Successful Senegalese Mercury Mitigation

After four years of work, Blacksmith Institute has broken the cycle of dangerous mercury use by Senegalese gold miners deep in western Africa. Education and simple technology have minimized their exposure to mercury and its release into the environment.

Senegal's Kedougou region was chosen for Blacksmith's pilot project because of its large gold deposits. Almost a quarter of the world's gold supply can be traced to the 10-15 million, poor, small-scale, gold miners scattered around the globe like those in Kedougou. They constitute the third largest source of mercury pollution in the world today.

Miners extract gold-laden rock, grind it into a fine sand, which they mix with mercury to form an amalgam subjected to high heat-either with a blow torch or over an open flame. Mercury evaporates into the atmosphere, leaving behind roughly 80 percent pure gold. Evaporation is the problem.

Gaseous mercury may be inhaled by the workers and their families, leading to serious health issues. It may settle into the surrounding environment, seeping into the ground and contaminating the water supply. It may rise into the atmosphere, where it circulates for about three months before raining down again, dispersing more or less evenly around the earth. In the process elemental mercury is transformed into methylmercury-one of the most toxic organic substances that works its way up the food chain...everywhere.

However, using retorts during the mercury burn-off stage is a very simple and highly cost-effective way to control this injurious mercury release into the environment. Retorts efficiently capture and reuse mercury, minimizing occupational exposure and environmental dangers. Consequently, Blacksmith's project goals were to sensitive workers and their families to both the health and environmental harm of unchecked mercury evaporation, and to popularize the beneficial use of retorts.


It was challenging. Access to the mining communities was difficult because of their rural location and the poorly developed national infrastructure. Blacksmith invested in motorbikes and maintenance equipment to overcome the problem. Gaining the miners' trust in order to teach the dangers of mercury contamination proved to be more difficult and time consuming than expected. Further, some minors refused to use certain types of retorts because they slowed the mercury evaporation process.

However, meetings were successfully organized about the use and importance of retorts, followed by informational sessions with coordinators from a local technical college who showed miners their use. These coordinators and their supervisors then monitored the retort process and encouraged progress. In total, nine meetings took place over three months, designed to reach nearly 4,000 people, in 11 villages, in addition to 23 follow-up visits.

While rates varied widely, progress was made across the board over the entire project area. The number of total retorts increased by over 400 percent. Where no retorts previously existed, their introduction was an unmitigated success. Where retort use had previously been introduced, the progress rate remained satisfactorily regular. The originality of the project, including the participation of coordinators, raised the introduction of retorts in small-scale gold mining to a leading national issue in Senegal. In summary, the Blacksmith project has been hugely successful in meeting its goals.

Blacksmith's implementing partners for the project were the Senegal Ministry of the Environment, AfricaClean, and the US Environmental Protection Agency. Other partners were PASMI-Programme d'Appui au Secteur Minier and l'ONG "La Lumiere."


Support from donors and potential stakeholders is needed to meet the demand for larger quantities and sizes of retorts. The regulation of their sale and stockpiling as well as the usage of mercury must be implemented. To encourage more progress, further improvements remain to be made, including-

* acquiring better retorts;
* monitoring local mercury levels;
* continuing education and popularization of retort benefits;
* minimizing direct exposure by equipping miners with gloves and masks;
* continuing partnerships with local authorities, media, and others;
* creating a health panel on the alert for the first signs of continuing high levels of contamination;
* creating a system that formalizes and controls mercury circulation.