Mercury levels in the ocean are dangerously high. According to a study published in Nature this Wednesday, humans are poised to produce levels of mercury in the next 50 years that will surpass the amount produced in the past 150 years. When scientists conducted testing on the ocean to determine the presence of the element, they expected to account for the 350,000 tonnes produced by human activity. They found between 60,000 and 80,000 tonnes, a considerable amount. However, mercury emissions from human activity are known to be much higher than the levels found in the ocean would seem to indicate.
Since the Industrial Revolution, large amounts of mercury have been emitted due to human activity. Much of this has been as a by-product of acts like mining, making cement and burning coal. Although mercury occurs naturally, it is poisonous if ingested in large amounts. It binds with organic materials and destroys them, making mercury a danger to marine life.
The study looked at phosphate, which acts similarly to mercury, to determine the level of mercury in the ocean. The ratio of phosphate to mercury was measured in thousands of water samples, in areas deeper than 3,300 feet. Findings showed that mercury levels have increased by 10 percent since the industrial revolution. The ocean, however, seems to have a way to minimize the effects of toxicity levels.
Carl Lamborg, marine geochemist at Woods Hole Oceanographic Institution and co-author of the study, says that some of the element is being hidden in the depths of the ocean. The ocean’s circulation patterns move mercury from shallower waters into deeper waters. This act regulates the levels of toxicity that affect marine life. However, the ocean’s ability to compensate is being exhausted. Consequently, the levels of mercury in shallow water will get higher as emissions continue to be pumped into the ocean.
Deep water is not the only place where mercury could be hiding. Lamborg speculates that mercury could be in the soil found around mining sites, a large source of the element. There are other findings that support this possibility. Helen Amos of Harvard University says that mercury from mining sites is ending up in nearby sediments. Rivers are believed to be carrying an estimated 90 percent of the substance to these areas. Such high levels of mercury can destroy a town. In the past, unregulated mercury production has caused devastating effects on humans.
In the mid-20th century, Minamata Bay in Japan was releasing dangerous levels of mercury into the water. Thousands of locals ate enough seafood overtime that they, and other animals, became very ill. This level of toxicity had never been seen before. As a result, when someone shows high levels of toxicity in their body, it is refered to as Minamata disease. Over 900 people died from contamination and approximately 2 million were affected, stripping them of their health and leaving some permanently disabled. The effects were so devastating on the human body that it continued to infect the infants born of contaminated mothers.
If mercury emissions get much higher, the level of toxicity in the ocean will have adverse effects on marine life and all who interact with it. Still, scientists are hopeful. Lamborg believes these new findings are an opportunity for humans to have a positive effect. Now that scientists are aware of the levels of mercury emission and how much is being added annually, they are in a better position to regulate what ends up in the environment.
By Kamille Dawkins