Hair Mercury Levels of Pocket Mining Communities in CAR  

Hair Mercury Levels of Pocket Mining Communities in CAR       

Proponent: Dr. Gaudelia Reyes

While mining is of economic significance to the miners of Northern Luzon, Philippines, it poses health risks due to practices and chemicals employed in the mineral extraction process.  The research aimed to determine the level of mercury in the hair of miner participants.   Three municipalities were identified as study sites.  The variables used are sex, age, income, life style, exposure routes such as diet, years of working as a miner and type of mining job performed. Protective gears used during mining activities were also identified.  Hair samples were collected following standard procedures and were analysed for mercury content.


Findings show that:

  • There are more male than female small scale miners in the study sites however females and their children are also involved.

  • Different age groups are engaged in mining activities including children and elderly but majority are relatively young. The incomes are varied depending on whether they operatetheir own small mine or they are employed by operators.

  • There are fewer smokers than non smokers but more alcohol consumers than non drinkers.

  • Fish and meat are part of the diet of the miners but are not consumed daily.

  • Majority have worked as miners for less than five years. They performed different mining activities and none of them is limited to one mining activity. One of the activities performed by a smaller group is mercury amalgamation.

  • The miners performed different mining activities which include mercury amalgamation, among others.

  • As regard to the hair mercury content, only 8 out of the 246 (3%) participants have mercury levels higher than the maximum limit set by EPA.

  • No correlation was established between hair mercury level of participants and income, age, fish and meat consumption and number of years working as a miner.

  • Mining activities such as panning, sluicing, skimming, and mercury amalgamation resulted to higher mean mercury levels in the hair of the miners.

  • All study participants used helmets. The use of other protective gears such as boots, masks and goggles was not complete and compliance was low. Miners who used PPE generally had higher mercury levels than those who didn’t. The gears are not properly monitored and cleaned as required.

  • In conclusion, small scale mining in the three representative communities continue to be a source of livelihood and may include male, female members and children. The hair mercury levels of the small scale miners who participated in the study are within safety limits set by EPA with the exception of a few (3%). Mercury amalgamation is still used by small scale miners in the communities under study although they comprise a small part of the population (25%). The only variable that had a significant effect on the hair mercury level is the type of mining job performed.


  1. Since the material used for laboratory analysis in the study is human scalp hair, a similar study may be conducted using other specimens such as blood and urine.
  2. Cyanide is used by the miners in the three mining communities for mineral extraction. The level of cyanide in the human body and their symptoms among the miners may provide a basis for assessing the toxicity of cyanide among them.
  3. Improper use of PPE can be a contributory factor to an increased mercury level in the body. A study on practices of small scale miners on the use of PPE can be considered.
  4. A similar study can be done in mining communities where fish consumption is high. In this study, fish consumption was low among the participant small scale miners.

This project was funded by the Department of Science and Technology – Philippine Council for Health Research and Development (PCHRD), thru the Cordillera Regional Health Research and Development Consortium (CRHRDC) under the Regional Research Fund mechanism.

The results of the study may serve as a basis for Program Policy Recommendations to the mining communities.