A recently published study indicates that the concentration of mercury found in North Pacific commercial fisheries is climbing at a rate of 4% yearly, and this is a reflection of the amount of mercury in the waters of the North Pacific oceans.
“The take-home message is that mercury in tuna appears to be increasing in lock-step with data and model predictions for mercury concentrations in water in the North Pacific,” said lead author Paul Drevnick, from the University of Michigan Biological Station and School of Natural Resources and Environment.
The model predictions were based on the atmospheric mercury release caused by smelting and the widespread burning of coal for power among other industries, and compared with historical records available on yellowfin tuna or Thunnus albacores in Hawaii over the past 50 years. The resulting data is that mercury concentrations continue to rise with no signs of abating since the industrial revolution.
“This confirms that mercury levels in open ocean fish are responsive to mercury emissions,” Drevnick added.
And at the rate of increase, the levels of industry-emitted mercury could double in concentration and the toxic metal overwhelm the Pacific by 2050, the researchers said. The Minamata Convention on Mercury held last September at the UN General Assembly where 120 countries vowed to combat the threat of mercury poisoning on a global scale would be defeated unless of course immediate steps are taken to arrest the situation.
The convention was designed to have nations working together to reduce industrial mercury emissions and prevent another tragedy like the one that occurred to the Japanese city of Minamata in 1956, which resulted in at least 54 cases of mercury poisoning. Most of those cases resulted in death or devastating cognitive impairment within the year.
“Future increases in mercury in yellowfin tuna and other fishes can be avoided by reductions in atmospheric mercury emissions from point sources,” Drevnick and his colleagues pressed, stressing that aside from pursuing ways to reduce mercury pollution via safe industrial practices, regulative attention should be brought to atmospheric emissions, namely those from gold smelting and coal burning.