Blood Mercury Level of Employees from Selected Small-Scale Mining Industries in Maco, Comval Province

Annabelle A Ribo, Dency Mae V. Racacho V Racacho, Gilroy S Rosalinda, Jhuana Mae S Libumfacil, Vanessa Jan O Barrete


Gold mining is economically significant yet it poses various harmful effects like mercury poisoning. The study determined the mercury level in blood samples taken from employees of selected small-scale mining industries in Barangay Limbo, Maco Comval Province. Specifically, it documented the profile of the miners in terms of age, length of employment, job description, and their corresponding blood mercury level and how this compares with the tolerable limit of mercury in the blood set by the DOH. Blood samples were collected by venipuncture and tested using Cold Vapor-Atomic Absorption Spectrophotometer. The findings of the study show that in terms of age; 6 miners were within the age of 16-30 years old, 3 miners were 31-47 years old, 2 were 48-62 years old, and 2 were 63-77 years old with mean mercury levels of 0.390 ppm, 0.097 ppm, 0.199 ppm, 0.149 ppm respectively. For the years of employment; 4 miners were active for <1 year while 8 miners were active for 2-3 year and only 1 miner was active for >3 years with mean mercury levels of 0.099ppm, 0.341ppm, 0.197ppm respectively. In terms of job description, 6 were involved in crushing of ore in ballmill, 5 were involved in addition of mercury, and 2 were involved in recovering gold by torching with mean mercury levels of 0.398ppm, 0.073ppm, and 0.158ppm respectively. All these blood mercury levels exceed the tolerable limit of 0.015 ppm set by DOH. nonetheless, there was no significant difference in the level of mercury in the subjects’ blood samples in terms of age, length of employment and job description. That the blood mercury levels of the subject all fell over the tolerable limit is alarming since the small scale mining industries included in the study mostly have young miners as emplyees.

Full Text:



Alicia E. et al. (September 12, 2011). A method for the measurement of mercury in human whole blood. American Journal of Analytical Chemistry, 2, 752-756

Dept. of Environment and Natural Resources. (2008). Retrieved January 02, 2012, from,

Asirot, J.P., & Israel, D.C. (2002). Mercury pollution due to small-scale gold mining in the Philippines: an economic analysis. Retrieved December 08, 2011, from

Bishop, M.L. (2010). Clinical Chemistry: principles, procedures, correlations. Philippine Edition. Lippincott Williams & Wilkins.

Bose-O’Reilly, S., et al. (2002). The Mt. Diwata study in the Philippines 2000 treatment of mercury intoxicated inhabitants of a gold mining area with DMPS. Retrieved January 06, 2011, from http:Upload/Philippines%202003%20O’Reilly%20chelating%20agents.pdf

Caldwell, J. (2012). Risk Assessment in Mining. Retrieved January 8, 2012, from

Carter, R. (2005). Mercury Poisoning. Retrieved December 08, 2011, from


  • There are currently no refbacks.