الفهرس 
Study Area and its SignificanceOnly 14 pages are availabe for public view
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Abstract
Chemical pesticides are well recognized as an economic approach
to control pests, at the same time such chemicals are highly toxic to
other species in the environment. Now there is growing concern
worldwide over the indiscriminate use of such chemicals, which result
in environmental pollution and toxicity risk to non-target organisms.
Most of pesticides find their way into rivers, lakes and pond, and have
been found to be highly toxic not only to fishes but also to the
organisms which contribute to the food chain of fishes. Therefore,
investigations on the effects of the pesticides in fish have a diagnostic
significance in the evaluation of adverse effects of pesticides to human
health. Some of the pesticides are persistent in the environment and
their presence cause acute toxicity to fish. Several studies have shown
that minute concentrations of pesticides, especially organochlorines, are
toxic to biological organisms and they threaten ecosystem integrity due
to their stable structure and lipophilic character. They also tend to
bioconcentrate, bioaccumulate and biomagnify and are transferred to
higher trophic levels through several food chains, leading to vertebrate
and non-vertebrate toxicity in non-target organism and even humans.
Despite this, there is very limited data on the distribution of pesticides,
especially synthetic pyrethroids in various environmental media in
Egypt. Fishes are often at the frontline of manifesting toxicological
effects when exposed to pesticides in aquatic ecosystems, hence are
suitable bioindicators of environmental pollution.