Evaluation of Indoor Air Quality in Medical and Residential Areas, Damietta, Egypt

Abstract

Indoor air quality plays a significant role in the health of people as they spend most of their time in the indoor environment. Particulate matter is one of the most important indoor air pollutants involved in a number of adverse health effects. Both indoor and outdoor concentrations of particulate matter (PM10) and heavy metals (Pb, Zn and Cd) in addition to bacterial concentrations were determined at fifteen medical sites and twenty residential sites from May to August 2021. PM10 was measured by CEL-712 Micro dust Pro Real-time Dust Monitor HB4048-01 while heavy Metals concentrations as Pb, Zn and Cd were measured using Accuses 211 Flame atomic absorption spectrometry. The PM10 concentrations measured in all the medical sites located in the urban area were ranged from 4273 to 9802 μg/m3 indoors and from 4473 to 9815 μg/m3 outdoors. On the other hand, those located in the suburban area have PM10 concentrations ranged from 3456 to 8847 μg/m3 indoors, and from 3505 to 8883 μg/m3 outdoors. In residential sites, the PM10 concentrations for those in the urban area were ranged from 4792 to 9797 μg/m3 indoors and from 4945 to 9832 μg/m3 outdoors. While those located in the suburban area have PM10 concentrations ranged from 2461 to 7518 μg/m3 indoors and from 2683 to 7592 μg/m3 outdoors. The mean concentration of Pb, Zn and Cd through all the sampling sites was 0.537, 2.540 and 0.038µg/m3, respectively. Bacterial concentration was measured using gravitational and filtration method. Through all sites, five bacterial species were isolated from the indoor and outdoor air; Bacillus species, Lactobacillus Sp., Pseudomonas putida, Staphylococcus aureus and Staphylococcus xylosus. The mean total bacterial count collected by gravitational method is 15712 CFU/m3. While those collected by filtration method is 27689 CFU/m3 through all the sampling sites. Additionally, the most I/O ratios of PM10, Pb, Zn, Cd and Bacteria at the most sites were below 1.0 and that indicates the relatively higher influence of the outdoor sources on the indoor air. All measured pollutants were higher in medical sites than in residential sites. It is recommended to improve the indoor air quality. Therefore, it is necessary to open doors and windows to provide natural ventilation and to clean indoor space using more natural cleaning materials.