Uncontrolled Post-Industrial Landfill-Source of Metals, Potential Toxic Compounds, Dust, and Pathogens in Environment-A Case Study.

The aim of this case study was the evaluation of the selected metals' concentration, potential toxic compound identification, cytotoxicity analysis, estimation of the airborne dust concentration, biodiversity, and number of microorganisms in the environment (leachate, soil, air) of the biggest uncontrolled post-industrial landfills in Poland. Based on the results obtained, preliminary solutions for the future management of post-industrial objects that have become an uncontrolled landfill were indicated. In the air, the PM1 fraction dominated, constituting 78.1-98.2% of the particulate matter. Bacterial counts were in the ranges of 9.33 × 101-3.21 × 103 CFU m-3 (air), 1.87 × 105-2.30 × 106 CFU mL-1 (leachates), and 8.33 × 104-2.69 × 106 CFU g-1 (soil). In the air, the predominant bacteria were Cellulosimicrobium and Stenotrophomonas. The predominant fungi were Mycosphaerella, Cladosporium, and Chalastospora. The main bacteria in the leachates and soils were Acinetobacter, Mortierella, Proteiniclasticum, Caloramator, and Shewanella. The main fungi in the leachates and soils were Lindtneria. Elevated concentrations of Pb, Zn, and Hg were detected. The soil showed the most pronounced cytotoxic potential, with rates of 36.55%, 63.08%, and 100% for the A-549, Caco-2, and A-549 cell lines. Nine compounds were identified which may be responsible for this cytotoxic effect, including 2,4,8-trimethylquinoline, benzo(f)quinoline, and 1-(m-tolyl)isoquinoline. The microbiome included bacteria and fungi potentially metabolizing toxic compounds and pathogenic species.

The efficiency of nuisance relief by filtering facepiece respirators used by workers exposed to agricultural odours.

BACKGROUND: The study aimed to evaluate the effectiveness of filtering facepiece respirators (FFRs) in reducing odour nuisances in agricultural work environment. Additionally, an assessment was conducted on the microbiological contamination of FFRs and the functionality of Time4Mask application in enhancing workplace safety. MATERIAL AND METHODS: Two types of FFRs were used for the study: with absorbing properties and reference ones. The research was carried out in 6 livestock rooms during a 1-week period in early spring (February-March 2021) on a farm in central Poland. The microclimate conditions (thermoanemometer), and particulate matter concentrations (laser photometer) were assessed. Additionally, the odour content in the studied rooms and the breathing zone of FFR users (gas chromatography with mass spectrometry) were evaluated. The number of microorganisms on the respirators was determined (cultivation method), followed by their identification (biochemical tests, taxonomic keys). Breakthrough curves were determined for both FFR types to assess absorption capabilities. RESULTS: The average temperature in the livestock rooms was about 13°C, relative humidity - 53%, air flow velocity - 0.21 m/s, and particulate matter concentration - 0.216 mg/m3. A significant variety of odorants was found in the environment and the breathing zone under the FFRs. Bacterial counts ranged between 2.4 × 101 and 2.6 × 102 CFU/cm2, fungi between 3.2 × 100 and 5.4 × 101 CFU/cm2, xerophilic fungi from 4.4 × 100 to 4.0 × 101 CFU/cm2, mannitol-positive staphylococci between 1.6 × 101 and 1.0 × 102 CFU/cm2, and haemolytic staphylococci from 2.2 × 101 to 4.5 × 101 CFU/cm2, depending on the respirator type. Respirators were colonized by bacteria from the genera: Bacillus, Staphylococcus, actinobacteria Streptomyces sp., and fungi: Candida, Absidia, Aspergillus, Mucor, and Penicillium. Respirators with absorbing properties had over 8-times longer breakthrough time than reference ones. CONCLUSIONS: Respirators with activated carbon effectively improved work comfort when exposed to odours. Due to growth of microorganisms in the respirator materials, periodic replacement is necessary. It is crucial to provide workers with information about the safe-use time of respirators, considering environmental conditions. This is achievable using modern IT tools like Time4Mask application. Med Pr Work Health Saf. 2023;76(5):363-75.

Markers of Chemical and Microbiological Contamination of the Air in the Sport Centers.

