- Small-scale gold mining is the key driver of global mercury demand, according to a UN report on the highly toxic metal, with South America accounting for 39% of this demand.
- Hair samples taken from Indigenous communities in the Bolivian and Brazilian Amazonian regions showed mercury levels in excess of the safe limit prescribed by the World Health Organization.
- In Brazil specifically, mercury use has risen with the boom in illegal mining that has been largely overlooked — and in some cases even encouraged — by the government of President Jair Bolsonaro.
Artisanal gold mining is driving the global demand for mercury, with 2,058 metric tons of the toxic metal contaminating water, land and air every year, according to a recent report Mercury, Small Time Gold Mining and Human Rights.
Presented before the United Nations Human Rights Council on Sept.20 by Marcos Orellana, the UN’s special rapporteur on toxics and human rights, the report calls for an end to mining, exporting and trading mercury, as well as a ban on the use of mercury in small-scale gold mining.
“An estimated 10 million to 15 million people were directly engaged in small-scale gold mining in 2017, including an estimated 1 million child workers and 4.5 million women,” the report says. “It generates up to 20% of the global gold supply annually, equivalent to approximately 500 tons, with a market value of almost $29 billion annually.”
Orellana, who teaches international environmental law at George Washington University in the US, found that the demand for mercury used in small-scale gold mining stems from three key regions: South America (39%), East and Southeast Asia (37%), and sub-Saharan Africa (21%).
Most small-scale gold mining in South America is centered in the Amazon. In Brazil, it has gone “big scale.” According to MapBiomas, a research collective that tracks land use changes through satellite imagery, small-scale gold mining in 2018 overtook industrial mining in scale, covering 107,800 hectares (266,000 acres) in 2020, 94% of it in the Amazon.
The Intergovernmental Forum on Mining, Minerals, Metals and Sustainable Development (IGF) estimates there are more than 450,000 artisanal miners, or garimpeiros, in Brazil. More than 20,000 operate illegally inside the Yanomami Indigenous Territory alone.
Small-scale gold mining not only destroys vast areas of forests, leaving moon crater-like wasteland in its wake. The most devastating aspect, for both miners and people worldwide, is the use of mercury to extract the gold from the ores.
Also known as quicksilver, mercury is liquid at room temperature. When heated, it evaporates into the atmosphere or washes away into rivers, lakes and oceans, contaminating fish and thus entering the food chain.
The Minamata disaster
In the 1950s, mercury caused one of the 20th century’s most notorious industrial disasters, in the Japanese town of Minamata. A petrochemical company, the Chisso Corporation, had for years been dumping waste containing methylmercury in the local bay. This form of bacteria-bound mercury wound its way up the food chain, and eventually led to widespread deaths, birth defects, and neurological problems among the local population.
The response to the disaster spawned the Minamata Convention on Mercury (MCM) in 2013, which aims to protect human life and the environment from mercury pollution. Ratified by 128 countries, including Brazil in August 2018, the treaty regulates the production, import and export of mercury, as well as products containing mercury.
“It’s time to turn off the mercury tap,” Lee Bell, mercury policy adviser at the International Polluters Elimination Network (IPEN), said in a press release following the publication of Orellana’s report. IPEN is a global network of more than 500 NGOs dedicated to eliminating toxins and pollutants from the environment. It served as a major source of information for Orellana’s report linking mercury, small-scale gold mining and human rights.
“There is no legitimate reason to mine mercury and sell it on the global marketplace,” Bell said. “We know that nearly all of it is being directed to small-scale gold mining and deposited directly into the environment, contaminating waterways, fisheries and poisoning communities. We must immediately stop the international mercury trade to end the human rights abuses from small-scale gold mining.”
While the MCM has largely been hailed as a step in the right direction, the convention has a number of loopholes, experts say. Certain countries requested an exemption on the use of mercury in such products as batteries, lamps, cosmetics, thermometers, and dental fillings, which use mercury amalgam.
Contamination in Bolivia
While the European Union and the US have banned mercury exports, numerous other countries continue to profit from the trade. In South America, Bolivia is the leading importer of mercury.
According to the Bolivian Center for Documentation and Information (CEDIB), up to 200 metric tons were imported into Bolivia in recent years. Most of it is used in small-scale gold mining, not only in Bolivia, but also in neighboring countries.
“With the high price of gold and availability of new technology, small-scale gold mining is running out of control,” Carmen Capriles, a founding member of Reacción Climática, an NGO that aims to raise awareness of climate change and environmental degradation, told Mongabay by phone from La Paz. “More and more gold is won, and it is the Indigenous people who bear the consequences. My fear is that it is not this generation but the next that will be worst off.”
From 2019 to 2021, Reacción Climática contributed to the study “Gender, Chemicals and Waste,” which includes a chapter on the use of mercury by artisanal gold miners working in Bolivia’s Beni River.
