الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
”Discharging untreated industrial effluents in water canals used for irrigation and/or watering livestock is a major problem. The study was carried on the quality of effluent samples collected directly from the discharge point of effluents of MRI company to know its validity for crop irrigation and cattle drinking by evaluating physicochemical characteristics, irrigation indices and heavy metal concentrations in collected samples. The study was also extended to examine the health effects of prolonged ingestion of drinking water containing MRI effluent at concentrations of 10%, 50% and 100% on albino male rats. Ca- alginate was used in the treatment of MRI effluent, showing effectiveness in absorbing heavy metals after 5 hours, and improvement of health effects caused by drinking MRI effluent concentrations. The mean EC values of untreated effluent samples (EF) were within the WHO for drinking water (0.4 dS/m) and FAO limits for irrigation water (0.7-3 dS/m). The mean pH-values of the untreated effluent samples were below the permissible limits recommended by the WHO for drinking water (6.5 –8.5) and FAO for irrigating water (6.5 – 8.4). The mean values of HCO3- in untreated and treated effluent samples were within the permissible limits of WHO for drinking water (150 mg/L) and FAO for irrigation water (600 mg/L). Sodium levels in all water samples were above the WHO drinking water limits (200 mg/L) but were within FAO irrigation limits (920 mg/L). The obtained COD data for untreated and treated effluents exceeded the permissible drinking water levels of the WHO (250 mg/L). According to irrigation water quality criteria, the values of the most investigated irrigation indices (SAR, KR, Na%, and PI) referred to the unsuitability of discharged effluents for irrigation purposes, except MAR%. The study showed obvious concentrations of heavy metals in EF samples, arranged descendingly as Mn, Fe, Zn, Cd, Co, Ni, Pb, Cu, and Cr. Most of the detected heavy metals in MRI effluents exceeded the WHO limits for drinking water. The study showed a significant increase in the accumulation of heavy metals in the liver of MRI effluent groups depending on effluent concentration. The present study showed significant elevations in ALT, AST, and TB levels especially at 50%.EF and 100%.EF groups. In addition, there was a significant reduction in TP and Alb in all MRI effluent exposed groups. The obtained data showed obvious decrease in liver antioxidant activities of SOD, CAT, GST, and GSH content with increasing MRI effluent concentrations compared to the control group, mostly with 50%.EF and 100%.EF groups. The present study illustrated a significant reduction in GH, T3 and T4 hormones, as well as a significant elevation in TSH levels with increasing effluent concentrations (10%, 50%, 100%). The present results recorded a decrease in the body weight of rats that received different effluent concentrations. This decrease appeared significant after the sixth week of effluents consumption until the end of the experiment (the eleventh week), especially at 100%. The investigated hematological parameters (RBCs count, Hb content, Hct%, MCV, MCH, MCHC and WBCs count) decreased significantly with increasing concentrations of MRI effluents in drinking water especially at 50% and 100% EF concentrations. The stained hematoxylin-eosin liver and thyroid sections of the rat group that received 10%Ef showed little alterations. In the liver sections, damaged central veins, highly degenerated hepatocytes appeared as foamy areas with sever necrosis, cellular infiltration and pyknotic nuclei were observed in 100%.EF group compared to control. In the thyroid gland sections, formation of microfollicles with reduced lumen and colloid was observed with appearance of hyperplastic follicular cells with large nuclei and inflammation between cells.