The identification of indigenous Cu and As metallophytes in the Lepanto Cu-Au Mine, Luzon, Philippines

  • Rene Juna R. ClaveriaEmail author
  • Teresita R. Perez
  • Rubee Ellaine C. Perez
  • John Leo C. Algo
  • Patricia Q. Robles


The mining activities in the Lepanto Cu-Au Mine which is situated within the Mankayan Mineral District in the Philippines have exposed the arsenic (As)-rich copper (Cu)-gold (Au) and polymetallic ores to surface conditions. Cu and As dispersal into nearby soils and waters could pose health hazards to the natural ecosystems and human settlements. The study focused on the identification of indigenous metallophytes thriving in the area as well as the bioavailability of Cu and As in soils and its implication to the growth of the indigenous plants. Particular interests were on plant species that are capable of Cu and As absorption and have potential applications to mine rehabilitation. The samples were analyzed for total Cu and As contents. The soil samples were also subjected to different physicochemical analyses such as pH, organic matter, and nutrient content. Fern species had relatively high Cu and As contents in their biomass than other plant species found in the study area. The Cu and As concentrations in the plants might have been strongly influenced by the bioavailability of the metal and metalloid which were dependent on the physicochemical properties of the soil such as pH, organic matter, and nutrient contents. These identified metallophytes namely Dicranopteris linearis, Histiopteris incisa, Pityrogramma calomelanos, Pteris vittata, Nephrolepis hirsutula, Pteris sp., Pinus sp., Thysanolaena latifolia, and Melastoma malabathricum have tolerated the different Cu and As concentrations in the soil thus could be useful and effective for ecological restoration as an option to post-mining rehabilitation.


Bioavailability Rehabilitation Phytoremediation Hyperaccumulators 



This research project was supported by the Philippine Council for Industry, Energy and Emerging Technology Research and Development (PCIEERD) under the Department of Science and Technology. The authors would like to acknowledge the logistical support provided by the Lepanto Consolidated Mining Company and access to the abandoned Japanese Tunnel. Appreciation is also extended to the following analytical laboratories: Philippine Institute of Pure and Applied Chemistry (PIPAC), First Analytical Services and Technical Cooperative (FAST), Ostrea Mineral Laboratories Inc., and Natural Sciences Research Institute (NSRI) for providing the chemical analyses of the different soil and plant samples. Our sincerest gratitude is extended to the 3 reviewers of this paper where comments and suggestions have greatly improved the content and presentation of data as well as discussions of interpretations and implications. To them we are most grateful.


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Authors and Affiliations

  1. 1.Department of Environmental ScienceAteneo de Manila UniversityQuezon CityPhilippines

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