Amal Saad Hussein
Deputy-editor of EJER
Professor of Environmental & Preventive Medicine
Municipal Wastewater Treatment Using Low Cost Treatment Technology in Small Communities
Hala M. Elkamah, Hala S. Doma, Ahmed H. Salem
National Research Center. Water Pollution Research Department, Cairo, Egypt
*Corresponding author: Hala M. Elkamah
The aim of this study is to evaluate the performance of the horizontal flow bio-film reactor in the treatment of municipal wastewater in small communities. Horizontal flow bio-film reactor was designed, constructed and tested for the removal of organic carbon and nitrogen from domestic wastewater. It consists of a stack of 40 horizontal polyvinyl chloride (PVC) sheets embedded with 15 mm deep frustums. The wastewater continuously dosed onto the reactor and flowed horizontally along each sheet and vertically shifted down through the reactor. The system operated for almost 466 days, under four hydraulic loading rates, namely 225.6, 347.7, 451.1 and 582.71 l m-2 d-1. The calculations of the hydraulic rates are based on the Top Plan Surface Area (TPSA) of the reactor. The performance of the treatment system was monitored via complete physico–chemical and bacteriological analysis of both raw and treated wastewater. The overall efficiency of the treatment system resulted in considerable removals of COD (91%), BOD (93%), TSS (92%) and ammonia-Nitrogen (74%). Horizontal Flow Bio-Film Reactor technology could provide a suitable alternative, which can be applied in rural areas and small communities. The system has proved that it has many benefits such as, low cost in manufacturing and maintenance, simplicity of operation, as well as the production of high quality effluent which can be reused in multiple aspects.
Prevalence of Legionella spp. and Helicobacter pylori in different water resources in Egypt
Mohamed Azab El-Liethya*, Bahaa A. Hemdana, Einas H. El-Shatouryb, Mohamed A. Abou-Zeidb, Farag A. Samhana, Gamila E. El-Taweela
aBacteriology Lab., Water Pollution Research Department, Environmental Research Division, National Research Centre, Dokki, Giza,12622, Egypt. bMicrobiology Department, Faculty of Science, Ain Shams University. El- Khalifa El-Mamon St., Abbassia, Cairo, 11566, Egypt
The main objective of this investigation was to detect Legionella spp. and Helicobacter pylori in different types of water resources. One hundred seventy five different water samples were collected from Egypt. Water samples were collected from Nile River (Rossita Branch), the Mediterranean Sea at Marsa Matroh shore, El-Rahawy Drain, hospital wastewater and groundwater. Legionella spp. and Helicobacter pylori were determined using membrane filtration and spread plate techniques. Legionella spp. and H. pylori were detected using culture methods on selective media in 25 and 33% of the total examined water samples, respectively. The biochemical tests for Legionella spp. showed that, 6 (35%) out of 17 might belong to L. pneumophila and 4 (23%) out of 17 belonged to non-pneumophila Legionella species. Eight out 27 (29%) isolates showed positive results for urease, catalase, oxidase, motility tests and negative nitrate reduction were confirmed as H. pylori. The results concluded that further monitoring and identification should be carried out in the future for the presence pathogens in water resources.
Environmental and Occupational Medicine Department, National Research Centre
Tobacco use is common throughout the world and is growing faster in low-income countries due to steady population growth and the tobacco industry targets this vulnerable population, in addition to the low prices, lack of awareness about its dangers, and aggressive and widespread tobacco company marketing.
A global survey of tobacco use among adults in Egypt (2009), found that nearly 30% of Egyptians are consumming one of the tobacco products; in form of 16% cigarettes, 3.3% shisha and 2.6% tobacco chewed. Also the survey in 2009 proved that workers in 61% of the closed working places, 80% of public transport users and more than 70% of the visitors to shopping centers and government buildings and non-governmental organizations are exposed to secondhand smoke (passive smokers).Read more...