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Copyright of Biomédica: Revista del Instituto Nacional de Salud is the property of Instituto Nacional de Salud of Colombia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the study was to compare the content of ergosterol in different microorganisms (bacteria, yeasts and moulds) isolated from the air as well as in six species of moulds in their different morphological forms-live mycelium, dead mycelium, and spores. Evaluation of the level of mould contamination of the air in various places using culture method and ergosterol determination was also performed. The analysis of ergosterol was carried out by gas chromatography equipped with flame ionisation detector. For evaluation of the results, analysis of variance and multiple comparison test were used. The quantity of ergosterol in the spores of various species of mould was in the range 1.9-9.4 pg/spore. The presence of yeasts and bacteria in the air does not significantly affect ergosterol concentration, in view of the low content of that sterol in their cells (max. 0.009 pg/cell for bacteria and 0.39 pg/cell for yeast). An ergosterol concentration above 1 ng per m can be considered an indicator of excessive mould contamination of indoor air. Based on determination of ergosterol in the air of mouldy rooms the result obtained may be compared with the culture method, due to the 1,000 times higher concentration of ergosterol in the mycelium compared with spores. However, in the analysis of outdoor air, in view of the presence of mould mainly in the form of spores and the degradation of ergosterol by UV radiation, analysis of that compound may indicate a lower level of contamination compared with the culture method. [ABSTRACT FROM AUTHOR]

Aiming to contribute with more data on the presence of SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) in outdoor environments, we performed air sampling in outdoor terraces from restaurants in three major cities of Portugal in April 2021, following the third wave lockdown release in the country. Air samples ( n =19) were collected in 19 restaurant terraces during lunch time. Each air sample was collected using a Coriolis Compact air sampler, followed by RNA extraction and real-time quantitative PCR for the detection of viral RNA. Viral viability was also assessed through RNAse pre-treatment of samples. Only one of the 19 air samples was positive for SARS-CoV-2 RNA, with 7337 gene copies m -3 for the genomic region N2, with no viable virus in this sample. The low number of positive samples found in this study is not surprising, as sampling took place in outdoor settings where air circulation is optimal, and aerosols are rapidly dispersed by the air currents. These results are consistent with previous reports stating that transmission of SARS-CoV-2 in outdoor spaces is low, although current evidence shows an association of exposures in settings where drinking and eating is possible on-site with an increased risk in acquiring SARS-CoV-2 infection. Moreover, the minimal infectious dose for SARS-CoV-2 still needs to be determined so that the real risk of infection in different environments can be accurately established.

Background concentrations of airborne fungi are indispensable criteria for an assessment of fungal concentrations indoors and in the ambient air. The goal of this study was to define the natural background values of culturable fungal spore concentrations as reference values for the assessment of moldy buildings. The concentrations of culturable fungi were determined outdoors as well as indoors in 185 dwellings without visible mold, obvious moisture problems or musty odor. Samples were collected using the MAS-100 ® microbiological air sampler. The study shows a characteristic seasonal influence on the background levels of Cladosporium , Penicillium and Aspergillus . Cladosporium sp. had a strong outdoor presence, whereas Aspergillus sp. and Penicillium sp. were typical indoor fungi. For the region of Styria, the median outdoor concentrations are between 100 and 940 cfu/m³ for culturable xerophilic fungi in the course of the year. Indoors, median background levels are between 180 and 420 cfu/m³ for xerophilic fungi. The I/O ratios of the airborne fungal spore concentrations were between 0.2 and 2.0. For the assessment of indoor and outdoor air samples the dominant genera Cladosporium , Penicillium and Aspergillus should receive special consideration. [ABSTRACT FROM AUTHOR]

This work investigated the impact of the HVAC filtration system and indoor particle sources on the relationship between indoor and outdoor airborne particle size and concentrations in an operating room. Filters with efficiency between 65% and 99.97% were used in the investigation and indoor and outdoor particle size and concentrations were measured. A balance mass model was used for the simulation of the impact of the surgical team, deposition rate, HVAC exhaust and air change rates on indoor particle concentration. The experimental results showed that high efficiency filters would not be expected to decrease the risk associated with indoor particles larger than approximately 1 µm in size because normal filters are relatively efficient for these large particles. A good fraction of outdoor particles were removed by deposition on the HVAC system surfaces and this deposition increased with particle size. For particles of 0.3–0.5 µm in diameter, particle reduction was about 23%, while for particles >10 µm the loss was about 78%. The modelling results showed that depending on the type of filter used, the surgical team generated between 93% and 99% of total particles, while the outdoor air contributed only 1–6%. [ABSTRACT FROM PUBLISHER]

Gas-flow ionization chambers for radioisotope (RI) monitoring systems at RI institutes throughout Japan are commonly used to measure RIs which leak from the RI institutes. Before the Japan's 2011 Tohoku earthquake [11 March 2011, moment magnitude ( M) 9.0], ionization current data measured with a gas-flow ionization chamber at the RI institute of Fukushima Medical University were found to change. The question we must raise is whether the variation ionization current can be considered to the variation of outdoor radon concentration. The conversion factors (from ionization current to radon concentration in air) of the gas-flow ionization chamber can be obtained by measuring four levels of radon concentration (outdoor air, indoor air, high level and radon-free gas) with an AlphaGUARD monitor and the chamber itself. The two gas-flow ionization chambers consist of the air intake and terminal exhaust duct of the RI institute. It was found that the radon concentration in the exhaust air was the same as that in the air intake. This study provided evidence that variations of outdoor radon concentration could be determined using gas-flow ionization chambers for RI monitoring systems. [ABSTRACT FROM AUTHOR]

