Zimbabwe pushes mercury-free gold mining

AT Museveni Mine in Bindura, 32-year-old artisanal miner Mavies Gwiriko carefully swirls crushed gold ore with mercury under the harsh sun, unaware that the toxic substance she handles daily can cause severe damage to the brain, kidneys, lungs and nervous system.

With no gloves or protective equipment, she repeatedly mixes muddy ore with mercury — a widely used metal in artisanal and small-scale gold mining — as part of the amalgamation process used to extract gold.

Beside her sits a small green bottle of mercury, which she frequently reaches for, despite the absence of any protective measures.

"I started mining two years ago," said Gwiriko. "We process gold using mercury because it easily captures the gold. To be honest, this is the first time I am hearing that there are health hazards associated with mercury."

Her experience reflects the reality of thousands of artisanal and small-scale gold miners across Zimbabwe, where mercury remains a central tool in gold extraction despite its well-documented health and environmental risks.

Artisanal and small-scale gold mining has become a significant livelihood activity in Zimbabwe, employing an estimated 300 000 people. The sector is concentrated in provinces including Midlands, Mashonaland West, Matabeleland South and Mashonaland Central, which host tens of thousands of miners operating at hundreds of processing sites.

However, experts estimate that about 96 percent of artisanal mining sites still rely on mercury, releasing more than 24 tonnes of the toxic metal into the environment annually. The sector now accounts for more than 40 percent of Zimbabwe's mineral exports.

Health specialists warn that mercury exposure can lead to neurological damage, tremors, memory loss, developmental disorders in children, reproductive complications and organ failure. Environmental experts also caution that mercury persists in ecosystems for decades, contaminating rivers, soils and the food chain.

The planetGOLD Zimbabwe project, supported by the Global Environment Facility and the United Nations Environment Programme and implemented in collaboration with government ministries and the Environmental Management Agency, is working to reduce mercury use through awareness campaigns and alternative technologies.

Project manager Nyaradzo Mutonhori said efforts are underway to introduce mercury-free gold processing systems at demonstration sites across the country.

"We are going to be introducing mercury-free gold processing technologies at eight demonstration sites in Zimbabwe," she said. "The aim is to reduce the use of mercury by 4.85 tonnes."

The project is currently active in 11 districts and focuses on formalising artisanal miners, improving access to finance, introducing safer technologies and raising awareness about mercury risks.

Engineers and metallurgical experts involved in the programme say alternative methods already exist, including gravity concentration, direct smelting, leaching and cyanidation techniques that eliminate the need for mercury.

Engineer Molline Siwela said ore samples from different mining sites are being analysed to determine the most suitable mercury-free technologies for specific geological conditions.

Officials from the Ministry of Mines and Mining Development say these alternatives could significantly reduce environmental damage while improving efficiency in gold recovery.

Despite these efforts, uptake remains slow due to limited awareness, lack of equipment and financial constraints facing small-scale miners.

For miners like Gwiriko, the shift away from mercury may take time. As she continues her work at the processing site, the green bottle of mercury remains within reach — a symbol of both economic survival and an invisible public health risk that experts warn can no longer be ignored.