How does mercury enter the sea?
Oftentimes, the elemental mercury doesn’t jeopardize the health of living creatures as it’s easily eliminated from the organism. Scientists are alarmed by the accumulation of its form – methylmercury that penetrates into tissues. Let’s see how mercury transforms into methylmercury. According to scientists, there two main sources of mercury the sea:
- Natural – while erupting, volcanoes release organic mercury into the air. Nearly 60 volcanoes activate each year. For example, the volcanic gases of Mount Etna contribute almost 20 tons of mercury per year.
- Human-caused - a lot of inorganic mercury gets into the soil due to human activities such as the burning of fossil fuels that releases approximately 160 tons of mercury per year or as the result of mercury landfills.
The mercury accumulates in the soil and consequently gets into the groundwater. As you might have guessed, in the end, it enters the sea. The most important thing about this is that methylmercury is formed only from inorganic mercury by the action of aquatic microorganisms and microbes.
Why is it dangerous?
According to recent research conducted at Umeå University in Sweden, methylmercury is quickly absorbed by animals and humans. It is very toxic and causes kidney deceases, including kidney failure, or birth defects. In the mid-XX century, Minamata City, Japan, was hit by an outbreak of a strange and deadly decease that included the following symptoms:
- Damage to hearing/speech
- Loss of peripheral vision
- Numbness of limbs
- Muscle weakness
It turned out that Minamata decease was caused by mercury poisoning as the result of Chisso Corporation’s massive dischargers of methylmercury into the coastal waters. By and large, methylmercury diffuses into phytoplankton that is consumed by protozoa that, in its turn, is consumed by zooplankton. Methylmercury level tends to increase up the food web.
Thus, to avoid mercury poisoning, the U.S. Environmental Protection Agency and the Food and Drug Administration recommends to cut back on seafood – especially, limit the consumption of top predator species such as swordfish, shark, tuna, etc. Description: Since the beginning of the Industrial Revolution the concentration of toxic mercury in sea life has increased more than threefold! Read our new article and find out why the consumption of seafood can ruin your health!