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The aim of this review was to investigate human exposure to relevant indoor air contaminants, predictors affecting the levels, and the means to reduce the harmful exposure in indoor sports facilities. Our study revealed that the contaminants of primary concern are the following: particulate matter in indoor climbing, golf, and horse riding facilities; carbon dioxide and particulate matter in fitness centers, gymnasiums, and sports halls; Staphylococci on gymnasium surfaces; nitrogen dioxide and carbon monoxide in ice hockey arenas; carbon monoxide, nitrogen oxide(s), and particulate matter in motor sports arenas; and disinfection by‐products in indoor chlorinated swimming pools. Means to reduce human exposure to indoor contaminants include the following: adequate mechanical ventilation with filters, suitable cleaning practices, a limited number of occupants in fitness centers and gymnasiums, the use of electric resurfacers instead of the engine powered resurfacers in ice hockey arenas, carefully regulated chlorine and temperature levels in indoor swimming pools, properly ventilated pools, and good personal hygiene. Because of the large number of susceptible people in these facilities, as well as all active people having an increased respiratory rate and airflow velocity, strict air quality requirements in indoor sports facilities should be maintained. [ABSTRACT FROM AUTHOR]

Abstract Background Although it is recognized that ozone causes acute and chronic health effects and that even trace amounts of ozone are potentially deleterious to human health, information about global and local exposures to ozone in different indoor environments is limited. To synthesize the existing knowledge, this review analyzes the magnitude of and the trends in global and local exposure to ozone in schools and offices and the factors controlling the exposures. Methods In conducting the literature review, Web of Science, SCOPUS, Google Scholar, and PubMed were searched using 38 search terms and their combinations to identify manuscripts, reports, and directives published between 1973 and 2018. The search was then extended to the reference lists of relevant articles. Results The calculated median concentration of ozone both in school (8.50 μg/m3) and office (9.04 μg/m3) settings was well below the WHO guideline value of 100 μg/m3 as a maximum 8 h mean concentration. However, a large range of average concentrations of ozone was reported, from 0.8–114 μg/m3 and from 0 to 96.8 μg/m3 for school and office environments, respectively, indicating situations where the WHO values are exceeded. Outdoor ozone penetrating into the indoor environment is the main source of indoor ozone, with median I/O ratios of 0.21 and 0.29 in school and office environments, respectively. The absence of major indoor ozone sources and ozone sinks, including gas-phase reactions and deposition, are the reasons for lower indoor than outdoor ozone concentrations. However, there are indoor sources of ozone that are of significance in certain indoor environments, including printers, photocopiers, and many other devices and appliances designed for indoor use (e.g., air cleaners), that release ozone either intentionally or unintentionally. Due to significantly elevated outdoor ozone concentrations during summer, summer indoor concentrations are typically elevated. In addition, the age of a building and various housing aspects (carpeting, air conditioning, window fans, and window openings) have been significantly associated with indoor ozone levels. Conclusions The existing means for reducing ozone and ozone reaction products in school and office settings are as follows: 1) reduce penetration of outdoor ozone indoors by filtering ozone from the supply air; 2) limit the use of printers, photocopiers, and other devices and appliances that emit ozone indoors; 3) limit gas-phase reactions by limiting the use of materials and products (e.g. cleaning chemicals) the emissions of which react with ozone. Highlights • The potential for ozone formation in the troposphere is increasing. • Ozone is of particular significance in schools and offices. • The median indoor concentration of O 3 was 8.50 μg/m3 and 9.04 μg/m3 in schools and offices, respectively. • Median I/O ratios of O 3 were 0.21 and 0.29 in schools and offices, respectively. • The concentrations of ozone and ozone reaction products must be minimized. [ABSTRACT FROM AUTHOR]