This study aimed to assess the markers of chemical and microbiological contamination of the air at sport centers (e.g., the fitness center in Poland) including the determination of particulate matter, CO2, formaldehyde (DustTrak™ DRX Aerosol Monitor; Multi-functional Air Quality Detector), volatile organic compound (VOC) concentration (headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry), the number of microorganisms in the air (culture methods), and microbial biodiversity (high-throughput sequencing on the Illumina platform). Additionally the number of microorganisms and the presence of SARS-CoV-2 (PCR) on the surfaces was determined. Total particle concentration varied between 0.0445 mg m-3 and 0.0841 mg m-3 with the dominance (99.65-99.99%) of the PM2.5 fraction. The CO2 concentration ranged from 800 ppm to 2198 ppm, while the formaldehyde concentration was from 0.005 mg/m3 to 0.049 mg m-3. A total of 84 VOCs were identified in the air collected from the gym. Phenol, D-limonene, toluene, and 2-ethyl-1-hexanol dominated in the air at the tested facilities. The average daily number of bacteria was 7.17 × 102 CFU m-3-1.68 × 103 CFU m-3, while the number of fungi was 3.03 × 103 CFU m-3-7.34 × 103 CFU m-3. In total, 422 genera of bacteria and 408 genera of fungi representing 21 and 11 phyla, respectively, were detected in the gym. The most abundant bacteria and fungi (>1%) that belonged to the second and third groups of health hazards were: Escherichia-Shigella, Corynebacterium, Bacillus, Staphylococcus, Cladosporium, Aspergillus, and Penicillium. In addition, other species that may be allergenic (Epicoccum) or infectious (Acinetobacter, Sphingomonas, Sporobolomyces) were present in the air. Moreover, the SARS-CoV-2 virus was detected on surfaces in the gym. The monitoring proposal for the assessment of the air quality at a sport center includes the following markers: total particle concentration with the PM2.5 fraction, CO2 concentration, VOCs (phenol, toluene, and 2-ethyl-1-hexanol), and the number of bacteria and fungi.

Biological and chemical contamination of illegal, uncontrolled refuse storage areas in Poland.

This study focused on assessing the microbiological and chemical contamination of air, soil and leachate in uncontrolled refuse storage areas in central Poland. The research included an analysis of the number of microorganisms (culture method), endotoxin concentration (gas chromatography-mass spectrometry), heavy metals level (atomic absorption spectrometry), elemental characteristics (elemental analyser), cytotoxicity assessment against A-549 (human lung) and Caco-2 (human colon adenocarcinoma) cell lines (PrestoBlue™ test) and toxic compound identification (ultra-high-performance liquid chromatography-quadrupole time-of-flight ultrahigh-resolution mass spectrometry). Microbial contamination differed depending on the dump and the group of tested microorganisms. The number of bacteria was: 4.3 × 102 - 1.8 × 103 CFU m-3 (air); 1.1 × 103 - 1.2 × 106 CFU mL-1 (leachate); 1.0 × 106 - 3.9 × 106 CFU g-1 (soil). Respectively, for air and soil the number of fungi was: 2.2 × 102 - 4.6 × 102 CFU m-3; 1.8 × 102 - 3.9 × 103 CFU g-1. Metal levels (Fe, Mn, Pb, Zn, Al, Hg, Cd, Cu, Cr) were higher than in the control sample; however, the average concentrations did not exceed the permissible standards. The cytotoxicity of soil and leachate samples depended on the dump, sample and cell line tested. The leachates were more cytotoxic than soil extracts. Compounds belonging to pesticides, surfactants and biocides, chemicals and/or polymer degradation products, medicinal drugs and insect repellents were found. The detection of potential pathogens in the air, soil and leachate, the presence of toxic compounds and the confirmation of the cytotoxic effect of leachate and soil on human cell lines justify the need for further research on the risks posed by illegal dumps. These studies should aim at developing a unified assessment method and a method to minimise the risk of contaminants spreading in the environment, including harmful biological agents.

Assessment of Dust, Chemical, Microbiological Pollutions and Microclimatic Parameters of Indoor Air in Sports Facilities.

