RESUMO
This study aimed to investigate the presence/absence of SARS-CoV-2 genome in the air and high-touch surfaces. This cross-sectional study was conducted from late-2020 to mid-2021 in the sections of Intensive Care Unit (ICU), emergency, infectious disease ward, and nursing station of the COVID-19 patient reception center in Kerman, Iran. The presence/absence of SARS-CoV-2 genome in the 60 samples of high-touch surfaces and 23 air samples was analyzed by reverse transcription polymerase chain reaction (RT-PCR). Fisher's exact test was used to compare the number of positive samples in different sampling sites. The genome of SARS-CoV-2 was found in the eight samples (13.32%) taken from the high-touch surfaces (two samples in COVID-19 ICU, two samples in general ICU, two samples in emergency ward, and two samples in nursing station) and two air samples (8.70%) (one sample in the general ICU and one sample in the emergency ward). Statistical analysis showed that there was no significant difference between the type of sampling site and the positive cases of SARS-CoV-2 in the surface samples (p value = 0.80) and air samples (p value = 0.22). According to the results, the SARS-CoV-2 can find in the high-touch surfaces and indoor air of the COVID-19 patient reception centers. Therefore, suitable safety and health measures should be taken, including regular and accurate disinfection of surfaces and equipment and proper ventilation to protect healthcare workers and prevent disease transmission. More studies are recommended to investigate the SARS-CoV-2 concentration in the high-touch surfaces and air samples in the similar researches, efficacy of different disinfectants used on the high-touch surfaces and compare the effect of type of ventilation (natural or mechanical) on the viral load.
RESUMO
Sources of heavy metals (As, Cd, Co, Cr, Cu, Mn, Ni, Pb and Zn) in the road dust of Bandar Abbas city, Iran, and its west suburb were apportioned and the related source-specific ecological and health risks were assessed. The level of heavy metal pollution and the related ecological risk for suburban road dust (suburban RD) were far higher than those of urban RD. Accordingly, probabilistic health risk assessment showed no significant health risk in urban region but significant health risk in the suburb, especially for As with cancer risk above 10-4. Source apportionment using positive matrix factorization (PMF) identified lithogenic source (45.9%) and traffic emission (47.6%) as the main sources of heavy metals in urban and suburban regions, respectively. However, the industrial/construction activities showed the main contribution in ecological risk in both regions. On the other hand, the health risks in urban and suburban regions were mainly attributed to lithogenic source (49.7% for non-cancer risk and 36.8% of cancer risk) and traffic emission (69.4% of non-cancer risk and 46.6% of cancer risk), respectively. The sensitivity analysis showed that the Pb and As originated from traffic emission had the most impact on the non-cancer and cancer risks, respectively, in the suburb. Therefore, this study highlighted the concern about traffic emission as a critical heavy metal source in the road dust of Bandar Abbas suburb.
