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Introduction: Frequent touch surfaces encountered in shopping malls can play a role in transmission of microbial pathogens and the dissemination of infectious diseases. This study aims at assessing the bacterial contamination of such surfaces in 4 large shopping malls in Sharjah, UAE. Materials and Methods: A total of 224 samples were collected from 4 different malls in Sharjah, UAE, in 2014, using sterile cotton swabs. The swabs were transferred and spread on Nutrient agar plates and incubated for 48 hours at 37°C. Colony forming units (CFUs) were counted for each plate, then isolated and identified using colony morphology, differential staining, and growth capabilities on different types of media. Results: Out of all collected samples, 192 (amounting to 86%) were positive (contaminated with bacteria). In each mall, more than 80% of all sampled surfaces were contaminated with bacterial growth. The highest bacterial density was found on food courts’ trays, food courts tables’ surfaces, and food tray handles. Comparing the average bacterial count from all surfaces in the 4 different malls under study, a significant result was observed, with one-way repeated measures ANOVA yielding the following: F(3) = 3.42, p = 0.024. The highest mean bacterial counts were in the malls with the highest numbers of visitors/m2. Conclusion: Nearly, every single sampled surface yielded a moderate to heavy degree of bacterial contamination. This is cause for concern, because infection risk depends to a large extent on infectious doses of pathogens. Consequently, cleaning services in shopping malls should be improved, and the public should be educated on the best hygiene-related precautions to be taken in malls.

In this study, Al-Qateef wastewater treatment plant was selected as a case representing the upgrade of carrousel technology with tertiary treatment. This technology is applied in many cities in the Eastern province, Kingdom of Saudi Arabia. The use of chemical treatment alternative for phosphorous removal was evaluated versus the newly implemented tertiary treatment unit. The study showed that chemical phosphorous removal has an additional advantage of reducing the final effluent total phosphorus concentration to less than 1 mg/L at an alum dose of 50 mg/L without any significant alteration of the expected final effluent quality that could be achieved by the newly installed sand filters. Furthermore, the study showed that the use of chemical treatment for phosphorous removal could reduce the chlorine dose required for the treated effluent disinfection.