The aim of this study was to analyse the quality of indoor air in sport facilities in one of the sport centres in Poland with respect to microclimatic parameters (temperature, humidity, and air flow velocity), particulate matter concentrations (PM10, PM4, PM2.5, and PM1), gas concentrations (oxygen, ozone, hydrogen sulphide, sulphur dioxide, volatile organic compounds, and benzopyrene), and microbial contamination (the total number of bacteria, specifically staphylococci, including Staphylococcus aureus, haemolytic bacteria, Enterobacteriaceae, Pseudomonas fluorescens, actinomycetes, and the total number of fungi and xerophilic fungi). Measurements were made three times in May 2022 at 28 sampling points in 5 different sporting areas (the climbing wall, swimming pool, swimming pool changing room, and basketball and badminton courts) depending on the time of day (morning or afternoon) and on the outside building. The obtained results were compared with the standards for air quality in sports facilities. The air temperature (21−31 °C) was at the upper limit of thermal comfort, while the air humidity (RH < 40%) in the sports halls in most of the locations was below demanded values. The values for dust pollution in all rooms, except the swimming pool, exceeded the permissible limits, especially in the afternoons. Climatic conditions correlated with a high concentration of dust in the indoor air. Particulate matter concentrations of all fractions exceeded the WHO guidelines in all researched premises; the largest exceedances of standards occurred for PM2.5 (five-fold) and for PM10 (two-fold). There were no exceedances of gaseous pollutant concentrations in the air, except for benzopyrene, which resulted from the influence of the outside air. The total number of bacteria (5.1 × 101−2.0 × 104 CFU m−3) and fungi (3.0 × 101−3.75 × 102 CFU m−3) was exceeded in the changing room and the climbing wall hall. An increased number of staphylococci in the afternoon was associated with a large number of people training. The increased concentration of xerophilic fungi in the air correlated with the high dust content and low air humidity. Along with the increase in the number of users in the afternoon and their activities, the concentration of dust (several times) and microorganisms (1−2 log) in the air increased by several times and 1−2 log, respectively. The present study indicates which air quality parameters should be monitored and provides guidelines on how to increase the comfort of those who practice sports and work in sports facilities.

Evaluation of the Tooth Surface after Irradiation with Diode Laser Applied for Removal of Dental Microorganisms from Teeth of Patients with Gingivitis, Using X-ray Photoelectron (XPS) and Optical Profilometry (OP).

Gingivitis is accompanied by microorganisms, including pathogens, which must be eliminated to speed up the treatment of inflammation. Laser irradiation may be one of the safe methods for reducing tissue contamination on the tooth surface. The aim of the study was the assessment of the tooth surface in patients with gingivitis after the use of a diode laser to eliminate microorganisms living there. In the first stage of the research, microorganisms were isolated (Candida albicans, C. guilliermondii, Escherichia coli, Haemophilus parainfluenzae, Klebsiella oxytoca, Neisseria subflava, Rothia dentocariosa, Rothia mucilaginosa, Streptococcus pneumoniae) from three patients with gingivitis, their identification confirmed using the MALDI-TOF MS technique (matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry). Then, the irradiation process with a diode laser was optimized to a wavelength of 810 nm ± 10 nm in five variants to reduce microorganisms on the tooth. The tooth surface was analyzed by X-ray photoelectron spectroscopy (XPS) and optical profilometry (OP) before and after irradiation. 103 to 106 CFU were detected on a 0.4 cm2 tooth area. Nine types of bacteria and two types of fungi dominated among the microorganisms. The laser at the most effective biocidal dose of 25 W/15.000 Hz/10 µs, average = 3.84 W, with three uses after 15 s, increased the reduction of fungi from 57.97% to 93.80%, and bacteria from 30.67% to 100%. This dose also caused a decrease in the degree of oxidation and in the effect of smoothing on the treated surfaces.

Antagonistic Activity of Potentially Probiotic Lactic Acid Bacteria against Honeybee (Apis mellifera L.) Pathogens.