Polybrominated diphenyl ethers (PBDEs) constitute an important group of brominated flame retardants that have been massively produced and extensively used in numerous everyday products, providing longer escape times in case of fire and thus saving lives, as well as reducing the damage of property. In recent years, PBDEs have been recognized as significant pollutants of the indoor environment. This article provides a synthesis and critical evaluation of the state of the knowledge about the occurrence of PBDEs in the indoor environment (air and dust in homes, workplaces and cars) in different countries in Europe, North America, Asia and Australia, as well as about the human exposure via indoor air inhalation and dust ingestion in comparison to outdoor air inhalation and dietary intake. [Copyright &y& Elsevier]

Background: Extreme temperatures have been associated with hospitalization and death among individuals with heart failure, but few studies have explored the underlying mechanisms. Objectives: We hypothesized that outdoor temperature in the Boston, Massachusetts, area (1- to 4-day moving averages) would be associated with higher levels of biomarkers of inflammation and myocyte injury in a repeated-measures study of individuals with stable heart failure. Methods: We analyzed data from a completed clinical trial that randomized 100 patients to 12 weeks of tai chi classes or to time-matched education control. B-type natriuretic peptide (BNP), C-reactive protein (CRP), and tumor necrosis factor (TNF) were measured at baseline, 6 weeks, and 12 weeks. Endothelin-1 was measured at baseline and 12 weeks. We used fixed effects models to evaluate associations with measures of temperature that were adjusted for time-varying covariates. Results: Higher apparent temperature was associated with higher levels of BNP beginning with 2-day moving averages and reached statistical significance for 3-and 4-day moving averages. CRP results followed a similar pattern but were delayed by 1 day. A 5°C change in 3-and 4-day moving averages of apparent temperature was associated with 11.3% [95% confidence interval (CI): 1.1, 22.5; p = 0.03) and 11.4% (95% CI: 1.2, 22.5; p = 0.03) higher BNP. A 5°C change in the 4-day moving average of apparent temperature was associated with 21.6% (95% CI: 2.5, 44.2; p = 0.03) higher CRP. No clear associations with TNF or endothelin-1 were observed. Conclusions: Among patients undergoing treatment for heart failure, we observed positive associations between temperature and both BNP and CRP-predictors of heart failure prognosis and severity. [ABSTRACT FROM AUTHOR]

Outdoor air pollution poses risks to human health in communities around the world, and research on populations who are most susceptible continues to reveal new insights. Human susceptibility to adverse health effects from exposure to air pollution can be related to underlying disease; demographic or anthropometric characteristics; genetic profile; race and ethnicity; lifestyle, behaviors, and socioeconomic position; and location of residence or daily activities. In health research, an individual or group may have an enhanced responsiveness to a given, identical level of pollution exposure compared to those who are less susceptible. Or, people in these different groups may experience varying levels of exposure (for example, a theoretically homogeneous population whose members differ only by proximity to a road). Often the information available for health research may relate to both exposure and enhanced response to a given dose of pollution. This paper discusses the general direction of research on susceptibility to air pollution, with a general though not an exclusive focus on particulate matter, with specific examples of research on susceptibility related to cardiovascular disease, diabetes, asthma, and genetic and epigenetic features. We conclude by commenting how emerging knowledge of susceptibility can inform policy for controlling pollution sources and exposures to yield maximal health benefit and discuss two areas of emerging interest: studying air pollution and its connection to perinatal health, as well as land use and urban infrastructure design. [ABSTRACT FROM AUTHOR]

Thailand border market is where the local Thais, Cambodians, Laotians, and Burmeses exchange their goods and culture at the border checkpoints. It is considered to be the source of aerial disease transmission especially for foreigners because it is always very crowded with people from all walks of life. Unhealthy air quality makes this area high risk of spread of airborne diseases. This study assessed airborne concentrations of bacteria and fungi in a border market to improve exposure estimates and develop efficient control strategies to reduce health risk. The density and distribution of airborne bacteria and fungi were investigated in the Chong Chom border market in Surin Province, Thailand. Eighteen air sampling sites were taken from outdoors and various work environments including indoor footpaths, wooden handicraft shops, electronic shops, the secondhand clothing shops, and fruit market areas. Exposed Petri plate method and liquid impinger sampler were used for sampling at the breathing zone, 1.5 m above the floor level, during weekend and holiday. Meteorological factors such as relative humidity, temperature, and light intensity were collected by portable data logger. The relative humidity was 67-73%, and temperature 29-33°C, and light varied between 18 and 270 Lux m. Gram-positive and Gram-negative bacteria were found at a mean value of 10 CFU m, and airborne fungi of 10 CFU m were recorded. The highest concentration of culturable airborne microorganisms was found along the indoor footpath (9.62 × 10 CFU m and 750.00 CFU/plate/h for impingement and sedimentation methods, respectively), the fruit market area (7.86 × 10 CFU m and 592.42 CFU/plate/h for impingement and sedimentation methods, respectively), and the secondhand clothing shop (4.59 × 10 CFU m and 335.42 CFU/plate/h for impingement and sedimentation methods, respectively) for Gram-positive bacteria, Gram-negative bacteria, and fungi, respectively. The lowest concentration of Gram-positive bacteria, Gram-negative bacteria, and fungi was found only at the outdoor area at 1.53 × 10 CFU m, 0.93 × 10 CFU m and 0.80 × 10 CFU m by means of impingement method and 136.67 CFU/plate/h, 69.25 CFU/plate/h, and 62.00 CFU/plate/h by means of sedimentation methods for Gram-positive bacteria, Gram-negative bacteria, and fungi, respectively. The most frequently present airborne bacteria were identified as Bacillus, Corynebacteria, Diplococcus, Micrococcus, Acinetobacter, Alcaligenes, Enterobacter, and spore former rods. Acremonium, Aspergillus, Cladosporium, Penicillium, and Sporotrichum were the most frequently found aerosol fungi genera. The distribution of airborne microorganisms correlated with relative humidity and light factors based on principal component analysis. In conclusion, the border market is a potential source of aerial disease transmission and a various hazards of bioaerosols for workers, consumers, sellers, and tourists. The bioaerosol concentration exceeded the standard of occupational exposure limit. Many major indicators of allergenic and toxigenic airborne bacteria and fungi, Acinetobacter, Enterobacter, Pseudomonas, Cladosporium, Alternaria, Aspergillus, and Penicillium, were found in the various market environments. [ABSTRACT FROM AUTHOR]

