http://etd.aau.edu.et:80/dspace/handle/123456789/444 Search the Channel search http://etd.aau.edu.et:80/dspace/simple-search http://etd.aau.edu.et:80/dspace/handle/123456789/950 Title: Toxicological Study of Glinus lotoides and Hagenia abyssinica: Traditionally used Taenicidal Herbs in Ethiopia <br/> <br/>Authors: Demma, Jemal <br/> <br/>Abstract: Seeds of Glinus lotoides, Linne (Molluginocea) and flowers of Hagenia abyssinica Gmel, (Rosaceae) are used traditionally in the treatement of tapeworm infestion in Ethiopia. Previous studies on anthelmintic activities of both plants have confirmed their traditional claims. However, their detailed toxicities were not yet conducted. In these studies, single and repeated dose oral toxicity studies in rats were conducted using methanolic extracts of seeds of Glinus lotoides and aqueous extracts flowers of Hagenia abyssinica. Doses of 0, 1000 and 5000 mg/kg of crude extract of Glinus lotoides were employed in single dose toxicity study while doses of 0. 250, 500, and 1000 mg/kg were used in repeated dose toxicity studies. In the single dose toxicity test, oral administration of 5000 mg/kg of Glinus lotoides produced mortality in two females and one male on day 4. No significant differences in body and organ weight between controls and treated animals were observed in survived animals at both dose levels. Therefore LD50 of the extract might be greater than or equal to 5000 mg/kg. Moreover, both gross and microscopic examinations of organs did not show detectable differences between controls and treated animals of both sexes. In repeated dose toxicity studies, no mortality was observed when these varying doses of the extracts were administered per day for a period of 28 days. There were no significant differences in the body weight, absolute and relative organ weights between controls and treated animals of both sexes. Hematological analysis showed no differences in most parameters examined. In the clinical chemistry analysis, no significant change occurred. Pathologically, neither gross abnormalities nor histopathological changes were observed. Therefore, the NOEL could be greater than or equal to 1000 mg/kg in rats and none of the organs are considered target during both single and repeated studies. The aqueous flower extracts of Hagenia abyssinica was tested for its single and repeated dose toxic effect on rats of both sex. Studies at 5000 mg/kg (limit test) and at three dose levels (500, 1000, and 2000 mg/kg) for the main study were conducted orally on 5 rats per sex per dose with concurrent control receiving distilled water in single dose study. No toxic sings were noted at all dose levels and there were no significant differences in mean body weights of the treated group compared to control. Therefore, LD50 of the extract is greater than 5000 mg/kg. In repeated dose studies, three doses of the extract (350, 750, and 1500 mg/kg) were administered orally to 5 rats per dose per sex for 28 days and various toxicologic indices tested. Cage side observation, body weight, biochemical and morphologic pathology observation did not show significant differences across the group. Therefore, none of the organs have shown to be the target; Hagenia abyssinica is safe in rats at all doses studied and the NOEL could be greater than or equal to 1500 mg/kg in rats. <br/> <br/>Description: A Thesis Submitted to the School of Graduate Studies of Addis Ababa University In Partial Fulfilment of the Requirements for the Master of Science Degree in Toxicology Thu, 24 Apr 2008 14:13:48 GMT http://etd.aau.edu.et:80/dspace/handle/123456789/598 Title: LEAD EXPOSURE STUDY AMONG WORKERS IN LEAD ACID BATTERY REPAIR UNITS OF TRANSPORT SERVICE ENTERPRISES ADDIS ABABA, ETHIOPIA <br/> <br/>Authors: AHMED, KEMAL <br/> <br/>Abstract: Lead exposure is common in automobile battery manufacture and repair, radiator repair, secondary smelters and welding units. Urinary Aminolevulinic acid has validity as a surrogate measure of blood lead level among workers occupationally exposed to lead. This study had therefore assessed the magnitude of lead exposure in battery repair workers of three transport service enterprises. To this effect, a cross-sectional study was carried out on lead exposure among storage battery repair workers between November and May 2005 from Anbasa, Comet and Walia transport service enterprises, Addis Ababa, Ethiopia. Subjective information from the workers was obtained by making use of structured questionnaire. Other information was obtained from the walkthrough evaluation of the repair units. Aminolevulinic acid levels in urine were used as an index of the exposure. This was coupled to measurements of other relevant parameters in blood and urine collected from adult subjects working in the repair units as well as age matched control subjects that were not occupationally exposed to lead. Aminolevulinic acid was determined by spectrophotometry, while creatinine clearance, serum creatinine, urea and uric acid levels were determined using AMS Autolab analyser. Urinary Aminolevulinic acid levels were found to be significantly higher in exposed group (1.6 mg/dl+ 0.2) compared to the non-exposed ones (0.7mg/dl+ 0.1) (p<0.001). Alcohol taking exposed subjects exhibited a significant increase in urinary aminolevulinic acid levels than non-alcohol taking ones (p < 0.05). Moreover, urinary aminolevulinic acid levels of exposed subjects increased with age (p<0.001) as well as duration of employment (p<0.001). Whereas, serum uric acid levels of exposed subjects was significantly higher than non-exposed ones (p<0.05), no statistically significant difference had been found in renal indices and other measured parameters between exposed and non-exposed subjects. From the questionnaire responses and walkthrough observations, it was known that all the repair units do not implement effective preventive and control measures for workplace lead exposure. Taken together, these findings indicated that workers in lead acid battery repair units of the transport service enterprises are not safe from excessively high lead exposure. Thus, strict enforcement of appropriate and cost-effective preventive and control measures is required by all the <br/> <br/>Description: A Thesis Submitted to the School of Graduate Studies of Addis Ababa University In Partial Fulfilment of the Requirements for the Master of Science Degree in Toxicology Sat, 19 Apr 2008 08:19:06 GMT