Lactic acid bacteria (LAB) are an essential part of the microbiota of the digestive tract of honeybees (Apis mellifera L.). Antagonistic activity of 103 LAB strains (isolates from different environments) against 21 honeybee pathogens/opportunistic pathogens (with agar slab method) was screened. The growth of Paenibacillus genus was inhibited to the most extent. The highest antagonistic activity was demonstrated by Lacticaseibacillus casei 12AN, while the lowest by Apilactobacillus kunkeei DSM 12361, a species naturally inhabiting the honeybee gut. LAB isolated from the honeybee environment demonstrated stronger antagonism against pathogens than collection strains. The antagonistic activity of cell-free supernatants (CFSs) from 24 LAB strains against 7 honeybee pathogens was additionally assessed at physiological pH with the microtitration method. The same was determined for selected CFSs at neutralized pH. CFSs with physiological pH showed significantly stronger antibacterial activity than CFSs with neutralized pH. The results confirmed that the mechanism of antimicrobial activity of LAB is acidification of the environment. The obtained results may, in the future, contribute to a better understanding of the antagonistic properties of LAB and the construction of a probiotic preparation to increase the viability of honeybee colonies.

Assessment of Physicochemical, Microbiological and Toxicological Hazards at an Illegal Landfill in Central Poland.

This study aimed to assess the physicochemical, microbiological and toxicological hazards at an illegal landfill in central Poland. The research included the analysis of airborne dust (laser photometer), the number of microorganisms in the air, soil and leachate (culture method) and the microbial diversity in the landfill environment (high-throughput sequencing on the Illumina Miseq); the cytotoxicity (PrestoBlue) and genotoxicity (alkaline comet assay) of soil and leachate were tested. Moreover, an analysis of UHPLC-Q-ToF-UHRMS (ultra-high-performance liquid chromatography-quadrupole-time-of-flight ultrahigh-resolution mass spectrometry) was performed to determine the toxic compounds and microbial metabolites. The PM1 dust fraction constituted 99.89% and 99.99% of total dust and exceeded the threshold of 0.025 mg m-3 at the tested locations. In the air, the total number of bacteria was 9.33 × 101-1.11 × 103 CFU m-3, while fungi ranged from 1.17 × 102 to 4.73 × 102 CFU m-3. Psychrophilic bacteria were detected in the largest number in leachates (3.3 × 104 to 2.69 × 106 CFU mL-1) and in soil samples (8.53 × 105 to 1.28 × 106 CFU g-1). Bacteria belonging to Proteobacteria (42-64.7%), Bacteroidetes (4.2-23.7%), Actinobacteria (3.4-19.8%) and Firmicutes (0.7-6.3%) dominated. In the case of fungi, Basidiomycota (23.3-27.7%), Ascomycota (5.6-46.3%) and Mortierellomycota (3.1%) have the highest abundance. Bacteria (Bacillus, Clostridium, Cellulosimicrobium, Escherichia, Pseudomonas) and fungi (Microascus, Chrysosporium, Candida, Malassezia, Aspergillus, Alternaria, Fusarium, Stachybotrys, Cladosporium, Didymella) that are potentially hazardous to human health were detected in samples collected from the landfill. Tested leachates and soils were characterised by varied cyto/genotoxins. Common pesticides (carbamazepine, prometryn, terbutryn, permethrin, carbanilide, pyrethrin, carbaryl and prallethrin), quaternary ammonium compounds (benzalkonium chlorides), chemicals and/or polymer degradation products (melamine, triphenylphosphate, diphenylphtalate, insect repellent diethyltoluamide, and drugs (ketoprofen)) were found in soil and leachate samples. It has been proven that the tested landfill is the source of the emission of particulate matter; microorganisms (including potential pathogens) and cyto/genotoxic compounds.

Microbiological and toxicological hazard assessment in a waste sorting plant and proper respiratory protection.

