Heavy metals phyto-assessment in commonly grown vegetables: water spinach (I. aquatica) and okra (A. esculentus).
The growth response, metal tolerance and phytoaccumulation properties of water spinach (Ipomoea aquatica) and okra (Abelmoschus esculentus) were assessed under different contaminated spiked metals: control, 50 mg Pb/kg soil, 50 mg Zn/kg soil and 50 mg Cu/kg soil. The availability of Pb, Zn and Cu metals in both soil and plants were detected using flame atomic absorption spectrometry. The concentration and accumulation of heavy metals from soil to roots and shoots (edible parts) were evaluated in terms of translocation factor, accumulation factor and tolerance index. Okra recorded the highest accumulation of Pb (80.20 mg/kg) in its root followed by Zn in roots (35.70 mg/kg) and shoots (34.80 mg/kg) of water spinach, respectively. Different accumulation trends were observed with, Pb > Zn > Cu in okra and Zn > Pb > Cu in water spinach. Significant differences (p < 0.01) of Pb, Zn and Cu accumulation were found in both water spinach and okra cultivated among tested treatments. However, only the accumulation of Pb metal in the shoots of water spinach and okra exceeded the maximum permissible levels of the national Malaysian Food Act 1983 and Food Regulations 1985 (2006) as well as the international Codex Alimentarius Commission limits. This study has shown that both water spinach and okra have good potential as Pb and Zn phytoremediators.
Faculty of Science, Institute of Biological Sciences, University of Malaya, Kuala Lumpur, Malaysia.
Chuck Chuan
CC
Ng
Faculty of Science, Institute of Biological Sciences, University of Malaya, Kuala Lumpur, Malaysia ; Department of Plant Agriculture, Ontario Agricultural College, University of Guelph, Ontario, Canada.
Md Motior
MM
Rahman
Faculty of Science, Institute of Biological Sciences, University of Malaya, Kuala Lumpur, Malaysia.
Amru Nasrulhaq
AN
Boyce
Chemistry Department, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.
Mhd Radzi
MR
Abas
Contamination; Heavy metal accumulation; Okra; Water spinach