As endotoxin exposure has known effects on human health, it is important to know the generally existing levels of endotoxins as well as their contributing factors. This work reviews current knowledge on the endotoxin loads in settled floor dust, concentrations of endotoxins in indoor air, and different environmental factors potentially affecting endotoxin levels. The literature review consists of peer-reviewed manuscripts located using Google and PubMed, with search terms based on individual words and combinations. References from relevant articles have also been searched. Analysis of the data showed that in residential, school, and office environments, the mean endotoxin loads in settled floor dust varied between 660 and 107,000 EU/m 2 , 2180 and 48,000 EU/m 2 , and 2700 and 12,890 EU/m 2 , respectively. Correspondingly, the mean endotoxin concentrations in indoor air varied between 0.04 and 1610 EU/m 3 in residences, and 0.07 and 9.30 EU/m 3 in schools and offices. There is strong scientific evidence indicating that age of houses (or housing unit year category), cleaning, farm or rural living, flooring materials (the presence of carpets), number of occupants, the presence of dogs or cats indoors, and relative humidity affect endotoxin loads in settled floor dust. The presence of pets (especially dogs) was extremely strongly associated with endotoxin concentrations in indoor air. However, as reviewed articles show inconsistency, additional studies on these and other possible predicting factors are needed. [ABSTRACT FROM AUTHOR]

There is currently a lack of reference values for indoor air fungal concentrations to allow for the interpretation of measurement results in subtropical school settings. Analysis of the results of this work established that, in the majority of properly maintained subtropical school buildings, without any major affecting events such as floods or visible mould or moisture contamination, indoor culturable fungi levels were driven by outdoor concentration. The results also allowed us to benchmark the “baseline range” concentrations for total culturable fungi, Penicillium spp., Cladosporium spp. and Aspergillus spp. in such school settings. The measured concentration of total culturable fungi and three individual fungal genera were estimated using Bayesian hierarchical modelling. Pooling of these estimates provided a predictive distribution for concentrations at an unobserved school. The results indicated that “baseline” indoor concentration levels for indoor total fungi, Penicillium spp., Cladosporium spp. and Aspergillus spp. in such school settings were generally ≤1450, ≤680, ≤480 and ≤90 cfu/m 3 , respectively, and elevated levels would indicate mould damage in building structures. The indoor/outdoor ratio for most classrooms had 95% credible intervals containing 1, indicating that fungi concentrations are generally the same indoors and outdoors at each school. Bayesian fixed effects regression modelling showed that increasing both temperature and humidity resulted in higher levels of fungi concentration. [ABSTRACT FROM AUTHOR]

Elevated levels of fungi in indoor environments have been linked with mould/moisture damage in building structures. However, there is a lack of information about “normal” concentrations and flora as well as guidelines of viable fungi in the school environment in different climatic conditions. We have reviewed existing guidelines for indoor fungi and the current knowledge of the concentrations and flora of viable fungi in different climatic areas, the impact of the local factors on concentrations and flora of viable fungi in school environments. Meta-regression was performed to estimate the average behaviour for each analysis of interest, showing wide variation in the mean concentrations in outdoor and indoor school environments (range: 10 1 –10 3 cfu/m 3 ). These concentrations were significantly higher for both outdoors and indoors in the moderate than in the continental climatic area, showing that the climatic condition was a determinant for the concentrations of airborne viable fungi. The most common fungal species both in the moderate and continental area were Cladosporium spp. and Penicillium spp. The suggested few quantitative guidelines for indoor air viable fungi for school buildings are much lower than for residential areas. This review provides a synthesis, which can be used to guide the interpretation of the fungi measurements results and help to find indications of mould/moisture in school building structures. [ABSTRACT FROM AUTHOR]

Abstract: In January 2011, Brisbane, Australia, experienced a major river flooding event. We aimed to investigate its effects on air quality and assess the role of prompt cleaning activities in reducing the airborne exposure risk. A comprehensive, multi-parameter indoor and outdoor measurement campaign was conducted in 41 residential houses, 2 and 6months after the flood. The median indoor air concentrations of supermicrometer particle number (PN), PM10, fungi and bacteria 2months after the flood were comparable to those previously measured in Brisbane. These were 2.88pcm−3, 15μgm−3, 804cfum−3 and 177cfum−3 for flood-affected houses (AFH), and 2.74pcm−3, 15μgm−3, 547cfum−3 and 167cfum−3 for non-affected houses (NFH), respectively. The I/O (indoor/outdoor) ratios of these pollutants were 1.08, 1.38, 0.74 and 1.76 for AFH and 1.03, 1.32, 0.83 and 2.17 for NFH, respectively. The average of total elements (together with transition metals) in indoor dust was 2296±1328μgm−2 for AFH and 1454±678μgm−2 for NFH, respectively. In general, the differences between AFH and NFH were not statistically significant, implying the absence of a measureable effect on air quality from the flood. We postulate that this was due to the very swift and effective cleaning of the flooded houses by 60,000 volunteers. Among the various cleaning methods, the use of both detergent and bleach was the most efficient at controlling indoor bacteria. All cleaning methods were equally effective for indoor fungi. This study provides quantitative evidence of the significant impact of immediate post-flood cleaning on mitigating the effects of flooding on indoor bioaerosol contamination and other pollutants. [Copyright &y& Elsevier]