Even though biological hazards in the work environments related to waste management were the subject of many scientific works, the knowledge of the topic is not extensive. This study aimed to conduct a comprehensive assessment of microbiological and toxicological hazards at the workstations in a waste sorting plant and develop guidelines for selecting filtering respiratory protective devices that would consider specific workplace conditions. The research included the assessment of quantity (culture method), diversity (high-throughput sequencing), and metabolites (endotoxin - gas chromatography-mass spectrometry; secondary metabolites - liquid chromatography tandem-mass spectrometry) of microorganisms occurring in the air and settled dust. Moreover, cytotoxicity of settled dust against a human epithelial lung cell line was determined with an MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. The research was performed in a waste sorting plant (Poland; 240,000 tons waste/year) at six workstations: two feeders, two pre-sorting cabins, secondary raw material press and organic fraction waste feeder for composting. The total dust concentration at tested workstations varied from 0.128 mg m-3 to 5.443 mg m-3. The number of microorganisms was between 9.23 × 104 CFU m-3 and 1.38 × 105 CFU m-3 for bacteria and between 1.43 × 105 CFU m-3 and 1.65 × 105 CFU m-3 for fungi, which suggests high microbial contamination of the sorting facility. The numbers of microorganisms in the air correlated very strongly (R2 from 0.70 to 0.94) with those observed in settled dust. Microorganisms representing Group 2 biological agents (acc. to Directive, 2000/54/EC), including Corynebacterium spp., Pseudomonas aeruginosa, Staphylococcus aureus, and others potentially hazardous to human health, were identified. The endotoxins concentration in settled dust ranged from 0.013 nmol LPS mg-1 to 0.048 nmol LPS mg-1. Seventeen (air) and 91 (settled dust) secondary metabolites characteristic, e.g., for moulds, bacteria, lichens, and plants were identified. All dust samples were cytotoxic (IC50 values of 8.66 and 56.15 mg ml-1 after 72 h). A flowchart of respiratory protective devices selection for biological hazards at the workstations in the waste sorting plant was proposed based on the completed tests to help determine the right type and use duration of the equipment.

Microbiological and Toxicological Hazards in Sewage Treatment Plant Bioaerosol and Dust.

Despite the awareness that work in the sewage treatment plant is associated with biological hazards, they have not been fully recognised so far. The research aims to comprehensively evaluate microbiological and toxicological hazards in the air and settled dust in workstations in a sewage treatment plant. The number of microorganisms in the air and settled dust was determined using the culture method and the diversity was evaluated using high-throughput sequencing. Endotoxin concentration was assessed with GC-MS (gas chromatography-mass spectrometry) while secondary metabolites with LC-MS/MS (liquid chromatography coupled to tandem mass spectrometry). Moreover, cytotoxicity of settled dust against a human lung epithelial lung cell line was determined with the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and UHPLC-Q-ToF-UHRMS (ultra-high-performance liquid chromatography-quadrupole time-of-flight ultrahigh-resolution mass spectrometry) analysis was performed to determine the source of cytotoxicity. The total dust concentration in the sewage treatment plant was low and ranged from 0.030 mg m-3 to 0.044 mg m-3. The highest microbiological contamination was observed in sludge thickening building and screenings storage. Three secondary metabolites were detected in the air and sixteen in the settled dust. They were dominated by compounds typical of lichen and plants and Aspergillus, Penicillium and Fusarium genera mould. The settled dust from the sludge thickening building revealed high cytotoxicity to human lung epithelial cells A-549 (IC50 = 6.98 after 72 h). This effect can be attributed to a biocidal compound-didecyldimethylammonium chloride (DDAC-C10) and seven toxic compounds: 4-hydroxynonenal, carbofuran, cerulenin, diethylphosphate, fenpropimorph, naphthalene and onchidal. The presence of DDAC-C10 and other biocidal substances in the sewage treatment plant environment may bring negative results for biological sewage treatment and the natural environment in the future and contribute to microorganisms' increasing antibiotics resistance. Therefore, the concentration of antibiotics, pesticides and disinfectants in sewage treatment plant workstations should be monitored.

Application of Olfactometry to Assess the Anti-Odor Properties of Filtering Facepiece Respirators Containing Activated Carbon Nonwovens.

