Breaking Mercury’s Stubborn Hold on Gold

When Alfonso Rodriguez talks with gold miners in Peru or Colombia about the health hazards of mercury, which is commonly used in small-scale mining operations to separate gold from mined rock, he often hears a familiar response. 

“Their first statement is, ‘I know mercury is bad for me and bad for my family, but I need the money to survive,’” says Rodriguez, the technical director for Pure Earth, a nonprofit organization that works to reduce the use of toxic chemicals in mining across 10 countries. “They may give up mercury for two or three weeks, but then they are back using it again.”

Such anecdotes illustrate the difficulty of eliminating mercury in artisanal and small-scale gold mining, sometimes called ASGM, the largest source of human-caused mercury contamination on the planet. Since 2017, when 128 countries agreed to reduce mercury pollution at the landmark Minamata Convention, governments and development agencies have tried various ways  to curb use of the neurotoxin, which is linked to a host of health and environmental problems. But the practice remains widespread, accounting for nearly 40 percent of all the mercury released into the environment, according to estimates. 

“We know the problem is there,” says Rodriguez, who has been working to address mercury contamination in mining for the past eight years. “The question is how do we solve it.”

Building a Community of Evidence

Duke professors William Pan, Dr.PH., and Alex Pfaff, Ph.D., share Rodriguez’s frustration with the slow pace of change in gold mining. But they hope to jumpstart progress with one thing they say has been lacking in the efforts thus far to accelerate a transition to mercury-free mining: evidence. 

“Technologies and methods are used in ASGM that have limited or no scientific evidence to show whether they will be adopted by miners,” says Pan, the Elizabeth Brooks Reid and Whitelaw Reid Professor of Global Environmental Health at Duke. “They are often tried without evaluations of what generated desired impacts versus what didn’t.”

This past fall, Pan collaborated with Pfaff, a professor of public policy and economics, to organize a series of webinars to collect, share and ideally inspire more evidence about the various strategies to reduce mercury contamination in mining, covering everything from the development of mercury-free mining technologies efforts to foster a premium retail market for mercury-free gold. Rodriguez was among more than 100 people who participated in the discussions, which included representatives from gold mining operations, government agencies, nonprofit groups and the jewelry industry. 

The goal, the professors say, is to create an ongoing dialogue among policymakers and funders about what strategies are actually generating desired outcomes – both in terms of reducing the harms from mercury, which washes from mining sites into the surrounding ecosystem, contaminating food and water that local populations depend on, and improving miners’ financial incentives to adopt safer practices. They say the mindset needs to evolve away from investing money in ideas that may sound good in concept, but have no real track record of success.

“When a lot of resources are spent on policy interventions, an important role for the academic sector is to organize the facts about what worked well and what didn’t work,” says Pfaff, who studies the economic and environmental impact of policy implementation. “We’d like to see fewer resources going toward things that have been shown not to be very effective.”

'Hopeful Interventions'

The efforts to eliminate mercury pollution are complicated by the informal nature of artisanal and small-scale gold mining, which is practiced in more than 80 countries and accounts for about 20 percent of global gold production. While some countries have banned mercury use in mining, regulations and legal enforcement can vary significantly across borders, leaving plenty of room for miners to operate on the periphery of the law. Small-scale miners also typically lack the capital or expertise to invest in newer, mercury-free mining technologies.

At the same time, mining provides a way of life for an estimated 20 million people, most of whom live in remote areas with few other economic opportunities. “If they could make the same money doing something else, they would,” Rodriguez notes.  

Despite those obstacles, some governments and other groups have launched “hopeful interventions” that have the potential to reduce mercury use in the industry, says Susan Keane, the global coordinator of Planet Gold, an initiative led by the United Nations Environment Programme to aid countries in meeting the targets of the Minamata Convention. But very few of those projects have collected or shared data that demonstrate they are effective – or how they might be translated to other settings, she says.

”If we’re going to make any progress in reducing mercury use in this sector, we have to share experience on what works and what doesn’t – what interventions  are resulting in actual reductions and under what circumstances,” says Keane, who participated in the webinars. “Having an evidence base is critical to accelerating progress in this sector.”

Pan and Pfaff hope the webinars become a starting point for building that evidence base. The Duke team is amassing a database of all available research on the impacts of mercury use and strategies to reduce it, which they plan to annotate and share with everyone who participated in the online discussions. 

They are also exploring a partnership with the Inter-American Institute for Global Change Research (IAI), an intergovernmental organization involving 19 countries across the Americas that works to build capacity and share best practices to address issues such as climate change and environmental policy. 

“We hope this kicks off some complementary efforts to keep building more evidence of what works,” Pfaff says. He and Pan note that governments and agencies also can advance a culture of more rigorous evaluation by demanding a higher bar of proof when they fund projects, as well as data collection and follow-up research on initiatives that are deployed in the field.

Putting a Focus on Hellth

For Pan, who has been studying the environmental impact of gold mining in Peru and other Latin American countries since 2011, there is another potential benefit to engaging with the many players working toward cleaner gold. While he agrees with the goals of the Minamata Convention to reduce mercury use at mining sites, he worries it creates too narrow a focus on that measure alone as a barometer of success. What’s missing in that picture, he says, are the spillover health impacts of mercury that is already in the environment. 

“Even if you stopped using mercury in mining today, mercury stays in the environment and keeps circulating,” he says. “In addition, other health problems related to ASGM, such as malaria, tuberculosis and HIV, would continue. So we need to understand what the full impacts of these interventions are on human health.”

To that end, Pan sees the webinars, along with the Duke team’s plans for continued engagement with stakeholders, as a platform for prioritizing those unmet research needs, which he says are critical to understanding the full costs to human and environmental health of gold mining’s continued reliance on mercury.

Rodriguez, for one, would love to see a deeper exploration of those issues, because it’s what he’s often asked about when he visits communities around gold mining sites. “If I can show them that a change in the food they eat or the crops they grow or even how they wash their clothes could improve their health,” he says. “I think that is information that they will be very interested in having.”