Philippines (Mt. Diwalwal) – Cyanide in Artisanal Gold Mining Mercury

the details…
Key pollutant
Mercury, Cyanide
Small-scale gold mining
  • Direct contact
  • Water
  • Soil
  • Air
Population affected
Children Under 6 Affected
Date started
Date completed

Mt. Diwalwal is located in the Southeastern region of the Philippines. In 1982, the discovery of gold on this mountain triggered a gold rush. An estimated $1.8 billion worth of gold reserves remain untapped in the 5,000-hectare mountain where some 30,000 small-scale miners operate, many illegally. The Naboc and Agusan rivers are grossly contaminated with mercury and cyanide from mining operations. Blacksmith is working with local NGOs and government officials to prepare a program to address some of the worst problems.

Health Impact

An op-ed item in September 2001 mentioned a research finding saying that 86% of the miners in Diwalwal were contaminated with mercury. A study conducted by the University of Philippines and the Philippine General Hospital found 36% of the residents of Diwalwal had dangerous levels of mercury in their bodies. Another study by the Department of Health, National Poison Control Information Service and Department of Health, Environment and Occupational Health found that mercury exposure from artisanal gold mining had resulted in blood mercury levels in workers exceeding WHO standards. Health effects included poor memory, anosmia, abnormal gait and balance.