Filtering facepiece respirators (FFR) with anti-odor properties are used to reduce odor nuisance occurring both in everyday life and at workplaces. Unfortunately, there are no standardized methods to measure the efficiency of odor reduction of such personal protective devices. This paper aims to determine whether olfactometric-based methods, commonly used in environmental studies, can be employed for this purpose. The proposed procedure is based on the detection of n-butanol by study participants, and it consists of three subsequent stages: (i) defining the individual levels of odor sensitivity of each study participant; (ii) determining THE odor detection level while using FFRs with varying anti-odor properties; and (iii) completing a questionnaire concerning the subjective perceptions of study participants. As a measure of odor reduction efficiency, a coefficient W, defined as a quotient of the degree of odor reduction by the FFR, and the individual odor sensitivity of the subject, was proposed. The experimental results showed the ability of our measure to differentiate the effectiveness of odor reduction of tested FFRs. This indicates that it can be potentially employed as the assessment tool to confirm the effectiveness of such respiratory protective devices as a control measure mitigating the adverse effects of malodors on workers' health, cognition, and behavior.

Silver-109/Silver/Gold Nanoparticle-Enhanced Target Surface-Assisted Laser Desorption/Ionisation Mass Spectrometry-The New Methods for an Assessment of Mycotoxin Concentration on Building Materials.

This study aimed to detect and quantify mycotoxins on building materials using innovative laser mass spectroscopy methods-silver-109/silver/gold nanoparticle-enhanced target surface-assisted laser desorption/ionisation mass spectrometry (109AgNPs, AgNPs and AuNPs SALDI). Results from SALDI-type methods were also compared with commonly used matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. Standards of seven moulds mycotoxin in a final concentration of 100 µg/mL for patulin, citrinin, 3-nitropropionic acid, alternariol and 20 µg/mL for sterigmatocystin, cyclopiazonic acid, roquefortine C in the mixture were tested in pure solutions and after extraction from the plasterboards. Among the studied SALDI-type method, the lowest detection limits and the highest signal intensity of the mycotoxins tested were obtained with the use of 109AgNPs SALDI MS. The 109AgNPs method may be considered as an alternative to the currently most frequently used method MALDI MS and also liquid chromatography tandem mass spectrometry LC-MS/MS for mycotoxin determination. Future studies should attempt to use these methods for mass spectrometry imaging (MSI) to evaluate spatial distribution and depth of mycotoxin penetration into building materials.

Viscoelastic Polyurethane Foams with Reduced Flammability and Cytotoxicity.

Consistent and proper use of respiratory protective devices (RPD) is one of the essential actions that can be taken to reduce the risk of exposure to airborne hazards, i.e., biological and nonbiological aerosols, vapours, and gases. Proper fit of the facepiece and comfort properties of RPDs play a crucial role in effective protection and acceptance of RPDs by workers. The objective of the present paper was to develop viscoelastic polyurethane foams for use in RPD seals characterised by proper elasticity, allowing for the enhancement of the device fit to the face and the capability of removing moisture from the skin in order to improve the comfort of RPD use. Moreover, it was pivotal to ensure the non-flammability of the foams, as well as a simultaneous reduction in their cytotoxicity. The obtained foams were characterised using scanning electron microscopy, infrared spectroscopy, thermogravimetry, and differential scanning calorimetry. Measurements also involved gel fraction, apparent density, compression set, rebound resilience, wettability, flammability, and cytotoxicity. The results are discussed in the context of the impact of modifications to the foam formulation (i.e., flame-retardant type and content) on the desired foam properties. The test results set directions for future works aimed to develop viscoelastic polyurethane foams that could be applied in the design of respiratory protective devices.

Laser Ablation Remote-Electrospray Ionisation Mass Spectrometry (LARESI MSI) Imaging-New Method for Detection and Spatial Localization of Metabolites and Mycotoxins Produced by Moulds.

To date, no method has been developed to assess the distribution of mycotoxins on the surface of grains, or other plant material, and the depth of their penetration into the interior. The Infrared (IR) Laser Ablation-Remote-Electrospray Ionization (LARESI) platform coupled to a tandem mass spectrometer (MS/MS), measuring in selected reaction monitoring (SRM) mode, was employed for the targeted imaging of selected metabolites of Aspergillus fumigatus, including mycotoxins in biological objects for the first time. This methodology allowed for the localisation of grain metabolites and fungal metabolites of grain infected by this mould. The distribution of metabolites in spelt grain was differentiated: fumigaclavine C, fumitremorgin C, and fumiquinazoline D were located mainly in the embryo, brevianamide F in the seed coat, and fumagillin in the endosperm. The LARESI mass spectrometry imaging method can be used in the future for the metabolomic analysis of mould metabolites in various plants and agricultural products.

