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Bioburden in sleeping environments from Portuguese dwellings
2021
Viegas, Carla | Dias, Marta | Monteiro, Ana | Faria, Tiago | Lage, Joana | Carolino, Elisabete | Caetano, Liliana Aranha | Gomes, Anita Quintal | Almeida, Susana Marta | Verde, Sandra Cabo | Belo, Joana | Canha, Nuno
A wider characterization of indoor air quality during sleep is still lacking in the literature. This study intends to assess bioburden before and after sleeping periods in Portuguese dwellings through active methods (air sampling) coupled with passive methods, such as electrostatic dust cloths (EDC); and investigate associations between before and after sleeping and bioburden. In addition, and driven by the lack of information regarding fungi azole-resistance in Portuguese dwellings, a screening with supplemented media was also performed. The most prevalent genera of airborne bacteria identified in the indoor air of the bedrooms were Micrococcus (41%), Staphylococcus (15%) and Neisseria (9%). The major indoor bacterial species isolated in all ten studied bedrooms were Micrococcus luteus (30%), Staphylococcus aureus (13%) and Micrococcus varians (11%). Our results highlight that our bodies are the source of the majority of the bacteria found in the indoor air of our homes. Regarding air fungal contamination, Chrysosporium spp. presented the highest prevalence both in after the sleeping period (40.8%) and before the sleeping period (28.8%) followed by Penicillium spp. (23.47% morning; 23.6% night) and Chrysonilia spp. (12.4% morning; 20.3% night). Several Aspergillus sections were identified in air and EDC samples. However, none of the fungal species/strains (Aspergillus sections Fumigati, Flavi, Nidulantes and Circumdati) were amplified by qPCR in the analyzed EDC. The correlations observed suggest reduced susceptibility to antifungal drugs of some fungal species found in sleeping environments. Toxigenic fungal species and indicators of harmful fungal contamination were observed in sleeping environments.
اظهر المزيد [+] اقل [-]Investigation and disinfection of bacteria and fungi in sports fitness center
2021
Boonrattanakij, Nonglak | Yomchinda, Sirikorn | Lin, Fang-Jia | Bellotindos, Luzvisminda M. | Lü, Mingjun
This study investigated the air quality improvement in terms of bacterial and fungal contamination in an exercise room of a fitness center under normal operating conditions. Environmental conditions including air conditioning, ventilation, moisture, CO₂, particulate matters, and total number of users were also recorded. In addition, fungal and bacterial load were assessed and disinfection on sports equipment surface was also examined. Background bacteria and fungi densities in bioaerosols were in the range of 249 ± 65 to 812 ± 111 CFU/m³ and 226 ± 39 to 837 ± 838 CFU/m³ in the exercise room of the fitness center and 370 ± 86 to 953 ± 136 CFU/m³ and 465 ± 108 to 1734 ± 580 CFU/m³ in the outdoor air, respectively. Chlorine dioxide and weak acid hypochlorous water aerosols could remove both bacteria and fungi much better than water scrubbing. Contact time of 15 min was sufficient to control both bacteria and fungi to comply with the official air quality standards. User density and carbon dioxide deteriorated both bacteria and fungi disinfection performance whereas temperature was only statistically significant on fungi disinfection. Other factors including relative humidity, airflow velocity, and particulate matters did not have any statistically significant effect on microbial inactivation. Apart from bioaerosol disinfection, inactivation of microorganisms on surfaces of sports equipment was also conducted using chlorine dioxide, zinc oxide, weak acid hypochlorous water, and commercial disinfectant. The surfaces of bicycle handle, dumbbell, and sit-up bench were found to be contaminated with bacteria. Overall bacterial load was 390 to 3720 CFU/cm² with Escherichia coli specifically 550 to 1080 CFU/cm². Chlorine dioxide and zinc oxide were noticeably better than weak acid hypochlorous water and commercial disinfectant in terms of bacteria inactivation whereas all tested disinfectants had comparable effectiveness on E. coli disinfection. Targeted microorganisms on the sports equipment surface were sufficiently inactivated within 2 min after the application of disinfectant.
اظهر المزيد [+] اقل [-]Assessing the microbiological contamination along with environmental factors of old books in the 1490-founded Bistrița Monastery, Romania
2021
Glevitzky, Mirel | Aleya, Lotfi | Vică, Mihaela Laura | Dumitrel, Gabriela-Alina | Avram, Mariana | Tit, Delia Mirela | Popa, Maria | Popa, Viorel-Cristian | Behl, Tapan | Bungau, Simona
Microbial contamination and damaging effects due to environmental factors (temperature, humidity) of old books is an extremely important issue in the heritage preserving field, being a great threat to this unique cultural and literary treasure. This paper analysed the indoor environmental conditions, the microbiological characteristics of the air and the condition itself of 27 clerical books (from eighteenth to nineteenth centuries), randomly chosen from the library of Bistrița Monastery, Romania. The analysis revealed that most of the books were contaminated and damaged by moulds and yeasts. The statistical analysis (chi-square test) shows that the incidence of mould species was not coincidental. The most common isolated fungi discovered on old books were Penicillium spp. (40.7%), Cladosporium spp. (33.3%) and Fusarium spp. (29.6%). Fungal contamination was observed in 17 books. Microbiota air tests have shown possible contamination by air flow. Often, the measured temperature/humidity values are not in line with the requirements of the legislation in force, especially during the cold seasons, the average minimum temperature varying from 3 to 6 °C to an average maximum temperature of 22–25 °C; the values of relative humidity were between 27 and 77%. In terms of storage conditions, the recorded values of temperature and humidity are extremely harmful to the stored documents. Therefore, these indoor environmental conditions have to be improved, in order to reduce/eliminate potential sources of fungal contamination and to achieve optimal environmental preserving conditions.
اظهر المزيد [+] اقل [-]Bibliometric analysis of European publications between 2001 and 2016 on concentrations of selected elements in mushrooms
2020
Świsłowski, Paweł | Dołhańczuk-Śródka, Agnieszka | Rajfur, Małgorzata
This article presents a bibliometric study of 200 European publications released between 2001 and 2016, about the contamination of mushrooms by selected elements. The analysis includes figures on the type of analyte, its concentration, the species of fungi, and its country of origin. In the literature review, 492 species of mushrooms (wild-growing and cultured) found in 26 European countries and their concentration of 74 associated elements were analysed. The papers, which dealt mainly with the heavy metal (Cd, Cu, Fe, Pb, and Zn) concentrations of mushrooms, primarily came from Turkey, Poland, Spain, and the Czech Republic. More than 50% of the publications provided data about edible mushrooms. The results of the bibliometric analysis showed that over the 16 years, European research on fungal contamination by selected analytes has not lessened in popularity and is ongoing. Many of the studies underlined the need to assess the risk to human health arising from the consumption of contaminated mushrooms taken from various habitats. These results were the effect of, among other things, the strong interest in studies carried out on edible species, in which concentrations of mainly heavy metals that are dangerous to health and are marked were indicated (Cd, Pb, and Hg).
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