Background: Exposure to traffic-related air pollution is a risk factor for cardiovascular events, probably involving mechanisms of inflammation and coagulation. Little is known about effects of the short exposures encountered while participating in traffic. Objectives: The objective of the study was to examine effects of exposure of commuters to air pollution on cardiovascular biomarkers. Methods: Thirty-four healthy adult volunteers commuted for 2 hr by bus, car, or bicycle during the morning rush hour. During the commute, exposure to particle number, particulate matter (PM) ≤ 2.5 µm in aerodynamic diameter (PM2.5), PM ≤ 10 µm in diameter (PM10), and soot was measured. We estimated inhaled doses based on heart rate monitoring. Shortly before exposure and 6 hr after exposure, blood samples were taken and analyzed for CC16 (Clara cell protein 16), blood cell count, coagulation markers, and inflammation markers. Between June 2007 and June 2008, 352 pre- and postexposure blood samples were collected on 47 test days. We used mixed models to analyze the associations between exposure and changes in health parameters. Results: We observed no consistent associations between the air pollution exposures and doses and the various biomarkers that we investigated. Conclusions: Air pollution exposure during commuting was not consistently associated with acute changes in inflammation markers, blood cell counts, or blood coagulation markers. [ABSTRACT FROM AUTHOR]

Abstract: Aspergillus fumigatus is an opportunistic fungal pathogen that causes invasive aspergillosis, a usually fatal infection. The disease has risen in prominence in recent years due to the increasing numbers of severely immunocompromised patients becoming infected. The fungus is ubiquitous in the environment, producing large numbers of conidia that are dispersed in the air. Humans inhale numerous conidia everyday, but infections are not seen in healthy individuals. As inhalation of conidia is the main route of infection, considerable efforts are required to prevent infection in susceptible patients. This review summarises the current knowledge on airborne concentrations of A. fumigatus conidia, their background levels in outdoor air and seasonal distribution patterns. New and established methods of air sampling for airborne A. fumigatus conidia are discussed. Common environmental sources of the fungus are reviewed, including its presence in compost heaps. Finally, the lack of stringent guidelines on the monitoring and control of airborne A. fumigatus concentrations in hospitals is discussed. [Copyright &y& Elsevier]

BACKGROUND: Exposure to traffic-related air pollution (TRAP) contributes to increased cardio- vascular risk. Land-use regression models can improve exposure assessment for TRAP. OBJECTIVES: We examined the association between medium-term concentrations of black carbon (BC) estimated by land-use regression and levels of soluble intercellular adhesion molecule-1 (sICAM-1) and soluble vascular cell adhesion molecule-1 (sVCAM-1), both markers of inflammatory and endothelial response. METHODS: We studied 642 elderly men participating in the Veterans Administration (VA) Normative Aging Study with repeated measurements of sICAM-1 and sVCAM-1 during 1999-2008. Daily estimates of BC exposure at each geocoded participant address were derived using a validated spatiotemporal model and averaged to form 4-, 8-, and 12-week exposures. We used linear mixed models to estimate associations, controlling for confounders. We examined effect modification by statin use, obesity, and diabetes. RESULTS: We found statistically significant positive associations between BC and sICAM-1 for averages of 4, 8, and 12 weeks. An interquartile-range increase in 8-week BC exposure (0.30 μg/m3) was associated with a 1.58% increase in sICAM-1 (95% confidence interval, 0.18-3.00%). Overall associations between sVCAM-1 and BC exposures were suggestive but not statistically significant. We found a significant interaction with diabetes\where diabetics were more susceptible to the effect of BC\for both sICAM-1 and sVCAM-1. We also observed an interaction with statin use, which was statistically significant for sVCAM-1 and suggestive for sICAM-1. We found no evidence of an interaction with obesity. CONCLUSION: Our results suggest that medium-term exposure to TRAP may induce an increased inflammatory/endothelial response, especially among diabetics and those not using statins. [ABSTRACT FROM AUTHOR]

