Pb Removal from Contaminated Water Using EDTA with Colocasiaesculenta (L.) Schott at Klity Creek, Kanchanaburi, Thailand

Abstract

This study investigated lead (Pb) removal using a plant called‘Elephant Ear’ (Colocasiaesculenta (L.) Schott) from contaminated waterat Klity Creek, located in Kanchanaburi Province, Thailand. Plants weregrown in contaminated water with lead carbonate (Pb(CO₃)₂) in a nursery. The experiment was divided into 4 sets; (1) With Pb but without EDTA, (2) With Pb and EDTA 0.01 millimole (mM) per liter (mM L^-1), (3) With Pband EDTA 0.02 mM L^-1 and (4) With Pb and EDTA 0.03 mM L^-1. These plants were grown, maintained and harvested every 15, 30, 45, 60, 75 and 90 days. Plant samples were separated into three parts; leaf, petiole and root. They were analyzed in terms of total lead (TPb) content, including the water solution. The results showed that Pb accumulation in Elephant ear was relatively significant in all of the experiment sets (p<0.05) at 15 days. The results showed that Pb accumulation in the whole plant was highest at 90 days. This study showed that Pb absorption in plant was enhanced when the concentration of EDTA increased. Plants showed that Pb accumulation in roots > petioles > leaves were significant with 502.84, 126.19 and 91.06 mg kg^-1 (p<0.05) at EDTA of 0.02 mM set, respectively. Plants exhibited signs of phytotoxicity, such as wilting and curling of their leaves, yellow color appearing in the leaf margins and the plants eventually dying. These effects could be used as an indicator for determining the presence of Pb in contaminated water and soil.