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Bioaccumulation of metals
from tannery sludge by Typha angustifolia L.
Firdaus-e-Bareen* and Sheza Khilji
Department
of Botany, University of the Punjab, Lahore -54590,
Pakistan.
*Corresponding author. E-mail:
fbareen@gmail.com.
Tel: 92-42-7024999, 92-42-5884513.
Accepted
5 May, 2008 |
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The metal bioaccumulation capability of a common anchored
hydrophyte, Typha angustifolia L. was studied in a
green house trial. The plants could absorb significant
amounts of the heavy metals like chromium, copper and zinc
from tannery sludge. Different concentrations of tannery
sludge were prepared in water and plants of T.
angustifolia were exposed to the sludge for 30, 60 and
90 days. A significant reduction in sodium chloride
percentage, chlorides and chemical oxygen demand (COD) was
observed. The percentage reduction in all metals was
significant. Cadmium and lead were found to be totally
absent. A greater reduction of metals was observed in 30%
concentration of sludge. A maximum reduction of 62% for Na,
42% for Cr, 38% for Cu and 36% for Zn was observed in 30%
sludge after 90 days exposure of T. angustifolia. The
bioaccumulation potential of T. angustifolia was
greater for the heavy metals especially for Cr. The maximum
metal uptake, observed after 90 days exposure of T.
angustifolia, was 6,698 mg kg-1 for sodium,
20,210 mg kg -1 for chromium, 16,325 mg kg
-1 for zinc and 7,022 mg kg -1 for copper
in the roots. In shoots, the uptake was 3,745 mg kg-1
for sodium, 10,150 mg kg-1 for chromium, 3,509 mg
kg-1.for copper and 7,025 mg kg -1 for
zinc. Aerial parts of T. angustifolia accumulated
less heavy metal than the corresponding roots. T.
angustifolia is suitable for the decontamination of most
of the harmful metals from tannery sludge.
Key
words:
Bioaccumulation, tannery sludge, heavy metals, Typha
angustifolia. |