BACKGROUND: Epidemiological, controlled human exposure, and toxicological studies have demonstrated a variety of health effects in response to particulate matter (PM) exposure with some of these studies indicating that populations with certain characteristics may be disproportionately affected. OBJECTIVE: To identify populations potentially at greatest risk for PM-related health effects, we evaluated epidemiological studies that examined various characteristics that may influence susceptibility, while using results from controlled human exposure and toxicological studies as supporting evidence. Additionally, we formulated a definition of susceptibility, building from the varied and inconsistent definitions of susceptibility and vulnerability used throughout the literature. DATA SYNTHESIS: We evaluated recent epidemiological studies to identify characteristics of populations potentially susceptible to PM-related health effects. Additionally, we evaluated controlled human exposure and toxicological studies to provide supporting evidence. We conducted a comprehensive review of epidemiological studies that presented stratified results (e.g., < 65 vs. ≥ 65 years of age), controlled human exposure studies that examined individuals with underlying disease, and toxicological studies that used animal models of disease. We evaluated results for consistency across studies, coherence across disciplines, and biological plausibility to assess the potential for increased susceptibility to PM-related health effects in a specific population or life stage. CONCLUSIONS: We identified a diverse group of characteristics that can lead to increased risk of PM-related health effects, including life stage (i.e., children and older adults), preexisting cardiovascular or respiratory diseases, genetic polymorphisms, and low-socioeconomic status. In addition, we crafted a comprehensive definition of susceptibility that can be used to encompass all populations potentially at increased risk of adverse health effects as a consequence of exposure to an air pollutant. [ABSTRACT FROM AUTHOR]

Background: Exposure to airborne particulate matter (PM), a major component of air pollution, has been associated with increases in both exacerbations of and hospitalizations for asthma. We have previously shown that exposure to ambient PM collected in urban Baltimore (AUB) induces airway hyperresponsiveness (AHR), eosinophilic and neutrophilic inflammation, and the recruitment of T cells. However, the mechanism(s) by which it induces these features of asthma remains unknown. Objective: We investigated whether T lymphocytes play a role in AUB-induced AHR. Methods: We compared the effects of AUB exposure on the allergic phenotype in wild-type (WT) BALB/c mice and in mice deficient in recombinase-activating gene-1 (Rag1-/-) that lack mature lymphocytes. Results: We found that exposure of WT mice to AUB induced AHR concomitant with increases in the numbers of bronchoalveolar lavage (BAL) fluid lymphocytes, eosinophils, neutrophils, and mucus-containing cells in the lungs of WT mice. Interestingly, we show for the first time that these effects were associated with significant elevations in interleukin (IL)-17A, IL-17F, and T-helper 2 cell (TH2) (IL-13, IL-5) cytokine levels in lung cells, as well as reductions in the levels of the suppressive cytokine IL-10. Interestingly, Rag1-/- mice failed to develop AUB-induced AHR; however, AUB-induced BAL fluid cellularity, and mucus cell changes were only partially inhibited in Rag1-/- mice. Conclusions: Taken together, our results suggest that AUB exposure increases the pathophysiological features of asthma via activation of lymphocyte-dependent pathways. These results provide a plausible biological mechanism for the strong association between PM exposure and the increased severity of asthma. [ABSTRACT FROM AUTHOR]

The extensive flooding in the aftermath of Hurricanes Katrina and Rita created conditions ideal for indoor mold growth, raising concerns about the possible adverse health effects associated with indoor mold exposure. Studies evaluating the levels of indoor and outdoor molds in the months following the hurricanes found high levels of mold growth. Homes with greater flood damage, especially those with >3 feet of indoor flooding, demonstrated higher levels of mold growth compared with homes with little or no flooding. Water intrusion due to roof damage was also associated with mold growth. However, no increase in the occurrence of adverse health outcomes has been observed in published reports to date. This article considers reasons why studies of mold exposure after the hurricane do not show a greater health impact. [ABSTRACT FROM AUTHOR]

Most investigations into the correlation between exposure to fungi and detrimental health effects focus on the 2-4 most prevalent genera in ambient air, both outdoors and indoors. Yet over 80 genera of fungi have been shown to have allergenic potential. Also, there is no agreement about threshold values for exposure to fungi. One of the fungal genera expected to be less prevalent in ambient air and known to cause allergy is Botrytis. In this review, we investigate the airborne exposure level and health effect of Botrytis, both at general exposure and in occupational settings. The surveyed papers show that Botrytis is found globally with different spore seasons depending on the region investigated. The levels of Botrytis in the percentage of all fungi have a calculated median of around 1.1% in the different environments, confirming that it is among the less prevalent fungi. Furthermore, a substantial proportion of patients and workers are allergic to Botrytis cinerea, and when B. cinerea was included in extended test panels additional allergic patients were found. Thus, B. cinerea is as important as the more prevalent mould genera Cladosporiuni and Alternaria and we suggest that it should be included in standard allergic tests panels. [ABSTRACT FROM AUTHOR]

Abstract: A novel gas-phase cleanup method was developed for use with a thermal desorption method for analysis of trace semivolatile organic compounds (SOCs) in the atmosphere using diffusion denuder samplers to separate gas-phase from particle-associated fractions. The cleanup selectively removed hydrogen-bonding chemicals from samples, including much of the background matrix of oxidized organic compounds that is present in ambient air samples. Abraham solvation parameters were found to be useful predictors of recovery of compounds through the cleanup method; most compounds with A + B <0.3 and L ≤12.3 were fully recovered through the cleanup method. Addition of the cleanup method successfully produced baseline resolution in air samples and improved method precision. The utility of the method was demonstrated in an investigation of the built environment as a continuing source of semivolatile persistent, bioaccumulative, and toxic chemicals (PBTs) to the atmosphere. [Copyright &y& Elsevier]

