Jan 01 1999 - Physiology Web Site

Birds As Bioindicators of Ecotoxicological Effects of Heavy Metal Pollution

J.Anim.Morphol.Physiol Vol 46, Nos 1 & 2, pp1 to 22, 1999

Dedicated to the memory of the late Bhupendra Patel ( Health Physics Division , Bhabha Atomic Research Centre, Bombay), friend and former student, whose untimely death has left a void in the field of ecotoxicology

By J.C.George

Department of Zoology , University of Guelph, Guelph, Ontario, Canada N1G 2W1
Fax: (519) 767-1656; email: jgeorge@uoguelph.ca

The Journal of Animal Morphology and Physiology and PAVO, The Indian Journal of Classical Ornithology and Avian Physiology are the organs of The Society of Animal Morphologists and Physiologists, Department of Zoology, M.S. University of Baroda, Vadodara, 390002, India

ABSTRACT

Heavy metals, in trace amounts, are essential constituents of the living system. With the large increases in their concentrations in the environment from natural as well as anthropogenic sources, they cause serious adverse effects on all forms of life and birds are no exception. Birds like any other animal group, are a product of evlution and possess distinctive features of their own and have the capacity to adapt to changes in an ever-changing environment. Their diversity, mobility and ubiquitous occurrence and survival in diverse environments, qualify them as unique bioindicators of heavy metal toxicity. Heavy metal residues accumulate in the organs and tissues and are even transported to eggs and nestlings. Their toxicity, has profoundly adverse effects on the health and mobility of birds. However, the avian body does respond to contain these effects by synythesizing a metal-binding protein, metallothionein, which renders the metal residues innocuous. It also tries to eliminate metal residues via renal and extrarenal excretion. In addition, elimination of substantial amounts of the metals, is accompolished through moult, a process of integumentary storage excretion which is a reptilian legacy.

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