Explain the cause of high levels of mercury in marine fish

Mercury content - an organic compound that can cause brain damage and severe nervous system - has increased by 23% in cod and 27% in bluefin tuna caught in the Atlantic Ocean.

Climate change and overfishing are increasing mercury levels in cod and tuna . This can cause neurological disorders syndrome in young children and babies whose mothers eat fish during pregnancy.

Research by Harvard University scientists has been published in Nature.

Mercury content - an organic compound that can cause brain damage and severe nervous system - has increased by 23% in cod and 27% in bluefin tuna caught in the Atlantic Gulf of Atlantic in about 3 decades.

Climate change and overfishing are increasing mercury levels in tuna.(Artwork: Reuters).

Research co-author, professor of environmental chemistry at Harvard University Elsie Sunderland School of Medicine said mercury is extremely toxic during the third trimester of pregnancy when the fetal brain is rapidly developing.

Pregnant women have long been advised to avoid eating food made from swordfish and shark meat due to the high mercury content, but cod is the type of fish that experts believe contains a lot of nutrients and riches. Protein can support fetal growth.

However, Professor Sunderland said that consumers should not be too scared after reading this study, because seafood is still a source of nutritious and healthy food.

Researchers just want to prove that climate change can have a direct impact on food, followed by human health . not only extreme weather, floods and sea level rise. .

Warming seawater increases the energy needs of small fish, so they eat more bait containing mercury. These small fish are then eaten by tuna, making the mercury content accumulate in the tuna.

Overfishing of herring and sardines also changes the eating habits of Atlantic cod , forcing them to fill up herring and lobster, which have high levels of mercury.

According to the United Nations Food and Agriculture Organization, global fish consumption has doubled since the 1960s of the last century to a record of 20.2kg / person / year, with 30% of the ocean being exploited. excessive seafood.

Researcher Sunderland stressed the situation may be more serious in the US if US President Donald Trump reduced the limit of mercury emissions from thermal power plants, which were effective under his predecessor Barack Obama.

The 2018 study by Harvard University experts showed that coal-fired power plants are the leading mercury-containing source of gas in the US, accounting for 40% of total emissions.

This waste gas then infiltrates into soil and water and is eaten by marine organisms. Therefore, Sunderland researcher called for a reduction in mercury emissions, especially from coal-fired thermal power plants.

1. Mercury infection is 3 times more common than normal because the food is good but eating wrong will be dangerous
2. Sunlight affects the content of mercury in fish