This study was investigated the density and monthly distribution of indoor and outdoor microfungi in six different residential houses in Tekirdag City through the exposure of Petri dishes containing Rose-Bengal Streptomycin Agar media. Samples were collected in 1-month intervals over a period of 12 months between March, 2001, and February, 2002. We used 432 Petri dishes and counted a total of 4,205 microfungi colonies, 1,790 from indoor air and 2,415 from outdoor air. As a result, 42 species belonging to 12 genera were identified. The most frequent fungal genera were Penicillium (28.61%), Cladosporium (16.08%) and Alternaria (15.98%). While Penicillium (40.61%) and Cladosporium (15.92%) were the dominant genera of indoor air, Alternaria (20.62%) and Penicillium (19.71%) were isolated most frequently from outdoor air (Table 3). Alternaria citri (10.15%) and Penicillium brevicompactum (10.15%) were found to be the most frequent among the 42 identified species. While P. brevicompactum (19.55%) and Aspergillus niger (6.37%) were the most frequent indoor species, A. citri (13.37%) and Cladosporium cladosporioides (8.20%) were the most frequent outdoor species. Linear Regression Analysis was applied to determine whether or not there was a relationship between the number of colonies of isolated fungal genera and meteorological factors during the research period. Correlations between the presence of Aspergillus and temperature, relative humidity, duration of sunny periods and agents of air pollution such as SO2 and PM were statistically significant. No significant correlations, however, were found between other fungal genera and environmental variables. [ABSTRACT FROM AUTHOR]

A personal cyclone sampler (cyclone) was operated continuously alongside a 25-mm filter sampler (filter), a slit impactor (Burkard slide), and a high-volume cyclone sampler (Burkard cyclone) at an outdoor location with abundant naturally occurring fungi (N = 30; sampling time: 12.5 ± 2.3 hr). Air concentrations (spore m-3) of 28 fungal groups were determined for all samplers by microscopy. Cyclone performance was judged using various indices to determine if it agreed with the other samplers in determination of the frequencies with which the fungal groups were observed, as well as their proportions of the total air concentration. Fungal diversity estimates were similar for all samplers and in the range of what has been reported nationally, i.e., observation of 9-11 equal groups per sample, but spore concentration dominated by 2-3 groups. Plots of paired cyclone:comparison sampler ratios against average concentrations identified biases. For example, ratios were correlated with concentration and there was greater uncertainty at lower concentrations. Mean ratios for cyclone:filter comparisons were not significantly different from one for ascospores, Aspergillus-Penicillium spp., basidiospores, Cladosporium spp., or total spore m-3. However, agreement was less consistent with the Burkard slide (0.74, 1.12, 0.91, 1.09, and 0.92, respectively) and the Burkard cyclone (2.31, 1.62, 1.43, 1.91, and 1.33, respectively). Concentrations of cell equivalent m-3 also were determined for the filter and two cyclone samples by polymerase chain reaction. Cell equivalents for Aspergillus fumigatus and Penicillium brevicompactum were compared with Aspergillus-Penicillium spp. spores, and Cladosporium cladosporioides and Cladosporium herbarum cell equivalents were compared with Cladosporium spp. spores. Cell equivalent:spore ratios below one for A. fumigatus and P. brevicompactum indicated that these species comprised smaller factions of total spores or were collected less efficiently than the larger C. cladosporioides and C. herbarum spores. The personal cyclone was shown to be suitable for collection of ambient airborne fungal spores and for analysis by microscopy and polymerase chain reaction. [ABSTRACT FROM AUTHOR]

The article presents a study on the seasonal variation in outdoor air microbial concentrations and differences between the landfill, urban, and rural environments. It examines the filter samples for ergosterol and examines 14 species of fungi and bacterial genus by using quantitative PCR. The study provides baseline information concentrating the composition of outdoor air bioaerosols in different seasons and environments in the subarctic climate for subsequent risk assessment. It concludes that both season and environment are determinants of the microbial communities and outdoor air.

Regulatory action levels for benzene in indoor air are typically unrealistic because they are commonly less than ambient outdoor concentrations. To trace potential benzene contributions to indoor air from outdoor sources, we evaluated data from 66 air samples collected at three sites with known subsurface impacts. Comparison of benzene:tracer ratios from indoor air, outdoor air, and soil gas samples demonstrated that indoor air benzene was primarily contributed by outdoor air and not by soil-vapor intrusion. Principal components analysis also demonstrated that soil gas had a distinctly different volatiles signature than both indoor and outdoor air. Ignoring ambient outdoor benzene contributions may lead to the erroneous conclusion that soil gas is the source of indoor air benzene. [ABSTRACT FROM AUTHOR]

Abstract: In this article, a new design for reversible air–air heat pumps is proposed. This design is not based on the refrigerant changeover, as is proposed by ASHRAE, but rather is based on the inversion of the air flow on the ducts. Thanks to this modification it is possible to use any air–air refrigeration machine for air conditioning as a reversible heat pump. The new design is more efficient, especially when the building requires greater air quality and therefore a larger amount of outdoor air. It also increases its efficiency as the outdoor temperatures become more extreme. This improvement will make it possible to use heat pumps, with acceptable performances, in more rigorous climates than those in which they are used today. [Copyright &y& Elsevier]

Mold specific quantitative PCR (MSQPCR) was used to measure the concentrations of the 36 mold species in indoor and outdoor air samples that were taken simultaneously for 48 h in and around 17 homes in Cincinnati, Ohio. The total spore concentrations of 353 per m3 of indoor air and 827 per m3 of outdoor air samples were significantly different (p ≤0.05). However, only the concentrations of Aspergillus penicillioides, Cladosporium cladosporioides types 1 and 2 and Cladosporium herbarum were correlated in indoor and outdoor air samples (p-value≤0.05 and sufficient data for estimate and absolute value rho estimate ≥0.5). These results suggest that interpretation of the meaning of short-term (<48 h) mold measurements in indoor and outdoor air samples must be made with caution. [Copyright &y& Elsevier]

