Human activities have contributed significantly not only to global warming but have also increased the levels of mercury in the ocean. A recently published report in nature magazine has showed that the levels of mercury have sought a threefold rise in some region because of human actions. Activities like mining and fossil fuel combustion have attributed to high levels of mercury.

Mercury is known as a toxic trace metal that accumulates in aquatic organisms and poses serious threats to human beings. The total amount of anthropogenic mercury in the global ocean has been estimated by the new study conducted by American researchers from Woods Hole Oceanographic Institution.

Since the beginning of the Industrial Revolution, the levels of mercury in thermocline waters have increased by nearly 150% and the mercury content of surface waters has gone up by more than three times, said the study. Almost 66% of the mercury is present in water shallower than 1,000 meters.

The findings hold significant importance because they provide insight into how inorganic mercury is converted into toxic methyl mercury at depths and it affects marine food webs.

"It would seem that, if we want to regulate the mercury emissions into the environment and in the food we eat, then we should first know how much is there and how much human activity is adding every year", said WHOI marine chemist Carl Lamborg.

As of now, researchers have no way out to test a water sample for understanding the difference between mercury that comes from pollution and mercury that came from natural sources.