Endotoxins can significantly affect the air quality in school environments. However, there is currently no reliable method for the measurement of endotoxins, and there is a lack of reference values for endotoxin concentrations to aid in the interpretation of measurement results in school settings. We benchmarked the "baseline" range of endotoxin concentration in indoor air, together with endotoxin load in floor dust, and evaluated the correlation between endotoxin levels in indoor air and settled dust, as well as the effects of temperature and humidity on these levels in subtropical school settings. Bayesian hierarchical modeling indicated that the concentration in indoor air and the load in floor dust were generally (<95th percentile) <13 EU/m³ and <24,570 EU/m², respectively. Exceeding these levels would indicate abnormal sources of endotoxins in the school environment and the need for further investigation. Metaregression indicated no relationship between endotoxin concentration and load, which points to the necessity for measuring endotoxin levels in both the air and settled dust. Temperature increases were associated with lower concentrations in indoor air and higher loads in floor dust. Higher levels of humidity may be associated with lower airborne endotoxin concentrations. [ABSTRACT FROM AUTHOR]

The article focuse on a study concerning airborne particle concentrations that can be used as quality indicators of indoor office environments. It notes that previous lack of reference data has thwarted the use of particle measurements in office environments. It provides a description of the concentrations of airborne particles in more than a hundred Finnish office buildings with suspected indoor air problems. Materials and methods used in the study are presented.

The fungi and bacterial levels of the indoor air environments of 77 office buildings were measured in winter and a comparison was made between the buildings with microbe sources in their structures and those without such sources. Penicillium, yeasts, Cladosporium and non-sporing isolates were the commonest fungi detected in the indoor air and in settled dust, in both the mould-damaged and control buildings. Aspergillus ochraceus, Aspergillus glaucus and Stachybotrys chartarium were found only in environmental samples from the mould-damaged buildings. Some other fungi, with growth requiring of water activity, a w, above 0.85, occurred in both the reference and mould-damaged buildings, but such fungi were commoner in the latter type of buildings. The airborne concentrations of Penicillium, Aspergillus versicolor and yeasts were the best indicators of mould damage in the buildings studied. Penicillium species and A. versicolor were also the most abundant fungi in the material samples. This study showed that the fungi concentrations were very low (2–45cfum−3 90% of the concentrations being <15cfum−3) in the indoor air of the normal office buildings. Although the concentration range of airborne fungi was wider for the mould-damaged buildings (2–2470cfum−3), only about 20% of the samples exceeded 100cfum−3. The concentrations of airborne bacteria ranged from 12 to 540cfum−3 in the control buildings and from 14 to 1550cfum−3 in the mould-damaged buildings. A statistical analysis of the results indicated that bacteria levels are generally <600cfum−3 in office buildings in winter and fungi levels are <50cfum−3. These normal levels are applicable to subarctic climates for urban, modern office buildings when measurements are made using a six-stage impactor. These levels should not be used in evaluations of health risks, but elevated levels may indicate the presence of abnormal microbe sources in indoor air and a need for additional environmental investigations. [Copyright &y& Elsevier]