Fungal spores are transported across great distances in the outdoor air and are also regularly found indoors. Building conditions and behavior-related problems in apartments may lead to massive growth of mold within a very short period of time. The aim of this study was to evaluate whether the visible growth of mold indoors influences the concentration of fungal spores in the air as well as the variety of their species. Samples were collected from 66 households in Austria. For each sampling, the corresponding outdoor air was measured as reference value. The size of the visible mold growth was categorized in order to correlate the extent of mold growth with the concentration of airborne spores as well as the fungal genera. In order to determine fungal spore concentrations in the air, the one-stage MAS-100® air sampler was used. Malt extract agar (MEA) and dichloran glycerol agar (DG18) plates were used as culture media. The total colony forming units (CFU) per m3 were determined. The fungi were identified from the isolated colonies. The results show that in apartments visibly affected by mold, the median values were significantly higher than those of apartments without visible mold growth. The extent of visible mold growth is significantly correlated with both concentration of fungal spores (p<0.001) as well as the predominance of Penicillium sp. and Aspergillus sp. (p<0.001) in indoor air. The total fungal concentration of Penicillium and Aspergillus in the air of apartments is recommended for assessing fungal exposure. [Copyright &y& Elsevier]

There are limited data on exposures to ambient air toxics experienced by inhabitants of urban areas in developing countries that have high levels of outdoor air pollution. In particular, little is known about exposures experienced by individuals working outdoors – typically as part of the informal sector of the economy – as compared to workers in office-type environments that approach the indoor air quality conditions of the more developed countries. The objective of this study is to explore these differences in personal exposures using a convenience sample of 68 outdoor and indoor workers living in Mexico City (higher outdoor air pollution) and Puebla (lower outdoor air pollution), Mexico. Occupational and non-occupational exposures to airborne volatile organic compounds (VOCs) were monitored during a 2 day period, monitoring 2 consecutives occupational and non-occupational periods, using organic vapor monitors (OVMs). Socio-demographic and personal time–location–activity information were collected by means of questionnaires and activity logs. Outdoor workers experienced significantly higher exposures to most VOCs compared to indoor workers in each of these cities. The outdoor workers in Mexico City had the highest exposures both during-and off-work, with maximum occupational exposures for toluene, MTBE, n-pentane, and d-limonene exceeding 1 mg/m3. The inter-city pattern of exposures between the outdoor workers is consistent with the higher outdoor air pollution levels in Mexico City, and is above exposures reported for urban areas of the more developed countries. Results from this study suggest that elevated outdoor air pollution concentrations have a larger impact on outdoor workers'' personal exposures compared to the contribution from indoor pollution sources. This contrasts with the more dominant role of indoor air VOC contributions to personal exposures typically reported for urban populations of the more developed countries. [Copyright &y& Elsevier]

Abstract: Concentrations of 38 organic air pollutants including aromatic hydrocarbons (AHCs), carbonyl compounds (CCs), volatile organic halogenated compounds (VOHCs), and organophosphorus compounds (OPCs) were measured in indoor and outdoor air in an industrial city, Shimizu, Shizuoka Prefecture, Japan. Levels of pollutants tended to be higher indoors than outdoors in both summer and winter except for benzene, carbon tetrachloride, trichloroethylene, tetrachloroethylene, and dichlorvos (DDVP). This trend was especially pronounced for CCs such as formaldehyde and acetaldehyde. For the organic air pollutants, the concentrations of AHCs and VOHCs substantially increased in winter, but not those of CCs and OPCs; the trends were similar for both indoors and outdoors. We investigated possible indoor sources of pollutants statistically. Multiple regression analysis of corresponding indoor and outdoor concentrations and the responses to our questionnaire showed that indoor concentrations of certain AHCs were significantly affected by their outdoor concentrations and cigarette smoking. For formaldehyde, indoor concentrations were significantly affected by house age and the presence of carpet or pets. For p-dichlorobenzene (pDCB), the concentrations in bedroom trended to be higher than those in other indoors and outdoors, suggested that mothballs for clothes present in bedrooms are the principal indoor source of pDCB. We compared indoor and outdoor pollutant concentrations to acceptable risk limits for 11 organic air pollutants. In indoors without smoking samples, the geometric mean concentrations of benzene, formaldehyde, acetaldehyde, carbon tetrachloride, pDCB, and DDVP exceeded the equivalent concentration representing the upper bound of one-in-one-hundred-thousand (1×10−5) excess risk over a lifetime of exposure. [Copyright &y& Elsevier]

Abstract: In this study, the culturability of indoor and outdoor airborne fungi was determined through long-term sampling (24-h) using a Button Personal Inhalable Aerosol Sampler. The air samples were collected during three seasons in six Cincinnati area homes that were free from moisture damage or visible mold. Cultivation and total microscopic enumeration methods were employed for the sample analysis. The geometric means of indoor and outdoor culturable fungal concentrations were 88 and 102colony-forming units (CFU) m−3, respectively, with a geometric mean of the I/O ratio equal to 0.66. Overall, 26 genera of culturable fungi were recovered from the indoor and outdoor samples. For total fungal spores, the indoor and outdoor geometric means were 211 and 605sporesm−3, respectively, with a geometric mean of I/O ratio equal to 0.32. The identification revealed 37 fungal genera from indoor and outdoor samples based on the total spore analysis. Indoor and outdoor concentrations of culturable and total fungal spores showed significant correlations (, p<0.0001 and , p<0.0001, respectively). The indoor and outdoor median viabilities of fungi were 55% and 25%, respectively, which indicates that indoor environment provides more favorable survival conditions for the aerosolized fungi. Among the seasons, the highest indoor and outdoor culturability of fungi was observed in the fall. Cladosporium had a highest median value of culturability (38% and 33% for indoor and outdoor, respectively) followed by Aspergillus/Penicillium (9% and 2%) among predominant genera of fungi. Increased culturability of fungi inside the homes may have important implications because of the potential increase in the release of allergens from viable spores and pathogenicity of viable fungi on immunocompromised individuals. [Copyright &y& Elsevier]

