Biosorption of aluminum, cobalt, and copper ions by Providencia rettgeri isolated from wastewater.

Twenty-three bacterial isolates from polluted water and soil were screened for heavy metals resistance (i.e., Al(3+), Co(2+), and Cu(2+)). The most potent isolate was identified by morphological characteristics, biochemical tests and confirmed by API20E kits as Providencia rettgeri MAM-4. Removal of Al(3+) from aqueous solution by P. rettgeri is more efficient (∼fourfold) than that by B. cereus ATCC 11778 (a comparison strain) at concentration of 200 mg L(-1) Al(3+). P. rettgeri was able to remove Co(2+) more than B. cereus ATCC 11778 at concentration of 50 mg L(-1) Co(2+). Inoculation of P. rettgeri into clay enhanced significantly the removal of Al(3+), Co(2+), and Cu(2+). P. rettegri MI (mutant strain) was able to tolerate more Al(3+) than that of the parent strain. P. rettgeri was resistant to 7 out of 15 antibiotics tested. P. rettgeri MAM-4 isolated from wastewater had ability to remove Al(3+), Co(2+), and Cu(2+) efficiently from aqueous media; and enhanced significantly metal biosporption by clay. This study has revealed that P. rettgeri could be employed as an effective and economic technology for the removal such metal elements from polluted environment.

Emerging methods and tools for environmental risk assessment, decision-making, and policy for nanomaterials: summary of NATO Advanced Research Workshop.

Nanomaterials and their associated technologies hold promising opportunities for the development of new materials and applications in a wide variety of disciplines, including medicine, environmental remediation, waste treatment, and energy conservation. However, current information regarding the environmental effects and health risks associated with nanomaterials is limited and sometimes contradictory. This article summarizes the conclusions of a 2008 NATO workshop designed to evaluate the wide-scale implications (e.g., benefits, risks, and costs) of the use of nanomaterials on human health and the environment. A unique feature of this workshop was its interdisciplinary nature and focus on the practical needs of policy decision makers. Workshop presentations and discussion panels were structured along four main themes: technology and benefits, human health risk, environmental risk, and policy implications. Four corresponding working groups (WGs) were formed to develop detailed summaries of the state-of-the-science in their respective areas and to discuss emerging gaps and research needs. The WGs identified gaps between the rapid advances in the types and applications of nanomaterials and the slower pace of human health and environmental risk science, along with strategies to reduce the uncertainties associated with calculating these risks.

Characterization of local Egyptian iron ores for use in radiation shielding concrete.

Petrographic, physical, chemical, mechanical, and radioactive characteristics tests were performed on magnetite, limonite, and hematite found in abundance in Egypt to determine their suitability for producing radiation shielding concrete. The contents of uranium and thorium were determined using instrumental neutron activation analysis and gamma spectroscopy. The results obtained using the two methods have shown satisfactory correlation. The tests confirm that magnetite and limonite are suitable as concrete aggregate while hematite is not because of its friable nature and high contents of uranium, thorium, and cobalt.

Environmental impacts of cooling system on Abou Qir Bay.

This study was conducted to evaluate the impacts of cooling water on cooling system of Abou Qir Power Plant and on the receiving Abou Qir Bay. Abou Qir Power Plant is a conventional steam electric power plant located in Alexandria Governorate, Egypt. Water and biota samples were collected monthly from cooling water and Abou Qir Bay over a year. Heavy metals, radionuclide, anions and total hydrocarbons were analyzed in the samples using Instrumental Neutron Activation Analysis (INAA), Gamma-ray Spectrometry (GS), Ion Selective Electrodes (ISE) and Gas Chromatography (GC). The results revealed that the characteristics of inlet cooling water had a tendency to be corrosive to the cooling system. The outlet cooling water complied with Environmental Law 4/1994 in all measured parameters except phosphate, ammonia and total petroleum hydrocarbons. On the other hand, samples from all sites had the lowest annual total count of algae in winter and highest count during summer. There are -ve correlations between algae and heavy metals, hydrocarbons, and radioactivity. Algae correlated highly significantly (p<0.01) with Pb, Cu, Ni, total petroleum hydrocarbons, dissolved petroleum hydrocarbon and uranium. Anabaena Sp. (blue green algae) and Euglina Sp.(flagellate) had highly significant (p<0.01) -ve correlation with heavy metals and natural radioactivity. The accumulation percentage of heavy metals by algae ranged from 22% to 37%, and the highest percent was for uranium and the lowest was for chromium. It is recommended to optimize the addition of polyphosphate inhibitor at inlet cooling water to inhibit corrosion in the cooling system and to avoid increase of Anabaena Sp. in the outlet, and to avoid enhancing algae growth that has a great tendency to accumulate heavy metals, and good housekeeping to avoid oil spills containing hydrocarbons from the power plant to sea water.