Cotton Terry Textiles with Photo- and Bio-Activity in a Model Study and Real Conditions.

The aim of the study was to assess the photocatalytic (decompose staining particles, K/S values, the color differences, CIE L*a*b* color) and antimicrobial properties of textiles modified with TiO2 and ZnO nanoparticles (NPs) confirmed by X-ray diffraction, dynamic light scattering, SEM-EDX) in visible light conditions. The antimicrobial effectiveness of modified textiles under model conditions has been reported against 5 microorganisms: Staphylococcus aureus, Escherichia coli, Bacillus subtilis, Candida albicans, Aspergillus niger (AATCC Test Method 100-2004). In real conditions in bathrooms, significant biostatic activity was shown on the surface of the modified towels. The number of microorganisms decreased by 1-5 log to the level of 0-5 CFU/cm2 in the case of bacteria: Enterobacteriaceae, Enterococcus, the coli group and E. coli, Pseudomonas. Statistically significant reduction of the total number of bacteria and fungi (by 1 log), and the concentration of gases (NO2, CO2, CO) in the air of bathrooms was determined. The removal or reduction of volatile organic compounds (VOCs) concentration (SPME-GC-MS analysis) in the air above the modified towels has also been determined. It was found that the lighting type (natural, artificial), time (1.5 and 7 h/day), air humidity (RH = 36-67%) and light intensity (81-167 lux) are important for the efficiency of photocatalysis. Textile materials modified with TiO2 and ZnO NPs can be used as self-cleaning towels. They can also help purify air from microorganisms, VOCs and undesirable gases.

Beeswax-Modified Textiles: Method of Preparation and Assessment of Antimicrobial Properties.

In this work, beeswax was used for the first time for finishing polyester/Cotton/Viscose blend fabric and polyester fabric. The aims of the study were: (1) to characterize the composition of beeswax (using Gas Chromatography Mass Spectrometry, GC-MS and 109AgNPET laser desorption/ionization mass spectrometry (LDI MS); (2) to develop a laboratory method for applying beeswax; (3) to assess the antimicrobial activity of beeswax fabrics against bacteria and fungi (AATCC 100-2004 test); and (4) to assess the properties of textiles modified by beeswax. Beeswax was composed of fatty acids, monoacyl esters, glyceride esters and more complex lipids. The bioactivity of modified fabrics was from -0.09 to 1.55. The highest biocidal activity (>1) was obtained for both fabrics against A. niger mold. The beeswax modification process neither affected the morphological structure of the fibers (the wax evenly covered the surface of the fibers) nor their color. The only statistically significant changes observed were in the mechanical properties of the fabrics. The results obtained indicate that modification of fabrics with beeswax may endow them with biocidal properties against molds, which has practical applications, for example, for the prevention of skin mycoses in health and social care facilities.

Factors Influencing Microbiological Biodiversity of Human Foot Skin.

The aim of the study was to analyze the microbiological biodiversity of human foot skin with respect to factors such as age, gender, frequency of foot washing and physical activity, and to select indicator species to be considered when designing textile materials with antimicrobial properties used for sock and insole production. The experiment was carried out on a group of 40 people. The number of microorganisms was determined using culture-dependent methods. Biodiversity was determined using culture followed by genetic identification based on 16S rRNA gene sequencing (bacteria), ITS region (fungi), or using Illumina next-generation sequencing (in a group of eight selected individuals). The total bacterial number on women's feet was on average 1.0 × 106 CFU/cm2, and was not statistically significantly different than that of men's feet (mean 1.2 × 105 CFU/cm2). The number of bacteria, in most cases, decreased with age and with increased frequency of physical activity. The number of bacteria increased with diminishing feet-washing frequency; however, statistically significant differences were found between groups. The number of fungi was not significantly different amongst groups. Bacteria belonging to the phyla Firmicutes, Proteobacteria and Actinobacteria constituted the main microorganisms of the foot skin. Ascomycota and Basidiomycota predominated amongst the fungi. The presence of specific species varied in groups depending on the factors mentioned above. Two of the species identified were classified as pathogens (Neisseria flavescens and Aspergillus fumigatus). These findings suggest that it is necessary to extend the list of microorganisms tested on textiles with respect to hygienic properties.