Caring for indoor air quality (IAQ) in so-called non-industrial areas has become increasingly common. Because of people's awareness of hazards related to the presence of different substances in indoor air. A review with 103 references concerning the presence of organic compounds in non-industrial indoor environments is discussed. The main sources of indoor air pollutants are presented. Topics discussed also include: total volatile organic compounds (TVOC) concepts in IAQ evaluation, concentrations of organic compounds in indoor and outdoor air, and the influence of outdoor air on indoor air quality expressed as ratios of indoor (I) to outdoor (O) concentrations (I/O). [ABSTRACT FROM AUTHOR]

Abstract: The regional distributions of, and inhalation cancer risks for, a group of volatile organic hydrocarbons (VOCs) consisting of aromatic hydrocarbons (AHCs), volatile organic halogenated compounds (VOHCs), and carbonyl compounds (CCs) were determined in an industrial harbor city (Shimizu, Japan) in the summer and winter of 2000. The concentrations of most of these VOCs tended to be higher in winter than in summer, but this trend was not observed for CCs. Significant correlations () were observed between the concentrations of most of the AHCs in both summer and winter, and between the concentrations of certain AHCs and CCs in summer, which suggests common emission sources and similar atmospheric behavior for these compounds. The results of principal-component analysis indicated that vehicle exhaust and industrial activity were the predominant emission sources of the VOCs. To determine the local spatial distributions and emission sources for the VOCs, we created contour maps for the monitored VOCs. These maps indicated that the local distributions varied dramatically depending on the characteristics of the VOCs, such as their emission sources and fates. The lifetime cancer risks (LCRs) calculated from the corresponding VOC concentrations were significantly higher () in winter than in summer. Risk was derived mainly from benzene, carbon tetrachloride, formaldehyde, and acetaldehyde in both summer and winter; the spatial distribution of high LCR levels was similar to the distribution of high benzene, formaldehyde, and acetaldehyde concentrations. [Copyright &y& Elsevier]

Culturable airborne fungal spore sampling at five building sites during 2002–2003 provided a bank of outdoor data (102 samples total) to evaluate differences in levels of individual species of airborne fungi during the morning and afternoon hours. A minimum of 15 (outdoor) airsamples was collected at each site, and data were segregated into morning (beforenoon) and afternoon subsets. Significant differences in airborne levels for all detected fungal types between the morning and afternoon subsets were determined for each site, using a direct calculation of probability. Significance was defined by differences in frequency of detection above the combined median (p = 0.90 or greater) for the respective fungal type. The levels of various species of fungi in the outdoor air varied significantly between morning and afternoon data sets at all five sites, with no pattern by species, time of day, or location. Levels of Penicillium, Aspergillus, or other fungal species associated with problematic buildings if detected outdoors, can be significantly greater in the morning or afternoon (or exhibit no significant difference) on any given day. The data does not indicate laboratory analysis as a major contributor to the variability exhibited in bioaerosols, and underscores the necessity of collecting sufficient number of samples in the outdoor air in both the morning and afternoon to prevent bias when comparing a suspect indoor environment to outdoor conditions. [ABSTRACT FROM AUTHOR]

The microbial quality of the outdoor air in Poznań (Poland) was estimated by sedimentation method in the years 2002 and 2003. Microorganism concentration was high, the average monthly number of bacteria in 2002 often exceeded 3,000 cfu/m³ and reached in the summer 13,000 cfu/m³. At least 50% of airborne microorganisms were filamentous fungi. The concentration of two allergenic fungus genera Cladosporium and Alternaria estimated by Burkard trap reached in summer months 11,000 spores/m³ in 2002 and 16,000 spores/m³ in 2003. Airborne microorganism concentrations varied and changed with seasons and years, depending on sampling site and method of determination. [ABSTRACT FROM AUTHOR]

Abstract: A sensitive grab sampling technique was used to measure the equilibrium equivalent concentration of radon (Rn) progeny, EEC, outdoors at Bathinda, Punjab (India), over a period of 6 months. The method was based on the beta counting of aerosol samples collected on glass micro-fiber filters by drawing the air through the filters. Measurements, covering two of the three sessions of the day (morning, afternoon, evening), were performed two times per day at a fixed place at a height of 1.8m above the ground surface. The total average value of EEC was 5.62Bqm, while the morning, afternoon and evening averages were 9.15, 2.85 and 5.33Bqm, respectively. Negative correlation was observed for air temperature and EEC, while positive correlation was found for relative humidity and EEC, EEC was higher in winter than in summer. [Copyright &y& Elsevier]

Indoor and outdoor concentrations of particle matter (PM) and associated polycyclic aromatic hydrocarbons (PAHs) in summer and winter in two industrial cities in Shizuoka, Japan, were determined. Fine particles (PM2.5) accounted for 44–56% of the total suspended PM. Most (>80%) of the PAHs associated with the particles were in the PM2.5 fraction. The concentration of PAHs, but not particles, was elevated in winter. A strong correlation (p < 0.01) between indoor and outdoor air was found for almost PAHs measured, but not for particles. Ratios of indoor to outdoor PAH concentrations showed that the indoor PAHs were mostly from outdoor sources, and the trends were especially noticeable in winter. In spite of the high contribution of PAHs to PM2.5, no significant correlation was found between the concentration of PM2.5 and the associated PAH concentration either indoors or outdoors. Outdoors, individual relative PAH concentrations (normalized to benzo[e]pyrene concentration) were greater in winter than in summer for light molecular PAHs (∼4 rings), as well as for benzo[a]pyrene (BaP), whereas the seasonal differences for other heavy molecular PAHs (except BaP) were negligible. This suggested that the contributions of decay reactions such as photodegradation were relatively small for the heavy molecular PAHs. Carcinogenic risks associated with the inhalation of indoor PAHs were assessed, and BaP showed the greatest contribution (51–64%) to the total carcinogenic risk. [Copyright &y& Elsevier]

