International Journal of Environmental Engineering
Author(s) : CHANNRATHA PRUM, PAITIP THIRAVETYAN, RUJIRA DOLPHEN
Arsenic (As) contamination in the environment is a worldwide problem. Many technologies such as oxidation, membrane technology, adsorption, electrokinetics, ion exchange have been used to remove As from contaminated water. However, these technologies are required high costs and skillful labor for control and maintenance. Phytoremediation, using plant to remove pollution, is a cost effective and eco-friendly technology. Nevertheless, this technology still brings about limitations such as high phytotoxicity of As. Application of microorganisms to enhance heavy metal removal by plant might be an effective technology. Some plant species such as Echinodorus cordifolius, Cyparus alternifolium, Acrostichum aureum, Coolocasia esculenta, and Echinodorus cordifolius were screened for As removal efficiency. From our screening plants revealed that E. cordifolius was the highest efficiency species for As removal. Combination between E. cordifolius and microorganisms for As removal was studied. Bacillus subtilis and Anthrobacter creatinolyticus (isolated from arsenic contaminated soil from Nakhon Si Thammarat province) were used to compare As removal efficiency. The result showed that at 1st and 2nd cycle of experiment, As removal was no significantly different between non-inoculated E. cordifolius and inoculated E. cordifolius. After that at 3rd and 4th cycle of experiments, E. cordifolius inoculated with A. creatinolyticus had the highest As removal efficiency compared to other conditions. This might due to A. creatinolyticus tolerated to As concentration greater than B. subtilis. In addition, A. creatinolyticus also produced ammonium for enhancing plant growth. Therefore, E. cordifolius inoculated with A. creatinolyticus was suitable to apply in As contaminated water.