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The Dirty Secrets of Gold Mining in Senegal

“Look at it,” Samba says as he hands me a solid piece of gold. “It’s better than farming.” I take the gold nugget in my hand. It shines in the late morning sun, beautiful despite its ugly history. The past few months of digging for gold as an artisanal gold miner have paid off for...

Photo by Jacqueline Gerson.

“Look at it,” Samba says as he hands me a solid piece of gold. “It’s better than farming.”

I take the gold nugget in my hand. It shines in the late morning sun, beautiful despite its ugly history. The past few months of digging for gold as an artisanal gold miner have paid off for Samba — he now has enough money to feed his family for the rest of the year.

Artisanal gold mining (AGM) in Senegal has dotted the landscape since the 1990s, but has increased dramatically over the past decade. Men and boys from throughout southeastern Senegal, as well as nearby Mali, Guinea and Benin, flock to the region of Kedougou to engage in the backbreaking labor of AGM. All are motivated by the hope of finding a large nugget so that they can feed their families, pay school fees, buy new clothes and maybe even afford to move from their rural farm villages to a house in the city.

senegal, africa, mining, gold
Photo by Jacqueline Gerson.

Despite the lure of striking it rich from AGM, it is a process wrought with danger, particularly because of the mercury used in the process. Miners like Samba work in teams to dig for gold. They remove hundreds of pounds of soil each day, carrying it from the mines in rice sacks to their shantytown homes a few kilometers away. Mondays and Fridays are reserved for sorting through this soil to extract any gold — it is believed that these days belong to the genies (evil spirits), so no one can work in the mines without being fatally injured. It is during this processing phase that mercury enters the picture.

I watch as Samba’s team pours water into a large bucket filled with mined dirt. This is then passed down a wooden riffle — a board propped at a 45-degree angle — and covered with a coarse cloth. The copious amounts of water added afterward push the lighter dirt and minerals into a small holding pond at the base of the riffle. Heavier gold particles stick to the cloth and are thereby separated from the soil. After nearly 100 pounds of soil have been passed through, Samba removes the cloth and dunks it several times in a bucket of water, massaging the cloth to remove all the gold particles. He then pulls a small plastic bag of mercury out of his pocket, pours a few grams of the liquid metal into the bucket and proceeds to mix it into the brown solution with his hands.

Five minutes later, he holds out his bare palm for me to see a small silver-colored ball. “It is gold covered in mercury,” he explains. The mercury is particularly attracted to the gold. Thus, as he mixes it into the soil-water solution, mercury seeks out the gold particles and forms a layer around them. This dense mercury-gold amalgam then falls to the bottom of the bucket, where Samba can easily retrieve it.

Once these mercury-gold amalgams have been collected in a small tube, the next step is to bring them to the home of a gold buyer. We traipse through the shantytown to the home of Samba’s gold buyer, Mussa. His hut looks just like all the others — walls constructed from woven dried reeds, roofs made from rice sacks sewn together and precariously balancing on the walls, and a dirt floor. He leads us into his bedroom and points to a bench for us to sit on. Then he puts his hand out for the amalgam.

senegal, africa, mining, gold
Photo by Jacqueline Gerson.

Samba pours the mercury from the tube into Mussa’s hand. Mussa examines it carefully, then places it on a small metal dish, which he lights. I leave the room at this point, afraid to breathe in the toxic mercury vapors, but Samba and Mussa remain. They soon call me back into the room and point to the solid gold sitting where the amalgam was minutes before. Samba smiles as Mussa pays him for the gold, carefully counting aloud as he is handed each bill.

But Samba’s net profits are much less than they seem from a quick glance at this exchange and the bulge in his pocket. Not only are the profits divided among his team, used to pay for mining supplies (shovels, a water sump pump, etc.) and given to the women who cook meals for them (women seldom follow their husbands or sons to these transient communities), but they must also be used to pay for the inevitable health impacts associated with mercury usage.

Mercury is a potent neurotoxin that can cause debilitating health effects in those exposed to it. Think of the Mad Hatter from Alice in Wonderland; the mercury used to line felt hats entered his body, passing the blood-brain barrier and leading to his crazed state. At low doses, mercury exposure can lead to tremors, loss of coordination and skin rashes. But as mercury accumulates in the body over time, it can lead to memory loss, impaired speech and even death. Mercury can also enter fetuses in pregnant women, leading to birth defects and impaired childhood development.

People are primarily exposed to mercury when consuming large fish such as tuna. In AGM villages, mercury can also be inhaled directly from the air. In fact, mercury levels in gold buyers’ huts can reach levels up to 1,000 times that recommended by World Health Organization (WHO) standards. The mercury in the air can be transported for hundreds of thousands of miles, falling as rain or with dust particles in areas as far away as France and the United States. AGM is the number one source of mercury globally, contributing more to mercury contamination than coal combustion. Yet, while much of the mercury used in AGM travels far from its source, most of it remains in the local area, polluting the community’s air, water and soil. There are alternative AGM methods that either eliminate mercury use or reduce its loss to the environment, but these are not commonly practiced.

senegal, africa, mining, gold
Photo by Jacqueline Gerson.

I walk back with Samba, listening as he plans the good meals his family will be able to eat as a result of the gold he sold today. As he talks, I get lost in his dreams and for a brief moment I understand why he risks so much to be a part of the AGM community.

We part ways at the road. He returns to his transient hut, where he’ll relax for a few hours in preparation for another long day at the mines tomorrow. I catch a shared taxi for the two-and-a-half-hour ride back to the regional capital. As I sit squashed in the backseat, I watch as we pass mining village after mining village — each with its own people and experiences, but with stories that parallel those of Samba and his team. In Kedougou, Senegal, the search for gold and the dangers of mercury are part of the story of thousands of people.

Read more of Jacqueline Gerson’s work at!

Jacqueline Gerson is a PhD student in ecology at Duke University and director of Girls on outdoor Adventure for Leadership and Science (GALS). Her research examines the impact of human activities on water quality and human health. She is also passionate about youth environmental education through place-based learning. When she is not collecting samples and analyzing them in the laboratory, she can be found hiking, kayaking, camping or exploring the outdoors in another fashion. 

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