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Ending the toxic trail of small-scale gold mining


Strapped together by tape and frayed ropes, wooden logs demarcate the mineshaft’s entrance, a hole in the ground no larger than a metre square.

A young man nearby cranks a lever, kickstarting some generators. The steady hum of the machinery blends with the creaking of a pulley system, drowning out the sounds of the gentle breeze blowing through the mining site, located in Paracale, north Philippines.

A young man tied to a harness begins his descent down the pit and deep beneath the planet’s surface, his headlamp the only visible source of light. Upon reaching the bottom of the cramped mineshaft, he pulls out a small chisel and hammer and begins chipping away at the rock.

When he returns to the surface, he deposits a sack of ores into a barrel. Another miner mixes the ores with water before adding drops of mercury, which binds to any gold particles to create amalgams. These are then heated to evaporate the mercury, leaving behind gold.

While it is fast, this process comes at a cost for these miners, their families and their future generations.

Mercury is a toxic chemical that can cause irreversible brain damage and disrupt ecosystem health. There is no known safe exposure level for elemental mercury in humans, and effects can occur at even very low levels.

An artisanal miner ascends from a mineshaft in the Philippines.

Globally, up to 20 million miners work in artisanal and small-scale gold mining operations, which experts say are often unregulated and unsafe. Photo credit: UNEP/Veejay Villafranca

“Gold mining is a big part of our life. We don’t like using mercury but we have no choice,” says Demver Suzara, president of the mining association overseeing the site. “It’s dangerous. Mercury should be banned.”

Globally, up to 20 million miners in over 80 countries work in artisanal and small-scale gold mining, including 4–5 million women and children. These operations, which are often unregulated and unsafe,  are responsible for 37 per cent of global mercury pollution – more than any other sector.

The planetGOLD programme, led by the United Nations Environment Programme (UNEP), aims to end the toxic trail of small-scale gold mining. Representatives work with governments, the private sector and mining communities across the world to eliminate mercury from artisanal mining and promote safer work environments. Funded by the Global Environment Facility, it operates under the Minamata Convention on Mercury, a global accord designed to phase out the use of mercury.


"Over 100 million people rely on artisanal gold mining for their livelihoods, so it’s critical that we work with governments to equip miners with the knowledge and tools necessary to phase out mercury use"

-- Ludovic Bernaudat, planetGOLD programme manager.

Strengthening governance

Artisanal mining accounts for 20 per cent of the global supply of gold and generates approximately US$30 billion annually.

Yet artisanal operations are informal and fall outside the purview of existing national regulatory frameworks. This can be because governments lack access to reliable information about the sector, are unable to provide administrative, technical and financial support, or favour large-scale mining operations.

“Existing policies and regulations unintentionally create a barrier to formalization due to [their] lengthy, expensive, and too technical requirements and processes,” adds Abigail Ocate, national project manager of planetGOLD Philippines.

Many governments are taking action to implement safer standards under the Minamata Convention on Mercury, which aims to comprehensively regulate the element throughout its life cycle, from production to use to disposal. But enforcement is not always consistent, especially in rural areas and developing nations, giving rise to unsafe artisanal operations.

For example, over 250,000 miners in Kenya – many of whom are young adults that lack other job opportunities – are involved in small-scale gold production, mostly along the Lake Victoria basin in the south-west of the country. However, without formal financial and technical support from governments, they face barriers in obtaining funding for mining equipment.

“I thought it would be simple, but I got it wrong,” says Emmanuel Nyaga, a 21-year-old small-scale miner in Kisumu. “The work is too hard. It would not be my job of choice. But I’ve been here one year.”

Gold miner sifting for ore.

The planetGOLD programme, led by UNEP, works with governments, the private sector and mining communities across the world to eliminate mercury from artisanal mining and promote safer work environments. Photo Credit: UNEP/Duncan Moore

Nyaga, like many working in the sector, only receives payment every two weeks and must find alternative work on most days of the country’s six-month rainy season.

“Since we started mining from our forefathers, we have never been legalized or formalized,” says Kephas Ojuka, chairman of a miners’ association in the region. “We [want] alternatives to mercury so that our lives are never affected again [and to] formalize our activities so we can work legally.”

Mercury combines with gold to create an amalgam.

In a practice that dates back 3,000 years, many small-scale mines add mercury to gold ores to create an amalgam, which is then heated to evaporate the mercury, leaving only gold. Photo Credit: UNEP/Veejay Villafranca

Artisanal and small-scale mining emits over 2,000 tonnes of mercury per year. This includes emissions to air from heating amalgams, as well as direct losses of mercury to land and water. The chemical, which has been used in mining for over 3,000 years, does not degrade in the environment. Research shows that forest canopies near small-scale gold mining sites can intercept and accumulate large volumes of atmospheric mercury pollution.

This means mercury can build up and be passed along the food chain. It can then cause nervous, digestive and immune system damage to animals and humans alike. Estimates suggest that up to 100 million people are directly or indirectly exposed to mercury from small-scale gold mining.

A new gold standard

To counter gold mining’s toxic trail, planetGOLD is facilitating the sharing of technical materials and guidance between artisanal gold mines and governments. It is also advocating for new technological alternatives to reduce and ultimately eliminate reliance on mercury.

The first phase of planetGOLD initiated projects to improve access to finance in nine countries, including Kenya, the Philippines and Indonesia. The project aims to reduce mercury use in small-scale mining by an estimated 369 tonnes and has already equipped thousands of miners with greater understanding of safer mining practices.

PlanetGOLD is set to expand to an additional 15 countries and leverage co-financing of over US$342 million during its second phase in 2023. With this expansion, it aims to reduce mercury use by an additional 143 tonnes, improve over 1.2 million hectares of land, mitigate some 400,000 tonnes of carbon dioxide equivalent emissions and benefit 370,000 people over the next six years.

Selling Gold

A gold dealer in Paracale shows off locally mined gold. Photo Credit: UNEP/Veejay Villafranca

In this second phase, planetGOLD will helping artisanal mines formalize their operations, says Bernaudat.

“The informal status of many mining communities makes it difficult to phase out mercury. So, bringing miners into the formal economy can result in higher incomes and better working conditions, while helping to overcome social and environmental challenges.”

In August 2022, planetGOLD officially opened its latest mercury-free processing plant in Burkina Faso. It is teaching local miners to harvest ore without resorting to mercury.

“The miners were really happy,” says Abel Ouedraogo, a senior exploration geologist at the site. “They told us, ‘We are confident the processing plant will help us transition from mercury use to a mercury-free system. We are very happy."

This article was originally published by UNEP on February 15, 2023.