How mercury gets into mining and why it needs to be banned from Brazil

Metal contaminating Indigenous people is highly toxic and needs more control in the production and trade chain

Translated by: Ana Paula Rocha

Brasil de Fato | Londrina (Paraná state) |
Mercury enters Brazil mainly through the country’s frontiers with neighboring countries in the Amazonian region. Pregnant Yanomami women are the most vulnerable group to mercury contamination, says Fiocruz - Fernando Frazão/Agência Brasil

Dario Kopenawa, a leader in the Yanomami Indigenous Land, describes a serious public health situation. "[In Indigenous communities] Children are being born without arms. That’s already happening. Women suffer from urinary tract infections. They have neurological problems, which make people a bit upset. Some children have already died," he told Brasil de Fato in April 2024.

According to the Oswaldo Cruz Foundation (Fiocruz, in Portuguese), the cause of congenital malformations in babies is mercury, a heavy metal used in illegal gold mining in the Amazon. Illegal miners use it to purify the ore they extract from the soil or the bottom of rivers. Between 2018 and 2022, 185 tons of mercury may have been used in illegal mining in Brazil, according to a recent study by the Escolhas Institute.

In the Yanomami Indigenous Land, the federal government has managed to expel most of the illegal miners, but armed groups remain. Once again, the territory was invaded after the airspace over the region was reopened.

Rafael Giovanelli, a researcher and project manager at the Escolhas Institute, points out that China is the world leader in mercury production. The metal enters Brazil mainly through its frontiers with neighboring countries in the Amazonian region.

Also called azougue, mercury is commonly traded on WhatsApp groups. Without much effort, Brasil de Fato found countless ads like the one below, which was in a virtual group of illegal miners from Pará, northern Brazil, the state with the largest production of illegal gold in the country.  

In a WhatApp group of illegal miners, people announce azougue, another name for mercury/ Printscreen

"Bolivia is one of the main importers of mercury, but it doesn't have consistent gold production. In our analysis, the amount of mercury entering the country does not correspond to its gold production. Peru is also a major exporter of mercury, selling it to the rest of the world. Guyana has a considerable amount [of mercury] circulating within its borders," explained Giovanelli.

Mercury trade controls need to be improved

Brazil's mercury control mechanisms are rigorous in theory, but in practice, they have many weaknesses. The Brazilian Institute for the Environment and Renewable Natural Resources (Ibama, in Portuguese) requires traders to register and obtain specific permits for each commercial operation of the metal.

But inspections are sporadic and verification of the origin and destination of mercury is inefficient, allowing large quantities to circulate illegally. In addition, the Amazon's international border is vast. Entrusted to the military by the Constitution, inspection in these areas deals with the tip of the iceberg. 

"Ibama has a register that maps some links in the chain, but not all of them. And there isn't such a strong traceability mechanism, with a document that accompanies the substance," says Giovanelli.

To solve the problem, Ibama is reformulating its control measures on the purchase and sale of mercury. The environmental agency said the new rules will come into force soon. Documents will be required at each stage: transportation, use and storage. Proving the legal origin of the mercury will be a way of preventing the substance from falling into the hands of illegal miners.

Serious contamination affects the mother and baby

According to the Oswaldo Cruz Foundation (Fiocruz, in Portuguese), mercury is extremely toxic, and its effects on human health are devastating. It enters the human body mainly through contaminated water and food, such as fish from rivers polluted by mining. Once in the body, it accumulates in the tissues, mainly affecting the central nervous system, and can pass from mother to child during pregnancy.

Paulo Basta, a doctor and researcher at Fiocruz has seen the effects of mercury contamination up close. He visited the Yanomami Indigenous Land and found the heavy metal in the bodies of all Indigenous individuals examined.

"When women are massively exposed to mercury, it can compromise their reproductive lives. They may not be able to carry the pregnancy to term and have repeated miscarriages. When they do give birth, the child is often born with neurological syndromes, cerebral palsy or congenital malformations. So, these are serious problems," she said.

Severe cases like these, however, are rarer. Most commonly, the disease progresses slowly and insidiously.

"What we see most often are children who are born apparently normal. But as time goes by, you notice some delays in neurodevelopmental milestones, for instance, a delay in holding up the head, sitting, crawling, standing, taking the first steps and speaking the first words. When the child reaches school age, you realize they have learning difficulties," Basta explains.

Colombia banned mercury and Brazil needs to do the same

Escolhas Institute argues that Brazil should follow the example of Colombia, which has banned the use of mercury in mining, or the cosmetics industry, which has also stopped it.

"We have to move towards the complete elimination of mercury in the whole industry, but especially in mining, because it is causing very serious consequences for the environment and for the people," concluded Rafael Giovanelli.

Edited by: Nathallia Fonseca