The relationship between people and the environment is important for human health yet we currently have little understanding of whether and how national development policy might have negative effects on human health through altering the local ecology. This paper takes the example of a policy change in the Philippines that improved the investment climate in the country’s mining sector, to assess the impact gold mining has on cases of malaria through altering the reproductive environment of mosquitoes.

In comparing provinces with and without gold deposits before and after the mining reform, the author finds that afterwards, provinces with deposits of gold had 32 per cent more malaria cases than provinces without gold deposits. Additionally, the impact on malaria appears to be persistent 10 years after implementation of the policy. The author suggests that the main mechanism is through gold mining’s creation of slow-moving bodies of stagnant water, which provide an ideal breeding site for the Anopheles mosquito, malaria’s main transmission vector.

Key points for decision-makers

  • In January 2004, the government of the Philippines launched the Minerals Action Plan (MAP) with the goal of revitalising the mining sector. The Plan streamlined the application process for mining permits, increased the number of issued permits and made it more difficult to hold up operations through legal challenges.
  • This study estimates how this shift in national policy towards a more extractive resource position in the mining sector led to an unintended ecological response regarding an increase in the incidence of malaria.
  • Gold mining sites are typically located within or close to water surfaces, where mines are dug and filled with water. If the gold mines are not properly filled back in, slow-moving bodies of stagnant water provide the ideal breeding environment for the Anopheles mosquito, which carries the malaria disease, to propagate and reproduce.
  • The author examines other possible mechanisms for the increase in malaria, such as migration and deforestation, and finds that neither can explain the increase, further suggesting that the cause is the increase in gold mining’s creation of slow-moving bodies of stagnant water. Monitoring compliance with proper mining protocols or rules may limit the stagnant water conditions needed for malaria to propagate and persist.
  • The author concludes that public policy needs to do more through regulatory or other tools to minimise unintended health effects in the context of mining expansion.
Keep in touch with the Grantham Research Institute at LSE
Sign up to our newsletters and get the latest analysis, research, commentary and details of upcoming events.