Toxicity assays applied to wastewater of 10[th] of Ramadan industrial city, Egypt

The toxic impact of wastewater of 10[th] of Ramadan industrial city [Egypt] on the receiving water body was investigated. Both algal and fish bioassay procedures were applied to the raw and treated wastewaters. In case of raw wastewater the EC50 [96 hours] for the green algae [Scenedesmus obliquus], the diatoms [Nitzschia linearis] and blue green algae [Oscillatoria limnetica] amounted to 29%, 36% and 41%, respectively. In case of Tilapia fish [Oreochromis niloticus]; the LC50 [96 hours] amounted to 13.9%. Treated wastewater did not show toxic effects on algal cultures or Nile Tilapia fish. Exposure of the fish to the raw wastewater induced an increase in the serum content of glucose, AST, ALT activities, creatinine and uric acid compared to the control

Treatment of a combined dairy and domestic wastewater in an up-flow anaerobic sludge blanket [UASB] reactor followed by activated sludge [AS-system]

The feasibility of using an Up-flow Anaerobic Sludge Blanket [UASB] reactor followed by activated sludge [AS-system] for the treatment of wastewater discharged from Dairy factory was explored. The UASB reactor was operated at a Hydraulic Retention Time [HRT] of 24 h and Organic Loading Rates [OLR's] ranging from 1.9 to 4.4 kg COD/m[3].d. Despite variation in OLR, the reactor provided a more or less constant effluent quality of 1385 mg/I for COD total, and 576 mg/l for total BOD5, corresponding to removal values of 69 and 79%, respectively. Total suspended solids [TSS] and volatile suspended solids [VSS] removal averaged above 72 and 75%, respectively. Residual phosphorous and oil and grease concentrations were 8.2 mg P/l and 44 mg/l, respectively, corresponding to removal values of 63 and 83%. This high performance could be attributed to the long Sludge Residence Time [SRT =76 d] imposed to the reactor. Total and faecal coliform counts were reduced by a value of 1.07 and 0.9 log10, respectively. The VS/TS ratio of 0.66 of excess sludge revealed its good quality. Net sludge yield coefficient was found to be around 0.2g VSS per g COD total removed per day, corresponding to 20% of the total influent COD. Preliminary results of activated sludge [AS] batch experiments indicated first order removal kinetics between total organic carbon [TOC] and contact time. The TOC removal reached 98.4% within 2.0h. Accordingly, the AS-system was operated at a HRT of 2.0 h. The AS- step achieved a substantial reduction of COD total, BOD5 total, TSS and oil and grease resulting in residual concentrations of only 35.0, 7.0, 14.0 and 2.8 mg/l, respectively. The geometric mean of total and faecal coliform counts was reduced by a value of 1.28 and 1.64 log10, respectively. The results obtained indicated that the use of an integrated system consisting of UASB followed by an AS-system for the treatment of dairy wastewater could achieve over 98.9% of COD total. 99.6% of BOD5 total and 98.9% of oil and grease

Disseminated neonatal candidiasis in the neonatal intensive care unit

The study included 50 critically-ill newborns with clinical features of neonatal sepsis, selected when having a minimum of 2 of the risk factors known to enhance the development of systemic candidiasis namely, prematurity or low birth weight [90%], prolonged antibiotic therapy [80%], prolonged insertion of intravascular cannulae [70%], gastrointestinal surgery or diseases [38%], use of aminophylline [32%] or steroids [16%] and/or prolonged endotracheal intubation [16%].Candida albicans could be isolated in only one of 35 urine specimens obtained by suprapubic bladder aspiration. All blood samples [obtained from 50 newborns] and CSF samples [from 13 newborns] were negative for C.-albicans inspite of prolonged culture on appropriate media. Disseminated neonatal candidiasis seems to affect a minority [2%] of high risk critically ill neonates. In highly suspicious cases different specimens [Blood, Urine and CSF] should be cultured since the organism may be grown in only one of these specimens