Mercury Contamination from Artisanal Gold Mining – Central Kalimantan, Indonesia

the details…
Key pollutant
Artisanal gold mining
  • Direct exposure
  • Water
  • Airborne
Population affected
Children Under 6 Affected
Artisanal Gold Mining
Date started
February 2009
World Bank, EC/UNIDO, Pure Earth individual donors
Project Partners

The Problem

UNIDO estimates that mercury amalgamation from this kind of gold mining results in the release of an estimated 1,000 tons of mercury per year, which constitutes about 30 percent of the world’s anthropogenic mercury emissions. It is estimated that between 10 and 15 million artisanal and small-scale gold miners worldwide, including 4.5 million women and 600,000 children [1]. According to UNIDO, as much as 95 percent of all mercury used in artisanal gold mining is released into the environment, creating a danger on all fronts—economic, environmental and human health (2005). Covered by the 2008 World’s Worst Polluted Places Report, ASGM still threatens today’s world environment and public health.

Health Impact

Children that are exposed to mercury are particularly at risk for developmental problems. Exposure to mercury can cause kidney problems, arthritis, memory loss, miscarriages, psychotic reactions, respiratory failure, neurological damage and even death.

Exposure Pathways

Mercury is a persistent global contaminant, and it has dangerous effect to the human’s vital organs. Mercury can enter the human body through various pathways, including inhalation, ingestion, skin contact, as well as maternal mercury transfer. Once mercury is released into waterways, it becomes a more toxic form of methyl-mercury, which bioaccumulates in the food chain (e.g. high fat-content fish) through bacterial digestion.

Past Activity

Having identified major sources of mercury emissions, YTS is currently implementing a community-based, participatory project to reduce atmospheric mercury releases. The organization has done so by conducting a program of direct intervention, aimed at lowering the level of mercury consumed by gold-processors and subsequent emissions from burning mercury amalgam. Improving local technologies provides an important entry-point into this community and allows the project to collaborate with the gold-processors to reduce mercury emissions and the demand for mercury.

Moreover, improvements in technology not only provide better economic returns due to efficient recovery; but also create safer surroundings for people to work in. In Mt. Muro, the work focused on designing, manufacturing, transporting, field-testing and distributing efficient and safe large-capacity retorts capable of burning from 10 to 30 kg of amalgam per session. When this retort is used on daily basis, a 20-percent increase in efficiency is expected compared to the current locally made retort used by the miners.

One of the major operators who have tested the 30 kg capacity retort reported a recapture rate of 90 percent (estimated 80 – 100 kg per month) and a corresponding reduction in costs to miners. Additionally, YTS continues to distribute small-capacity Fauzi retorts for burning amalgam balls of less than 1 kg. In the Upper Kahayan River, the intervention activities focus on supplying water-box condensers to gold shops that are burning gold-mercury amalgam.

In the latest efforts, miners in Gunung Mas are taught about the health effects of Mercury and research is being done on alternative methods that would be be mercury-free.


As a result of the use of the retort and water-box condensers YTS distributed in one district, 2,390 kg of Hg (approximately USD 140,000 of value) are now prevented from being released into the environment per year.

Current Activities

YTS, a local NGO with strong connections to the communities and the local authorities, has been working with Pure Earth support to expand health trainings and alternative methods trainings to miners and their families in order to reduce the amount of mercury used and the consequent health impacts.