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Chromium Accumulation and
Toxicity in
Aquatic Vascular
Plants
by Prakash Chandra & Kamla
Kulshreshtha (India)
The
indiscriminate discharge of spent waste of chromium based industries has become
a serious global concern as it has created an acute scarcity of safe drinking
water in many countries including India. The problem of chromium poisoning
among leather tanners has long been known. The workers suffer from ulcers,
allergic dermatitis, lung cancer and liver necrosis due to prolonged contact
with chromium salts.
Aquatic vascular
plants play an important role in the uptake, storage and recycling of metals.
The uptake of metals depends on the chemical form present in the system and on
the life form of the macrophytes (floating, rooted or rootless). While
submerged species showed higher chromium accumulation, emergent species also
showed moderate accumulation.
At biochemical
level, chromium toxicity caused reduction in the rate of photosynthesis and
decrease in chlorophyll pigments. Chromium induced morphological and
ultra-structural changes reported in several vascular plants (Lemna minor,
Ceratophyllum demersum, Limnanthemum cristatum) are quite characteristic
and may serve as indicators of chromium pollution.
(For more
details see: Botanical Review vol. 70, No. 3, pp.
313-327, 2004)
Dr.
Prakash Chandra is a
former Scientist & Head, Aquatic Botany Laboratory, National Botanical Research
Institute, Lucknow, India;
Dr. Kamla Kulshreshtha
is Scientist & Head, Eco-education Division at NBRI. |
