الفهرس 
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Abstract
Bisphenol A (BPA) (4,40-dihydroxy-2,2-diphenylpropane) is an industrial chemical synthesized by condensation of two phenol groups and one acetone molecule.
Sources of exposure include food especially canned food, dust , papers especially thermal because it come with food or due to recycling with other types of papers, dental materials, medical devices and healthcare applications.
Food is the major pathway of general population exposure to bisphenol A due to the migration of bisphenol A from food contact materials into food. Therefore,toxicokinetics after oral administration are considered more relevant for their application to an exposure assessment by biomonitoring and the interpretation of its results. In rodents and in primates, aswell as humans, orally administered bisphenol A is rapidly and efficiently (95% of dose) absorbed from the gastrointestinal tract and undergoes extensive first-pass metabolism in the gut wall and in the liver. During this first-pass metabolism, biotransformation of bisphenol A to bisphenol A-glucuronide is the major pathway of BPA metabolism.
The mechanism of action of BPA is mainly due to binding to estrogren receptors α and β (ERα &ER.(βIt is considered as an exogenous estrogen or has an estrogen mimic effect. It also can bind to other hormone receptors as thyroid hormone receptor.
BPA had many adverse health effects on human. It produces toxic effects on many body systems including skin and metabolism. It has a significant role in producing obesity and there are many studies confirmed the association between BPA and diabetes mellitus and cardiovascular diseases. Also it affects immune system, nervous system and breast cancer.
Its reproductive toxic effect on human male included disruption of sex hormones, sperm quality and motility in addition to alteration of sexual function.
The toxic effect of BPA on the human female reproductive system is the point of interest of this study. It causes many adverse effects as many studies stated the association between BPA exposure and development of PCOS, endometrioses and recurrent miscarriage.It is considered as one of fertility alarming substance category three and it is one of the endocrine disruptive chemicals.
The exact etiologyofuterine leiomyoma developmentremains largely unknown.
This study tried to confirm the toxic effect of BPA on human and animal female reproductive system by dividing the study into two parts. The first part is quantitative estimation of BPA compound in the tissue of human uterine lieomyoma by HPLC technique trying to find the relation between BPA and the pathogenesis of lieomyoma disease.
BPA had been detected in lieomyoma tissue and its adjacent myometrium as a result of the present study without significant difference in the level between the two types of tissues.
On other hand the second part of the study is experimental, it investigated the effect of BPA on the reproductive system of adult female rats. Sixty adult female rats were divided into 3 groups. The first group was the control and it was divided into positive control taking the vehicle, which was corn oil and the other was negative taking nothing except normal feeding. The second group (group I) had taken BPA at dose of 50 mg/kg/day orally for 3 months and the next group is (group II), which had taken BPA at a dose of 150 mg/kg/day orally for three months.
Then both uteri and ovaries were examined histopathologicaly for detection of morphological changes that had produced.
BPA treated groups showed variable degrees of abnormalities in the ovaries and uteri that were dose dependent.Macroscopic observation showed that ovaries from group I(BPA treated animals at dose of 50mg/kg/ day) were smaller and lookedmore or less atrophied compared to control. Histological analysis of the ovaries demonstrated apparent decrease in the number of corpora leutea and significant increase of the number of atretic follicles in group I while ovaries of group II were characterized by significantappearance of atretic follicles specially those forming cysts.
Endometrial changes included decrease in the epithelial height in group I. The endometrial thickness non significantly increased in group I while it increased significantly in group II as compared to positive control groups (C2).
So we could conclude from these results that the exposure to BPA substance that present in plastic containers produces toxic effect on the reproductive health on humans and animals especially on females so the use of these plastic containers should be limited especially those come in contact with food and drinks to protect the health of humans and animals.