الفهرس 
acknowledgementOnly 14 pages are availabe for public view
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Abstract
Alexandria is divided into six districts. It has a population of about 3.5 million. The amount of domestic solid waste of the city reaches approximately 1,720 tons/day and the street solid waste is about 1050 tons/day. In Alexandria, there are many SOlll”ces of hazardous wastes. One chief difficulty in monitoring and controlling these hazardous wastes is that they are disposed in an irregular fashion. The present study was planned to supply the basic information needed for management and assessment of these hazardous wastes in Alexandria city. The generation rate of hazardous liquid and solid wastes of a single small activity enterprises is very small. But the great number of these small activities in Alexandria aggravate the problem. The hazards of these wastes go unrecognized or are ignored. Most of the small activity enterprises store the hazardous liquid wastes in plastic containers and dispose of it at the end of the day. Some of them as printing and electroplating are storing it for several days. Most of these activities store their hazardous solid wastes in a receptacles inside the shop and dispose of it at the end of the day into the commWlal containers. None of the 37 activities surveyed was transporting its waste. Most of solid wastes whether from the households or from small activities enterprises find their way to domestic solid waste system, some are sold, a small amoW1t is open burned, and other wastes may be thrown in the streets. Most of the hazardous liquid wastes enter the sewerage system except oil waste nom service stations, and developing wastes nom photographic labs. In addition, working environment includes many health hazards. Assessment of existing knowledge in Alexandria small activity enterprises and houses shows that hazardous effects of hazardous constituents are not well known. The results of the chemical analysis indicated that pollutants discharge into the sewerage system surpassed the limits stated by Decree No 9/1989. Two approaches have been carried out to detect the generation rate of household hazardous wastes. The first included surveying of 20 houses. The second was to segregate a large amount of domestic solid waste at the disposal site. This amoWlt represented about 6200 families. Seven components representing hazardous wastes are present, and their percentage in total has an average of about 3.910/0. After ignoring wood, saw dust, broken glass, metals, burned lamps, and the containers in which the hazardous residues are discarded, the percentage was in the line with most of the results mentioned in the literature «10/0). The generation rate of these wastes after ignoring the aforementioned less hazardous components was 920 g/c/year and for the city was 3,210 tons/year. The final end point of these hazardous components is the dump sites or the compost plant. The effect will be on the untrained workers, nearest underground water, the farmers, and/or the land fertilized with the compost. In Egypt, there is no specific legislation concerning small quantities of hazardous wastes. Recently, the Act No 4/1994 concerning ”Protection of the Environment” has been issued to control all types of environmental pollutants including hazardous wastes. Nonetheless, the problem of household hazardous wastes has not been addressed. Oxygen uptake rate (OUR) test was used to study the effect of different concentrations of 18 waste samples. Some of these samples (representing electroplating, photographic, and printing) were collected nom the field and the others were prepared synthetically. The results obtained with the different slug doses prove the importance of the rapid OUR test which is carried out only for one hour and which is suitable to measure the toxicity of the different wastes whatever their concentrations. The reduction in both OUR and OUR ratio measurements indicates the toxicity of the wastes in addition to the synergistic effect of the heavy metals content of the waste in dealing with the microorganisms of the activated sludge. . It is evident from the results of the synthetic samples and samples collected from the field that with the increasing in the concentrations of the waste, synthetic samples tend to be more toxic while the collected one tend to be not toxic. The bioassays experiments were carried out on 10 samples represent the wastes of photographic, printing, service station, and electroplating activities. All tested wastes were proven to be effective in inducing significant increases in chromosomal aberrations that were found in somatic cells as well as in gonadal ones, giving an evidence that these wastes are toxins. It has been concluded that biomonitor assays are considered to be sensitive, in screening toxicity and genotoxic effects, more than that of chemical ones. However, best of all, the present work recommends that the bioassays as well as the chemical ones should together be used in order to screen the toxicity, cellular and/or genotoxic, of environmental pollutants. Five sets of shock load and long term exposure of synthetic electroplating and photographic waste samples were studied by batch activated sludge using OUR. The results of all the sets studied W1der shock load indicate that the OUR is a LC.!. good indicator in identifying the toxicity of the waste. It has been found that with the increase in the concentration of the waste, the OUR and OUR ratio decreased. The same situation has been obtained with the long tenn exposure . which indicate the poorness of the acclimation process to all of the sets. The removal of the metals was completed within 15 minutes from the starting of the experiment. It also indicates the preference of absorbing the metals by the Mo. This may reveal that the process of acclimation didn’t succeed in changing the response of the Mo in removing these heavy metals from the waste because the process of removal depends mainly on the adsorption. In the present study, Michael constant (Km) was zero for all the samples before acclimation except the second electroplating waste sample with constituents of Cr and Ni while the mmomum oxygen uptake rate (Vmax) was small (8.89 18.66). This indicates the state of non-competitive inhibition. With the .remaining samples, the Vmax never reaches its highest limits which show a feedback inhibition state, in which the product of a metabolic pathway inhibits the initial enzymes of the pathway. A proposal for hazardous waste management program was suggested.^leng