Capriles and her team took 65 hair samples from Indigenous women in the Eyiyo Quibo and Portachuelo communities, and found mercury levels of 3 to 32 parts per million (PPM). The maximum safe level set by the World Health Organization is 1 ppm, while the recommended level is a maximum of 0.58 ppm.
“Contaminated mothers will pass the mercury to their unborn babies through the placenta,” Capriles said. “There is a grave danger that future babies will be born with neurological problems or birth defects.”
Mercury in Indigenous Brazilians
There hasn’t been a full-scale study into mercury use and contamination in Brazil. Sporadic surveys, however, point to an increasingly dangerous situation, especially since the administration of President Jair Bolsonaro has adopted a hands-off approach to small-scale gold mining.
In 2019, the Indigenous Research and Training Institute (Iepé) participated in a survey in Amapá state, taking fish samples from various locations across the Amazonian state. It found mercury in all 428 samples, 28.7% of them in excess of 1 ppm.
In 2021, Iepé took 34 hair samples from women in the municipality of Vila Nova in Amapá, and found 68% had mercury levels above the WHO’s safe limit.
“We just completed a study of fish markets in 18 cities across the Amazon,” Decio Yokota, the Iepé media coordinator, told Mongabay in a video interview. “We are still analyzing the data, but our preliminary results confirm the trend of high mercury levels in fish.”
In 2020, the Oswaldo Cruz Foundation (Fiocruz), a federal research institution for biological sciences, partnered with WWF Brasil to test samples from Indigenous Munduruku communities in the Amazonian state of Pará. They found that 60% of the participants had mercury levels above the WHO limit. All 88 fish samples taken as part of that study were also contaminated with mercury.
According to the Orellana report, a similar study among the Indigenous Yanomami of Roraima state, who have been deeply affected by small-scale gold mining in their territory, was blocked by Brazil’s Indigenous affairs agency, Funai. Under Bolsonaro, the agency has adopted several measures deemed against the interests of the country’s Indigenous peoples.
Bolsonaro also issued a presidential decree in April 2019, just a few months after taking office, in which he abolished the National Commission for Chemical Safety (CONASQ), among hundreds of other multi-stakeholder councils. Created in 2000, CONASQ was tasked with improving the management of chemical substances in the country, including implementing the Minamata Convention. It consisted of 22 representatives from the public, private and non-governmental sectors.
Experts say the legitimate use of mercury for dental applications is often exploited to distribute mercury for artisanal gold mining. In February 2018, IBAMA, the federal environmental protection agency, seized 430 kilograms (950 pounds) of mercury at Quimidrol, a chemical company in the southern state of Santa Catarina. Having sold 6.8 metric tons of the chemicals in the three previous years, Quimidrol was Brazil’s largest importer of mercury, according to IBAMA. Officially, the mercury was labeled as being for dental use. But IBAMA found Quimidroit had used a shell company in the Amazonian state of Mato Grosso to distribute the metal to gold miners in the region. The address used by the shell company turned out to be the location of a grocery store.
Iepé and Fiocruz contributed information for Orellana’s report, with Fiocruz also drafting a set of recommendations to address rising rates of mercury pollution. These include regular testing of hair samples from at-risk communities, mandatory notification of chronic contamination, establishing a protocol for primary care and a risk management plan for affected communities, and ample monitoring of mercury contamination in fish.
A ‘national challenge’
On Oct. 10, the Brazilian Society of Sciences (ABC) published the report “Contaminated by Mercury: Why do we need an action plan?” The report notes that while Brazil’s Constitution prohibits mining on Indigenous lands, there has been “a systematic invasion of garimpeiros” in recent years “without the state fulfilling its role” of upholding the Constitution.
The result has been the deaths of Indigenous people and environmental destruction, as well as the widespread contamination of ecosystems with mercury, the report says.
It also calls for an updated mercury inventory, given that the last one was carried out in 2016, before the Bolsonaro presidency, and was published in 2019. That inventory estimated the amount of mercury emissions ranging from 69 to 913 metric tons.
Preliminary studies presented at the CONASQ working group on mercury in 2018 estimated that up to 221 metric tons of mercury were used in small-scale gold mining in Brazil.
With the explosion in small-scale gold mining under Bolsonaro, mercury emissions today are likely to be much higher.
The ABC calls mercury contamination a “national challenge” that demands mobilization at all government levels, the private sector, and social and research organizations to implement some of the recommendations listed in its report.
They include resuming Brazil’s active participation in the Minamata Convention, updating the mercury emissions inventory, replacing products and processes that rely on mercury with alternatives, and, last but not least, instituting a “ban on all illegal mining.”
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Mercury rising: Why Bolivia remains South America’s hub for the toxic trade