Sixty per cent of Earth population inhabits coastal lines of seas and oceans. This is why water bodies are the first ones to suffer from human activities. Pollute the oceans, and the planet will be dead within a year!

Large oceanic fish like tuna and marlins is not edible nowadays. The reason is the high concentration of mercury in its tissues. It is stored as an extremely toxic organic substance, methylmercury. Sources of mercury pollution are coal processing and chlorine production plants. Methylmercury is consumed by algae that feeds small fish, main forage for larger fish.

Oceanic streams capture plastic waste from our shores. There is an island made of plastic particles in the North Pacific that bears the name of the Great Garbage Patch. Its upper layers contain small suspended plastic pieces, and its bottom consists of larger particles. This island brings death to fish and marine birds. Partially, this waste is carried to the Hawaiian beaches.

Oil spills are a greater hazard to the environment than it seems. It's relatively easy to gather petroleum film from water surface. But there is no technology designed to get rid of aromatic hydrocarbons contained in crude oil. High concentration of these substances persists in the water for thirty years after the spill!

Acidification of the oceans is one of the global warming consequences. It is caused by high concentration of carbon dioxide in the water. All aftermath of this process is yet to be studied, however, it is well known now that high acidity leads to decay of structures composed of calcium carbonate – like corals and seashells.

Phosphorus and nitrogen pollution leads to uncontrollable growth of blue-green algae on the ocean bed. The algae consume all the oxygen dissolved in water, thus causing vast dead zones along the water column. Main cause of this pollution is careless farming: phosphates, nitrates and nitrites from fertilizers are washed off the fields by rainwater and carried to the oceans.

Deepwater mining sites are generally located near hydrotherms – underwater volcanoes. It is a modern way of extraction of iron, manganese, copper, cobalt, zinc, gold and silver. Although this method of extraction was invented recently, scientists say that it had already led to irreversible consequences, like death of deepwater creatures, toxic pollution and turbidity of all water column.

Noise pollution of the oceans remains a serious problem for most marine creatures like dolphins who are almost blind and perceive the world with ultrasound. Deepwater creatures don't have any eyesight at all, and sonar perception is all they have. Noise of passing vessels, seismic and survey radars choke the songs of the oceans!

Toxins in the oceans are an aftermath of industrialization that we now have to cope with. For examle, the bed of the Amur Liman is polluted with phenol dumped by Russian and Chinese plants. Some creatures have a particular ability to survive high toxicity levels. One of them is Chinese mitten crab, captured by commercial fisheries. Its meat may be very dangerous for human health.

Nuclear pollution of the oceans is trending the news ever since March 2011, the Fukushima meltdown in Japan. Due to large amounts of water radioactive elements didn't make it to Hawaii or Kurils. But there's no reason for optimism: commercial fisheries that operate relatively far from the Japanese Archipelago have already captured small fish polluted with dangerous amounts of cesium and iodine isotopes.