Although nitrogen dioxide (NO 2) is one of the most common air pollutants encountered indoors, and extensive literature has examined the link between NO 2 exposure and duration causing adverse respiratory effects in susceptible populations, information about global and local exposure to NO 2 in different indoor environments is limited. To synthesize the existing knowledge, this review analyzes the magnitude of and the trends in global and local exposure to NO 2 in schools and offices, and the factors that control exposure. For the literature review, Web of Science, SCOPUS, Google Scholar, and PubMed were searched using 42 search terms and their combinations to identify manuscripts, reports, and directives published between 1971 and 2019. The search was then extended to the reference lists of relevant articles. The calculated median, as well as the mean, concentration of NO 2 in school (median 21.1 μg/m3; mean 29.4 μg/m3) and office settings (median 22.7 μg/m3; mean 25.1 μg/m3) was well below the World Health Organization (WHO) guideline of 40 μg/m3 for the annual mean NO 2 concentration. However, a large range of average concentrations of NO 2 were reported, from 6.00 to 68.5 μg/m3 and from 3.40 to 56.5 μg/m3 for school and office environments, respectively, indicating situations where the WHO guidelines are exceeded. Outdoor levels of NO 2 are a reliable predictor of indoor NO 2 levels across seasons, with mean and median Indoor/Outdoor (I/O) ratios of 0.9 and 0.7 in school and 0.9 and 0.8 in office environments, respectively. The absence of major indoor NO 2 emission sources and NO 2 sinks, including chemical reactions and deposition, are the reasons for lower indoor NO 2 concentrations. During the winter, outdoor NO 2 concentrations are generally higher than during the summer. In addition, various building and indoor environment characteristics, such as type of ventilation, air exchange rates, airtightness of the envelope, furnishing and surface characteristics of the building, location of the building (urban versus suburban and proximity to traffic routes), as well as occupants' behavior (such as opening windows), have been statistically significantly associated with indoor NO 2 levels in school and office environments. Indoor exposure to NO 2 from the infiltration of ambient air can be significant in urban areas, and in the case of high traffic volume. Although reducing transportation emissions is challenging, there are several easier means to reduce indoor NO 2 concentrations, including a ventilation strategy with suitable filters; location planning of new schools, classrooms, and ventilating windows or intakes; traffic planning (location and density); and reducing the use of NO 2 -releasing indoor sources. • The level of NO 2 in ambient air is strongly related to the population and traffic density. • NO 2 is a health risk in outdoor and indoor air, and must be minimized. • The median indoor concentration of NO 2 was 26.1 μg/m3 and 22.7 μg/m3 in schools and offices, respectively. • The median Indoor/Outdoor (I/O) NO 2 ratio was 0.7 and 0.8 in schools and offices, respectively. • The mean NO 2 concentration in schools and offices is statistically significantly higher in Oceania and Asia than in Europe. [ABSTRACT FROM AUTHOR]

The emissions of volatile organic compounds (VOCs) from building materials may significantly contribute to indoor air pollution, and VOCs have been associated with odor annoyance and adverse health effects. Wood materials together with coatings are commonly used indoors for furniture and large surfaces such as walls, floors, and ceilings. This leads to high surface‐to‐volume ratios, and therefore, these materials may participate remarkably to the VOC levels of indoor environment. We studied emissions of VOCs and carbonyl compounds from pinewood (Pinus sylvestris) boards of 10% and 16% moisture contents (MC) with three paints using small‐scale test chambers (27 L). The emissions from uncoated pinewood and paints (on a glass substrate) were tested as references. The 28‐day experiment showed that the VOC emissions from uncoated pinewood were lower from sample with 16% MC. Painted pinewood samples showed lower emissions compared to paints on glass substrate. Additionally, paints on 16% MC pinewood exhibited lower emissions than on drier 10% MC wood. The emissions from painted pinewood samples were dominated by paint‐based compounds, but the share of wood‐based compounds increased over time. However, we noticed differences between the paints, and wood‐based emissions were clearly higher with the most permeable paint. [ABSTRACT FROM AUTHOR]

Degrading 2‐ethylhexyl‐containing PVC floorings (eg DEHP‐PVC floorings) and adhesives emit 2‐ethylhexanol (2‐EH) in the indoor air. The danger of flooring degradation comes from exposing occupants to harmful phthalates plasticisers (eg DEHP), but not from 2‐EH as such. Since the EU banned the use of phthalates in sensitive applications, the market is shifting to use DEHP‐free and alternative types of plasticisers in PVC products. However, data on emissions from DEHP‐free PVC floorings are scarce. This study aimed at assessing the surface and bulk emissions of two DEHP‐free PVC floorings over three years. The floorings were glued on the screed layer of concrete casts at 75%, 85%, and 95% RH. The volatile organic compounds (VOCs) were actively sampled using FLEC (surface emissions) and micro‐chamber/thermal extractor (µ‐CTE, bulk emissions) onto Tenax TA adsorbents and analyzed with TD‐GC‐MS. 2‐EH, C9‐alcohols, and total volatile organic compound (TVOC) emissions are reported. Emissions at 75% and 85% RH were similar. As expected, the highest emissions occurred at 95% RH. 2‐EH emissions originated from the adhesive. Because the two DEHP‐free floorings tested emitted C9‐alcohols at all tested RH, it makes the detection of flooring degradation harder, particularly if the adhesive used does not emit 2‐EH. [ABSTRACT FROM AUTHOR]