Application of Biocides and Super-Absorbing Polymers to Enhance the Efficiency of Filtering Materials.

Studies on the functionalization of materials used for the construction of filtering facepiece respirators (FFRs) relate to endowing fibers with biocidal properties. There is also a real need for reducing moisture content accumulating in such materials during FFR use, as it would lead to decreased microorganism survival. Thus, in our study, we propose the use of superabsorbent polymers (SAPs), together with a biocidal agent (biohalloysite), as additives in the manufacturing of polypropylene/polyester (PP/PET) multifunctional filtering material (MFM). The aim of this study was to evaluate the MFM for stability of the modifier's attachment to the polymer matrix, the degree of survival of microorganisms on the nonwoven, and its microorganism filtration efficiency. Scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy were used to test the stability of the modifier's attachment. The filtration efficiency was determined under conditions of dynamic aerosol flow of S. aureus bacteria. The survival rates (N%) of the following microorganisms were assessed: Escherichia coli and Staphylococcus aureus bacteria, Candida albicans yeast, and Aspergillus niger mold using the AATCC 100-2004 method. FTIR spectrum analysis confirmed the pre-established composition of MFM. The loss of the active substance from MFM in simulated conditions of use did not exceed 0.02%, which validated the stability of the modifier's attachment to the PP/PET fiber structure. SEM image analysis verified the uniformity of the MFM structure. Lower microorganism survival rates were detected for S. aureus, C. albicans, and E. coli on the MFM nonwoven compared to control samples that did not contain the modifiers. However, the MFM did not inhibit A. niger growth. The MFM also showed high filtration efficiency (99.86%) against S. aureus bacteria.

Survival of Microorganisms on Filtering Respiratory Protective Devices Used at Agricultural Facilities.

Bioaerosol is a threat at workplaces, therefore the selection and safe use of filtering facepiece respirators (FFRs) is important in preventive activities. The aim of the study was to assess the survival of microorganisms on materials used for FFRs construction. The parameters for microorganism growth under model conditions were described using the Gompertz equation, model verification was also carried out using FFRs at the farmers' workplaces. We found that the factors determining a high survival of microorganisms were as follows: moisture corresponding to the conditions of use and storage of FFRs at workplaces, the presence of sweat and organic dust; inorganic dust and addition of biocide in nonwovens limited the growth of microorganisms, resulting in a shortening of the stationary growth phase and decreased cell numbers (5-6 log). Dust concentration at workplaces was higher than EU occupational exposure limit values and WHO recommendations for airborne particulate matter. Microbial contaminations of the air (103-104 CFU/m3), settled dust (104-106 CFU/g) and FFRs (105 CFU/4cm2) during the grain harvest were high, the main contamination being bacteria (actinomycetes, Pseudomonas fluorescens) and xerophilic fungi. A high correlation was found between the number of microorganisms and the weight of dust on FFRs (R2 = 0.93-0.96).

Survival of Microorganisms on Nonwovens Used for the Construction of Filtering Facepiece Respirators.

Filtering nonwovens that constitute the base material for filtering facepiece respirators (FFRs) used for the protection of the respiratory system against bioaerosols may, in favourable conditions, promote the development of harmful microorganisms. There are no studies looking at the impact that different types of filtering nonwovens have on microorganism survival, which is an important issue for FFR producers and users. Five commercial filtering nonwovens manufactured using diverse textile technologies (i.e., needle-punching, melt-blown, spun-bonding) with different structural parameters and raw material compositions were used within our research. The survival of microorganisms on filtering nonwovens was determined for E. coli, S. aureus, B. subtilis bacteria; C. albicans yeast and A. niger mould. Samples of nonwovens were collected immediately after inoculum application (at 0 h) and after 4, 8, 24, 48, 72, and 96 h of incubation. The tests were carried out in accordance with the AATCC 100-1998 method. Survival depended strongly on microorganism species. E. coli and S. aureus bacteria grew the most on all nonwovens tested. The structural parameters of the nonwovens tested (mass per unit area and thickness) and contact angle did not significantly affect microorganism survival.