الفهرس 
Acknowledgements
History and physicochemical propertiesOnly 14 pages are availabe for public view
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Abstract
Increasing utilization of plastics and canned foods led to search for the chemicals enter in their composition; BPA is one of chemicals that enter in manufacturing of plastic to increase its strength, it also lines the canned food to prevent the reaction of metallic can with food; BPA is an estrogenic compound that its primary effect is the ovary which is the most important organ in female reproductive tract. BPA effects on thyroid gland; pancreas and body weight which resulted in its effects on reproductive system.
This work was carried out to investigate the effects of BPA on the reproductive system of young and adult female rats throught it`s effect on body weight, ovarian and uterine weight, complete blood picture, biochemical assays of the level estradiol; progesterone; testosterone; T3; T4; calcium; insulin and blood sugar and also through the detection of any histopathological changes in ovaries; uterus; thyroid gland and pancrease.
One hundred and twenty female Sprague Dawley rats were divided into two groups (sixty rats were one month old and the others sixty rats were 3 months old). Young and adult female rats were subdivided into two subgroups (treated subgroup orally treated with 330 mg BPA /kg bw dissolved in 5 % ethyl alcohol and suspended in 95 % corn oil and control subgroup orallyexposed to ethyl alcohol and corn oil day by day for 12 weeks.
The obtained results revealed that:
1. The body weight was significantly decreased in all treated young female rats starting from 2 weeks post exposure but in adult female one it was significantly increased in subgroup exposed for 12 weeks in comparison with control female rats.
2. The ovarian and uterine weight showed a significant increase in both treated young female rats at 8, 10 weeks and in adult female one from 4 to 10 weeks in comparison with control. Myometrium thickness was significantly increased in treated young female rats at 4 weeks post exposure then it is significantly decreased after 8 and 12 weeks. In adult female ones exposed for 4, 8 and 12 weeks the thickness of myometrium is significantly decreased.
3. The erythrogram of young female rats showed a significant increase in RBCs count, Hgb concentration and HCT % exposed for 6 and 12 weeks, a significant decrease in MCV and MCH exposed for 10 weeks, a significant increase in RDW % exposed for 4 and 6 weeks and a significant decrease when exposed for 10 weeks. While in adult female rats the result showed that RBCs count, Hgb concentration and HCT % were significantly increased after 4 and 6 weeks, MCV and MCH were significantly increased after 2 weeks while after 12 weeks they were significantly decreased. The leucogram count showed a significant increase in young female rats after 6 and 12 weeks and after 4 and 6 weeks in adult female ones and no significant changes were observed in lymphocyte, neutrophil and eosinophil % in both ages.
4. Estradiol level was significantly increased in young female rats exposed for 10 and 12 weeks, while the result showed a significant decrease in adult female rats exposed for 10 and 12 weeks. Progesterone concentration showed no significant changes during the experiment except it was significantly decreased in adult female rats exposed for 4 weeks. Testosterone concentration was significantly increased in young female rats exposed for 10 and 12 weeks, while in adult female ones no significant changes were observed during the experiment in comparison with control female rats.
5. T3 level was significantly increased both in young female rats exposed from 4 to 12 weeks and in adult female one exposed from 4 to 8 weeks. T4 level was significantly increased in adult female rats exposed from 4 to 8 weeks, while there were no significant changes in young female rats during the experiment. Calcium concentration was significantly decreased from 8 to 12 weeks in adult female rats, although its level showed no significant changes in young female rats during the experiment in comparison with control female rats.
6. Insulin concentration was significantly decreased in young female rats exposed from 6 to 12 weeks; while in adult female rats it was significantly increased from 4 to 12 weeks post exposure. Blood sugar level was significantly increased in young female rats exposed from 8 to 12 weeks; while in adult female one it was significantly decreased from 4 to 8 weeks in comparison with control female rats.
7. Histopathological changes were different in young female rats in comparison to adult.
BPA induced degenerated ovarian follicles, vacuolation of theca cells and polycystic ovary (PCO) in young female rats; while it was induced atertic follicles in adult one. Moreover, BPA led to an increase in thickening of the ovarian surface epithelium and that invagination in young female rats at the 8th week and adult female rats at 10th week post-administration.
The uterine histopathological changes due to BPA were mainly observed in the myometrium and manifested by increasing in the thickness and proliferation of the smooth muscles nuclei; these changes were coincided with the increased weight of the uterus.
The histopathological changes of pancreatic in young female rats showed vacuolation of the endocrine parts, while in adult female rats there was intralobular fatty infiltration.
The histopathological changes in the thyroid glands were showed necrosis of parafollicular cells and inter follicular hemorrhage in young female rats and desquamation of ling epithelium of thyroid follicle in adult female one. In conclusion: All female rats either young or adult are sensitive to the toxic effects of bisphenol A (BPA). It caused different changes on body weight, ovarian and uterine weight, complete blood count and the concentration of estradiol, progesterone, testosterone, triiodothyroinine, thyroxine, calcium, insulin and blood sugar level; which reflecting on female reproduction.
Polycyctic ovary was found in young rats which explain the increase in testosterone concentration in that age,while atretic follicles was shown in adult ones that clarify the decrease of estradiol concentration which related to decrease calcium level in that age. The thickened and invaginated ovarian surface epithetlium in both ages could be related to the increase in thyroid hormones concentration and increase the possibility of ovarian cancer development with the increase of exposure time. Increasing of the proliferation and necrosis of parafollicular cells of thyroid gland shown in young rats and desquamation of lining epithelium of the gland in adult ones indicated the alteration of thyroid hormones. Pancrease vacuolation in its endocrine parts of young rats could indicate the decrease in insulin concentration and the increase of blood sugar level. But intralobular fatty infiltration shown in adult ones which is a typical picture of diabetes could clarify the increase of insulin concentration and the decreas in blood sugar level. Recommendations: Awareness the consumer about the hazard effect of the plastic products that contain BPA.
2- Have a guid map and sterategies to replace BPA and decrease its side effect especially reproductive problem in the animals. Regular monitoring of citizens near BPA plants for early diagnosis of cancer and other diseases resulted from BPA. Regular detection of the level of BPA in food Extera research should be applied on the gene expression affected by BPA. Strict hygienic disposal of industrial waste from BPA manufacturing factories. Avoiding the use of plastic cup, preservation of food and water in plastic containers. Avoiding microwaving of food in plastic containers. Not use canned food except if there is a word of ”BPA free lining” and not use thermal paper especially when our hands is wet. Wear gloves when use printer ink and powdered paints Study the possibility of ovarian cancer as a result of bishenol A exposure with the increase time of exposure. Explore the storage site especially fatty tissue of bisphenol A in the domestic and marine animals and it`s withdrawal period to avoid its hazards effects on human. Develop full toxicological studies to determine the toxic levels and effects of bisphenol A on livestock. 14 Extra studies on the effect of bisphenol A on the thyroid gland and pancreas.