ùñIndustry, agriculture, and urban waste are sources of pollutants that can contaminate rivers, lakes, the oceans, and our water supply.ñ
Mercury, cadmium, pesticides, and herbicides are all contaminants of fresh water. Pollution and the proliferation of algae remove oxygen from rivers, resulting in fish dying from suffocation in hot weather. Groundwater would seem to be a source of clean water for human consumption but agricultural fertilizers and manure have also polluted some groundwater reservoirs.
Phosphates and nitrates, used in fertilizers, are particularly dangerous. Phosphates are essential for the growth of all living beings, but when the levels present in waste water are too high, they cause excessive growth of algae, which then suffocates the fauna and flora present. Nitrates contained in the nitrogenous fertilizers used in agriculture infiltrate groundwater reservoirs and reach rivers, threatening the quality of our drinking water. These nitrates can be a serious threat to health, especially to young babies and pregnant women.
~The sea as a refuse dump~
Oil slicks, chemical pollution, and industrial and agricultural waste all damage marine ecosystems. Up to 80 per cent of waste water from many large European towns is pumped into the sea without prior treatment. Unfortunately, the North Sea and the Mediterranean are high on the list of the most polluted seas. Every year, between Marseilles and Nice in southern France alone, 1 million tonnes of oil-based products, 120,000 tonnes of mineral oil, 60,000 tonnes of detergent, 240,000 tonnes of chlorine, and 100 tonnes of mercury are dumped into the sea.
Although some European Union countries are endeavouring to install sewage plants, many other Mediterranean countries continue to discharge their effluents into the sea without prior treatment. The North Sea is relatively shallow and small in size and is unable to dilute pollutants efficiently. Several major European rivers, such as the Rhine and the Elbe, are heavily polluted and discharge their polluted waters into the North Sea. The North Sea has also been polluted by spills and leaks from several of the 150 platforms exploiting its oil reserves. x 2
