Bioaerosols of subterraneotherapy chambers at salt mine health resort

Abstract

Nowadays, an inhalation of naturally generated aerosols has again become a widely practiced method of balneological treatment of various respiratory diseases. The aim of this study was to characterize the microbial aerosol of subterraneotherapy chambers at the Bochnia Salt Mine Health Resort in southern Poland. The measurements were carried out using a 6-stage Andersen impactor over a period of 1 year in both indoor (i.e., two subterranean chambers, where curative treatments took place) and outdoor air. The maximum bacterial aerosol concentrations in the chambers reached 11,688 cfu/m3. In such interiors, a high-performance method of microbial contaminant reduction need be introduced, especially when large groups of young patients are medically cured. Respecting fungal aerosol, its average indoor concentration (88 cfu/m3) was significantly lower than outdoor level (538 cfu/m3). It confirms that ventilation system provides efficient barrier against this type of biologically active propagules. Among identified micro-organisms, the most prevalent indoors were Gram-positive cocci, which constituted up to 80 % of airborne microflora. As highly adapted to the diverse environments of its human host (skin, respiratory tract), they can be easily released in high quantities into the air. The number of people introduced into such subterranean chambers should be in some way limited. The analysis of microclimate parameters revealed that temperature and relative humidity influenced significantly the level of bacterial aerosol only. Hence, a constant control of these parameters should be scrupulously superintended at this type of subterranean premises.

Bioaerosol of salt chambers in the ‘Wieliczka’ Salt Mine, Poland

“…Although the bacteria and fungal spore concentration has been measured before in 'Wieliczka' Salt Mine (Obtułowicz et al 2002) and in Bochnia Salt Mine (Frączek et al 2013), the novelty of a current study was to analyse the other biological components, existing in the underground, like natural allergens (originated from animals: cuts and house dust mites) and pollen grains. Pollen occurrence in the salt chambers and outdoor has been compared, to estimate how significant is the difference between both environments.…”

“…At the time of measurement (June-August), only single pollen grains were recorded (Obtułowicz 2002). The comparative studies in the 'Wieliczka' Salt Mine and in the Bochnia Salt Mine were performed by Frączek et al (2013) in 2008 (January-December) and by Gębarowska et al (2018), twice in December 2015 (simultaneous measurements in 'Wieliczka' Salt Mine and in the 'Polkowice-Sieroszowice' Salt Mine).…”

The role of open-air inhalatoria in the air quality improvement in spa towns

“…The vast majority of the air samples from Inowrocław also proved to be uncontaminated. The re sults obtained in Bochnia and Szczawnica [30,31] indicate a low number of moulds also in outdoor environment. Most importantly, the number of moulds in the contami nated samples never exceeded 10 000 CFU×m -3 (high contamination, threatening for the environment).…”

“…Furthermore, apart from Cl -and Na + ions saline aerosol contains F + , Br + , J + and B + ions, which considerably enhance its bacte ricidal properties [28]. The research conducted in subter raneotherapy chambers in Bochnia and Wieliczka [29,30] and inhalation chamber in Szczawnica [31] have con firmed the role of saline aerosol in improving air quality.…”

“…Average numbers of the main microbial groups (mesophilic bacteria and moulds) were lower in Ciechocinek than they were in Inowrocław. Also in other typical spa town, a low air pollution with bio aerosol is usually recorded [30,31]. Fang et al [33] have revealed that microbiological air contamination correlates with the population density and economic activity, and is therefore higher in urban than in rural areas [34].…”