Bacillus anthracis infecting cattle is usually identified based on the typical symptom: sudden death. Bacillus anthracis causing atypical symptoms may remain undiagnosed and represent a potential occupational health hazard for, that is veterinarians and producers, butchers and tanners. In the year 2004, one case of sudden death in a dairy farm in southern Finland was diagnosed as bovine anthrax. Four years later 2008, an atypical case of anthrax was diagnosed in the same holding. The bull was taken to the Production Animal Hospital of the Faculty of Veterinary Medicine, University of Helsinki because of fever, loss of appetite and a symmetrically swollen scrotal sac. Penicillin treatment cured the fever but not the swollen scrotum. Before the intended therapeutic castration, a punctuate consisting of 10 ml fluid collected into a syringe from the scrotal sac was cultivated on blood agar at 37°C. After 24 hr, an almost pure culture of a completely non‐hemolytic Bacillus cereus‐like bacteria was obtained. The strain was identified as B. anthracis using Ba‐specific primers by the Finnish Food Safety Authority (RUOKAVIRASTO). After the diagnosis, the bull was euthanized and destroyed, the personnel were treated with prophylactic antibiotics and the clinic was disinfected. In this particular case, treatment with water, Virkon S and lime seemed to be effective to eliminate endospores and vegetative cells since no relapses of anthrax have occurred in 10 years. This case is the last reported anthrax case in Finland. [ABSTRACT FROM AUTHOR]

Moisture excess in buildings constitutes a complex problem affecting indoor air quality, energy consumption and the lifetime of the building envelope. We investigate the effect on moisture transfer in structures as a positive pressure is applied inside the enclosure. It is found that, contrary to established belief, the positive pressure does not induce any negative effects on the structures' moisture content in normally ventilated classrooms, even with high occupancy. Our case study consists of a school building in Finland, subject to temperature and relative humidity measurements after a small (5–7 Pa) positive pressure was realized through ventilation control. We first address analytically the moisture excess generated inside the classrooms for 14 days, using dynamical balance equations that account for both ventilation effects and occupants' moisture release in the environment. It is found that the average moisture excess is very small, largely below 1 g/m3, even for ventilation rates that are half the design value. We also examine the moisture performance of the envelope, by addressing the moisture migration at upper and lower joints of the external walls for both measured and design values of the indoor absolute humidity (AH). A coupled numerical model of diffusion and convection shows that moisture accumulation in the envelope and the according stresses are negligible for any realistic AH values. This result is in agreement with field measurements at the school. In conclusion, it seems that applying a small overpressure in a well-ventilated school building during a standard service period resulted in no accumulation inside the external walls, even at high occupancy and with low ventilation. Remarkably, it slightly dried out the moisture content in structures under actual occupancy conditions. The positive pressure has accordingly no negative effects on moisture performance, and is capable to guarantee a good indoor air quality as well. [ABSTRACT FROM AUTHOR]

The built environment is the global sector with the greatest energy use and greenhouse gas emissions. As a result, building energy savings can make a major contribution to tackling the current energy and climate change crises. Fluid dynamics models have long supported the understanding and optimization of building energy systems and have been responsible for many important technological breakthroughs. As Covid-19 is continuing to spread around the world, fluid dynamics models are proving to be more essential than ever for exploring airborne transmission of the coronavirus indoors in order to develop energy-efficient and healthy ventilation actions against Covid-19 risks. The purpose of this paper is to review the most important and influential fluid dynamics models that have contributed to improving building energy efficiency. A detailed, yet understandable description of each model's background, physical setup, and equations is provided. The main ingredients, theoretical interpretations, assumptions, application ranges, and robustness of the models are discussed. Models are reviewed with comprehensive, although not exhaustive, publications in the literature. The review concludes by outlining open questions and future perspectives of simulation models in building energy research. [ABSTRACT FROM AUTHOR]

