Mercury river dolphins are poisoned with mercury

Conservationists found alarming levels of mercury poisoning in the Amazon river dolphins population due to illegal gold mining.

In a study recently conducted by the World Wide Fund for Nature (WWF), experts found 46 Amazon river dolphins were contaminated with mercury at levels 1.5 times normal. They are found in major river basins in Brazil, Colombia, Venezuela, Bolivia and Peru.

Amazon river dolphins.(Photo: Newsela).

Marcelo Oliveira, a spokesman for WWF, said the main reason was the illegal gold mining , in which mercury is used to separate gold from other minerals. The most seriously polluted areas are the Orinoco river basin in Colombia and Venezuela.

However, gold mining is not the only problem.Mercury also exists naturally in the Amazon. The impact of deforestation and forest fires has spread this heavy metal element into the water environment and into the dolphin food chain, as well as small fish - their main food source.

Fish high in mercury is also a threat to nearly 20 million people living in the Amazon region, who will eventually eat the poisoned fish."Mercury can survive for up to 100 years in the food chain. That's a big problem , " Oliveira warned.

The Amazon river dolphins, also known as the pink dolphins or Boutu , are endemic to freshwater fish in South America, living in the Amazon and Orinoco river systems. This is the largest river dolphins, can reach 2.5 m long and weighs 185kg. They are now listed as endangered in the Red List of the International Union for Conservation of Nature.

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