HEAVY METAL ANALYSIS OF OREGANO (Coleus aromaticus Benth) USING MICROPLASMA-ATOMIC EMISSION SPECTROSCOPY

To determine if oregano plant can accumulate heavy metals like Cu, Cd, Ni, Pb and Zn and assess the relative safety or potential health risks oregano from the selected areas in Nueva Ecija and Occidental Mindoro based on the World Health Organization (WHO) standard limits, oregano leaves were collected in five sampling sites in Nueva Ecija and Occidental Mindoro. Multi element analysis was carried out on the oregano plant materials through Microplasma-Atomic Emission Spectroscopic (MP-AES) technique. MP-AES is a powerful and quick multielement analytical tool with high sensitivity. Digestion of the plant materials were done prior to heavy metal analysis. Content of metal per sample was expressed as µg/g. Heavy metals (Cu, Cd, Ni, Pb and Zn) which are potentially toxic elements were present in the oregano leaves samples. All the oregano leaves samples exceeded the WHO permissible limits of heavy metals in medicinal plants.