• Indoor air quality (IAQ) of schools with/without reported IAQ complaints were studied. • Indoor climate questionnaires were used to verify the categorisation of schools. • More cultivable airborne microbes were found in schools with reported IAQ complaints. • Trichoderma was found only in the schools with reported IAQ complaints. • Other IAQ-related measurements were unable to uncover reasons for IAQ complaints. Reported indoor air quality (IAQ) complaints are common even in relatively new or renovated school buildings in Finland. However, detecting the causes for complaints with commonly used indoor air measurements is difficult. This study presents data on perceived and measured IAQ in six comprehensive school buildings in Finland. The aim of this study was to discover the possible differences of perceived and measured IAQ between schools with reported IAQ complaints and schools without reported IAQ complaints. The initial categorisation of schools with ('problematic schools') and without ('comparison schools') complaints was ensured via a validated indoor climate survey and a recently developed online questionnaire, which were completed by 186 teachers and 1268 students from the six schools. IAQ measurements of physical parameters, gaseous pollutants, particulate matter and bioaerosols were conducted in four problematic school buildings (26 classrooms) and two comparison school buildings (12 classrooms). Using air sampling as well as exhaust air filters and classroom settled dust to detect the presence of elevated concentrations of airborne cultivable microbes and pathogenic, toxigenic and mycoparasitic Trichoderma strains were the most indicative methods in distinguishing problematic schools from comparison schools. Other IAQ-related measurements did not detect clear differences between problematic and comparison schools, as the concentration levels were very low. The results indicate that the complaints reported by occupants could have been related to excess moisture or mould problems that had not been found or repaired. Ventilation pressure condition investigations and simultaneous exhaust and supply air filter dust culture should be addressed precisely in future studies. [ABSTRACT FROM AUTHOR]

The diversity of Chaetomium-like isolates in buildings in Finland is poorly documented. This paper describes a set of methods for rapid diversity tracking of 42 indoor Chaetomium-like isolates. These isolates were categorized based on their fluorescence emission, ascomatal hair morphology, responses in three bioassays and resistance/sensitivity to the wetting agent Genapol X-080. Thirty-nine toxigenic isolates were identified [Ch. globosum (n = 35), Ch. cochliodes (n = 2) and Ch. rectangulare (n = 2)]. These isolates were identified down to the species level by tef1α gene sequencing. The major toxic substances in the ethanol extracts of the Ch. globosum and Ch. cochliodes strains were chaetoglobosin, chaetoviridin A and C, chaetomugilin D and chaetomin, identified based on HPLC-UV and mass spectrometry data (MS and MS/MS). Ethanol extracts from pure Ch. globosum cultures exhibited a toxicological profile in the boar sperm motility inhibition assay (BSMI), sperm membrane integrity damage assay (SMID) and inhibition of cell proliferation (ICP) assay, similar to that exhibited by pure chaetoglobosin A. Overall, differences in fluorescence, morphology, toxicity profile, mycotoxin production and sensitivity to chemicals were consistent with those in tef1α sequencing results for species identification. The results indicate the presence of Ch. cochliodes and Ch. rectangulare in Finnish buildings, representing a new finding. [ABSTRACT FROM AUTHOR]

