الفهرس 
AcknowledgementOnly 14 pages are availabe for public view
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Abstract
There is an increasing public concern about environmental risks because many human ivities are detrimental to the natural environment, and in turn, environmental changes ty lead to many health consequences. The word “environment” has a meaning of :ation, i.e., “place,” in terms of certain geographical and physical characteristics, iwever, at the same time, it is also a social concept reflecting the social/economical velopment of a given location, the qualitative criteria of living conditions of that :ation. Both of these interpretations are justified as having important effects on health luharet al., 2009)(1).
Pesticides comprise a variety of toxic substances, and are used in agriculture as well as
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loors to kill pests (Bazrafshanet al., 2007) . All pesticide compounds pose anvironmental health hazard as they are, to greater or lesser degree, chemically tailored to
toxic and persistent (Foster and Chilton, 2003)(3). The health risk of pesticides to mans is worsened by the fact that many of ”hese substances have been shown to be Btagenic and carcinogenic (Zohair, 2001)(4). Pesticide poisoning is an important cause of Drbidity and mortality in developing countries although only one-fourth of the total world nsumption of pesticides has been reported from these regions. Nevertheless, every year 2re are three million cases of severe poisoning and 220,000 deaths; the majority of these lisonings and 99% of the resulting deaths occur in the third world (Tinoco and Halperin, >98)(5).
Pesticides are released into the environment in large quantities each year and are utinely detected in air, dust, ground water, and body tissues of animals and humans, [any pesticides are lipophilic and bioaccumulate in lipid stores and tissues such as in ammary glands or adipose tissues. They are mobilized along with the lipids during egnancy and lactation, and may be passed io the developing fetus or offspring via acental transfer and milk (Pages et al., 2002)w. Pesticides may induce oxidative stress, ading to generation of free radicals, oxygen free radicals (Nasiret al., 2008)(7).
Free radicals are defined as atoms or molecules that contain one or more unpaired ectrons (Florence, 1990)(8-. While, Oxidative stress can be defined most simply as the ibalance between the production of free radicals capable of causing peroxidation of the pid layer of cells and the body’s antioxidant defense (Ranjbaret al, 2006)(9). Pesticides :oducing radicals such as paraquat, diquat and the organochlorine pesticide lindane, rganochlorine pesticides present special toxicological problem due to their long ;rsistence and ability to accumulate in adipose tissue (Saradha and Mathur, 2006)( 10).
t Normal cellular function depends on a balance between reactive oxygen species (ROS) roduced and antioxidant defense mechanisms available to the cell. Reactive Oxygen pecies, including the superoxide radical, hydrogen peroxide, and the hydroxyl radical, rise as by-products of normal cellular metabolism or may be the consequence of exposure ) certain toxicants. In such cases of overwhelmed antioxidant defense, cellular function an be affected and cells may be damaged (Kerr a al., 1996)(1 n.
All the ROS are free radicals which are defined as any chemical species that possesses n unpaired electron or odd number of electron. Free radicals exist in a state of kermodynamic instability. They are highly reactive and search to combine with another lolecule to pair off its lone electron (Jeffery et al., 1999)<12). There is considerable