy metals in water and sediments accumulate in the tissues of humans and other organisms. Arsenic, mercury and lead in drinking water, fish and some crops consumed by humans have caused increased rates of chronic diseases. Marine monitoring conducted since the early 1990s in Europe indicates decreasing cadmium, mercury and lead concentrations in mussels and fish from both the northeast Atlantic Ocean and Mediterranean Sea. Most North Sea states achieved the 70 per cent reduction target for these metals, except for copper, and tributyltin (EEA 2003). Although occurring in some inland locations, such as the Upper Amazon, oil pollution remains primarily a marine problem, with major impacts on seabirds and other marine life, and on aesthetic quality. With reduced oil inputs from marine transportation, and with vessel operation and design improvements, estimated oil inputs into the marine environment are declining (UNEP-GPA 2006a) (see Figure 4.11), although in the ROPME Sea Area about 270 000 tonnes of oil are still spilled annually in ballast water. The total oil load to the ocean includes 3 per cent from accidental spills from oil platforms, and 13 per cent from oil transportation spills (National Academy of Sciences 2003). Despite international efforts, solid waste and litter problems continue to worsen in both freshwater and marine systems, as a result of inappropriate disposal of non- or slowly degradable materials from land-based and marine sources (UNEP 2005a).”

4.5 Beach or Coastal Modification and Implications

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