The occurrence and toxin production of the opportunistic pathogen Aspergillus calidoustus in Finnish buildings is not well documented in the literature. We tracked and identified four A. calidoustus colonies cultivated from indoor settled dusts and revealed the biological activities of crude biomass extracts. The toxic substances were identified as 6-epi-ophiobolin K, ophiobolin K, and ophiobolin G by high-performance liquid chromatography–mass spectrometry (HPLC-MS) based on chromatographic and mass spectrometry data (MS and MS/MS) on the crude extract of A. calidoustus strain MH34. A total of 29 fungal colonies collected from settled dust in an office room reported for indoor-air-related illnesses were screened for toxins that inhibited boar sperm motility in the BSMI (boar sperm motility inhibiting) assay and cell proliferation in the ICP (inhibition of cell proliferation) assays with PK-15 cells. Out of the 27 colonies tested as toxic, 12 colonies exhibiting conidiophores representative of the genera Chaetomium, Penicillium, and Paecilomyces were excluded from the study, while 13 colonies exhibited Aspergillus-like conidiophores. Biomass suspensions of these colonies were divided into two categories: Category 1 colonies (n = 4), toxic in the BSMI assay and the ICP assays, emitted blue fluorescence and grew at 37 °C; Category 2 colonies (n = 9), only toxic in the ICP assay, emitted orange fluorescence and exhibited limited or no growth at 37 °C. Colonies in Category 1 were pure-cultured, and the strains were named as MH4, MH21, MH34, MH36. Strain MH34 was identified as A. calidoustus by the internal transcribed spacer (ITS) sequences. Ethanol-soluble dry substances extracted from the biomass of the pure cultures exhibited a toxicological profile in the BSMI assay, SMID (sperm membrane integrity damage) assay, and ICP assay similar to that exhibited by pure ophiobolin A. Overall, the viable conidia of A. calidoustus in indoor settled dusts deserve attention when potentially hazardous mold species are monitored. [ABSTRACT FROM AUTHOR]

A novel, objective, and rapid computed motility inhibition (CMI) assay was developed to identify and assess sublethal injury in toxin-exposed boar spermatozoa and compared with a subjective visual motility inhibition (VMI) assay. The CMI values were calculated from digital micrographic videos using a custom MATLAB® script by contrasting the motility index values of each experiment with those of the background and control experiments. Following a comparison of the CMI and VMI assays results, it was determined that their agreement depended on the shape of the dose-response curve. Toxins that exhibited a steep slope were indicative of good agreement between the assays. Those depicted by a gentle decline in the slope of the dose-response curve, the CMI assay were shown to be two times more sensitive than the VMI assay. The CMI assay was highly sensitive to the inhibition of mitochondrial function and glucose transport activity by sublethal doses of toxins and to disruption of cellular cation homeostasis by carrier ionophoric toxins, when compared to the cytotoxicity and lethal toxicity assays (i.e., that evaluated the inhibition of cell proliferation in somatic cell lines (FL, PK-15, and MNA cells)) and disruption to spermatozoa membrane integrity. The CMI assay recognized subtle sublethal toxicity changes in metabolism, manifested as a decrease in boar spermatozoa motility. Thus, it was feasible to effectively compare the objectively-measured numerical values for motility inhibition using the CMI assay against those reflecting lethal damage in the spermatozoa cells and somatic cell lines using a cytotoxicity assay. [ABSTRACT FROM AUTHOR]

School environments are a complex entirety where various different exposure factors are related that contribute to the indoor air quality (IAQ) and may affect occupants’ health and well-being. Indoor air questionnaires are useful for collecting information about the occupants’ experiences and perceptions of the indoor air and for evaluating the results of the measures taken. A common way to implement health questionnaires is to ask the respondents to describe symptoms at certain time points, such as weeks or months. The aim of our study was to develop a short and easy online questionnaire to assess symptoms and perceived IAQ. We also aimed to test the usability of the questionnaire in school buildings and assess the differences between the online measurement data (CO2, T, and RH) and the IAQ complaints and symptoms reported by the pupils. A total of 105 teachers and 1268 pupils in 36 classrooms at six schools answered the questionnaires over a two-week period. The participants completed the questionnaire always after the lesson in the studied classroom. We received 719 answers from the teachers and 6322 answers from the pupils. The results demonstrated that the teachers reported more IAQ problems and symptoms than the pupils did. Differences between classrooms were observed in both the IAQ problem and reference schools. The most common significant differences (p-value > 0.05) between the classrooms were among humidity, too cold air, and stuffy air, and among symptoms, dry/sore throat, tiredness, headache, and skin symptoms. Maximum values of CO2 measurements and the highest prevalence of stuffy air were relatively consistent. The testing process demonstrated that such a questionnaire was suitable for adults and children aged at least 12 years. The results of our study suggest that a quick and easy online questionnaire that is completed within a short period may be useful for gathering valuable knowledge about perceived IAQ. It could be used in combination with other indoor environment investigations to produce detailed results and restorative measures. [ABSTRACT FROM AUTHOR]