The development of civilization has led to increased pollution of the world’s oceans. The situation began to worsen around the middle of the 20th century due to the development of the chemical and oil refining industries. Today we can distinguish several types of pollution;
Physical. Garbage, and especially plastic, which hardly decomposes, is a huge problem for the ecology of the oceans. Millions of tons of plastic waste drift across the surface of the world’s oceans, with experts estimating that 80 percent of this garbage has entered the ocean from the land. The trash harms more than 250 species of marine animals and birds and releases toxic substances into the water;
Biological. Pollution of the oceans by alien bacteria, various microorganisms, and organic waste steadily disturbs the fragile ecological balance;
Chemical. Chemicals and heavy metals are used in a wide variety of industries. Together with sewage, they enter the ocean and in huge quantities. Mercury, which also accumulates in living organisms, and pesticides are especially dangerous. But not only big factories are responsible for chemical pollution of the ocean: a lot of chemicals also get into the water from the sewers because we constantly use synthetic detergents;
Oil. Oil and petroleum products are the main sources of pollution in the world’s oceans. Oil gets into the water due to manufactured disasters, tanker wrecks, and well drilling, but quite a few oil products are also dumped by ordinary marine transport. Oil spills kill large numbers of marine animals, fish, and birds and prevent regular heat exchange between water layers;
Thermal. Wastewater that is discharged into the oceans by power plants locally raises the temperature of the water, leading to the mass death of creatures unable to survive at such high temperatures. It disrupts food chains and leads to the extinction of many species. At the same time, some species of algae begin to multiply too actively, resulting in water blooms;
Radioactive. The ocean has long been a dumping ground for radioactive waste. Research estimates that the world’s oceans today contain an incredible number of radioactive substances.
Oil and petroleum products, sewage, chemicals, heavy metals, radioactive waste, mercury, and plastic are the primary sources of pollution in the world’s oceans.
However, it is difficult to say which type of pollution is the most dangerous – all of them, to some extent, affect the planet’s ecosystem, including humans. For example, toxins can accumulate in the tissues of commercial fish, making them unfit for consumption. For instance, tuna from the Adriatic Sea often have very high mercury levels, and fish from northern seas often have elevated levels of lead. Poisoning with seafood containing toxins can be fatal: Minamata disease, caused by poisoning with seafood high in mercury, killed at least 70 people.
The blooming of coastal waters caused by the dumping of organic waste and fertilizers makes them unfit for fishing, as the fish in the blooming water die. It deprives gourmets of seafood delicacies and takes jobs away from hundreds of thousands of people. Against this backdrop, turning paradisiacal beaches into stinky dumps seems like the least of the problems.
Ways Out: World Class
All this cannot but cause concern, so many countries have long been attempting to remedy the situation or minimize the damage that human activity causes to the world’s oceans.
For example, France passed a law regulating the location of water intake and discharge points for factories and plants; the sea coast is regularly patrolled by helicopters, whose task is to monitor tanker discharges. In addition, a high-tech and effective solution to the dumping problem was found in Sweden – the tanks of each tanker are tagged with particular isotopes, so scientists analyzing oil slicks can always determine from which particular vessel the dumping took place.
On the initiative of the UN has been signed a number of major international agreements, which imply proper and clear regulation of the use of resources of the oceans, oil extraction, etc., as well as the International Convention, which provides for the liability of companies and compensation for damages, which is associated with the transportation of hazardous and harmful substances by the sea in 1996 and others.