Fungal airborne spores were studied from September 1996throughout August 1997 in Santiago, Chile. Total concentrationsfluctuated between 308 and 10,334 spores/m3/day withan annual mean of 2,154 per m3, the highest dispersion beingduring April and May. Forty-five percent of total fungal content wasfound in autumn. Thirteen genera and 3 other spore types wereidentified. Cladosporium, the most abundant genera in ouratmosphere, contributed with 70.9% of the total fungi counts andreached an annual mean of 1,527 spores/m3/day, itshighest frequency being in autumn. Alternaria appeared as thesecond most frequent genera, with an annual mean of 40spores/m3/day, representing a 1.9% of theannual fungal catch. Altogether, Stemphylium, Torula, Epicoccum,Ganoderma, Helminthosporium, Chaetomiun, Pleospora and othersreached relative frequencies of 0.5% or less. It is concludedthat fungi are present in Santiago's atmosphere all year round, some ofthem with a clear seasonality. [ABSTRACT FROM AUTHOR]

One of the greatest environmental health problems to arise in recent years is air pollution. Inorganic and organic particles are important components of air aerosol. The potential of air microbiota as an indicator of air quality is gaining increasing research interest. The aim of the present study was to determine the relationship between the level of fungal contamination and the levels of bacteria and smog particles in outdoor air in recreational areas during the heating season. A quantitative and qualitative mycological evaluation and quantitative bacteriological evaluation of air quality in 10 selected parks were performed. The numbers of microorganisms in the air were correlated with smog levels. The mean prevalence of fungi was 18.96 ± 15.43–23.30 ± 26.70 CFU/m3 of air and the mean bacterial count was 74.06 ± 130.89–268.04 ± 126.10 CFU/m3. Among the isolated fungi, clinically significant species were identified: four species belonged to Risk Group 2, and 17 to Risk Group 1. The predominant genera were Aspergillus, Penicillium and Alternaria. The total number of bacteria demonstrated a positive correlation with the size of the park, air temperature and ozone level during sampling, and a negative correlation with humidity, pressure and smog parameters (CO, NO, NO2 and NOx). The qualitative and quantitative composition of bioaerosols can be used as a bioindicator for environmental monitoring. There is a need for more efficient monitoring of airborne pollutants and microorganisms to learn about the structure of the air biota, the mechanisms regulating their occurrence, and to identify potential threats to human health. [ABSTRACT FROM AUTHOR]

The concentrations of radon, thoron and terrestrial gamma radiation were measured to evaluate the outdoor effective dose. The outdoor radon activity concentration ranged from 5.79 to 5110 ± 46.36 Bq m−3, with a mean of 320.03 Bq m−3 which is higher than the EPA level of 14.8 Bq m−3. The range of the thoron activity concentration outdoor was from 0.00 to 4226.7 ± 58.5 Bq m−3, with a mean of 226.1 Bq m−3 which was above the UNSCEAR recommended level of 10 Bq m−3. The terrestrial gamma radiation dose rates range was from 98.31 to 3769.71 nGy h−1 with a mean of 446.27 nGy h−1. The effective dose contribution from radon exposures in the study was estimated to be 3.2 ± 0.5 mSv y−1 is about 84% total annual effective dose received by the population in those areas. The estimated thoron and gamma dose contributions (15%, and 1% respectively) were not significant. The outdoor doses for thoron and gamma were lower than the ICRP (2007) value of 1 mSv. The total annual outdoor effective dose with an occupancy factor of 1825 h (5 h day−1) was estimated to be within the range of 0.30–551.41 ± 0.65 mSv, with a mean of 3.75 mSv which is a little higher than the world average of 2.4 mSv. • Radon (222Rn) and Thoron (220Rn) concentration measurements were carried out in outdoor air. • The mean 222Rn activity concentration in outdoor air was higher than the EPA level. • The mean 220Rn activity concentration in outdoor air was higher than the UNSCEAR level. • The total mean annual outdoor effective dose was higher than the world average of 2.4 mSv • The 222Rn dose of the study location contributed most (84%) of the total effective dose outdoor. [ABSTRACT FROM AUTHOR]

The manuscript reports findings from a screening-level assessment of cancer risk from outdoor air in Aamjiwnaang First Nation. Ambient air pollution can contribute to cardiovascular/respiratory diseases, and certain types of cancer. Certain communities may be at higher risk to the negative health impacts due to their geographical proximity to pollution sources. Outdoor air concentrations were mapped and the Lifetime Excess Cancer Risks (LECR) associated with long-term exposure to known carcinogens were estimated. LECR results for both benzene and 1,3-butadiene were above one per million. The LECR for benzene was 6.4 per million when the Health Canada slope factor was applied and 12.0 when using the US EPA. For 1,3-butadiene the LECR estimate was 8.8 per million. This work provides a better understanding of environmental exposures and potential associated cancer risks for residents in the Aamjiwnaang community and highlights the need for further air monitoring and a more detailed risk assessment.