Air Samples Research Articles

Impact of air quality on the health of present-day workers in an Asbestos roof manufacturing industry, Sri Lanka.

The study's objective was to determine the air quality in an asbestos-related industry and its impact on current workers' respiratory health. Seventy-seven air and 65 dust samples were collected at 5-day intervals in an asbestos roofing sheets production factory in Sri Lanka having two production facilities. Sampling was performed in ten sites: Defective sheets-storage, Production-plant, Pulverizer, Cement-silo, and Loading-area. A detailed questionnaire and medical screening were conducted on 264 workers, including Lung Function Tests (LFT) and chest X-rays. Asbestos fibres were observed in deposited dust samples collected from seven sites. Free chrysotile fibres were absent in the breathing air samples. Scanning Electron Microscopy confirmed the presence of asbestos fibres, and the Energy Dispersive X-ray analysis revealed Mg, O, and Si in depositions. The average concentrations of trace metals were Cd-2.74, Pb-17.18, Ni-46.68, Cr-81.01, As-7.12, Co-6.77, and Cu-43.04mg/kg. The average Zn, Al, Mg, and Fe concentrations were within 0.2-163g/kg. The highest concentrations of PM2.52.5 and PM1010, 258 and 387µg/m3, respectively, were observed in the Pulverizer site. Forty-four workers had respiratory symptoms, 64 presented LFT abnormalities, 5 indicated chest irregularities, 35.98% were smokers, and 37.5% of workers with abnormal LFT results were smokers. The correlation coefficients between LFT results and work duration with respiratory symptoms and work duration and chest X-ray results were 0.022 and 0.011, respectively. In conclusion, most pulmonary disorders observed cannot directly correlate to Asbestos exposure due to negligible fibres in breathing air, but fibres in the depositions and dust can influence the pulmonary health of the employees.

Monitoring of enteropathogenic Gram-negative bacteria in wastewater treatment plants: a multimethod approach

The wastewater treatment processes are associated with the emission of microbial aerosols, including enteropathogenic bacteria. Their presence in this work environment poses a real threat to the health of employees, both through the possibility of direct inhalation of the contaminated air and indirectly through the pollution of all types of surfaces with such bioaerosol particles. This study aimed to investigate the prevalence of enteropathogenic bacteria in the air, on surfaces, and in wastewater samples collected in four wastewater treatment plants (WWTPs). The effectiveness of conventional culture-biochemical, as well as spectrometric and molecular methods for the rapid detection of enteropathogenic bacteria at workstations related to particular stages of wastewater processing, was also evaluated. Bioaerosol, surface swab, and influent and effluent samples were collected from wastewater plants employing mechanical–biological treatment technologies. The air samples were collected using MAS-100 NT impactor placed at a height of 1.5 m above the floor or ground, simulating aspiration from the human breathing zone. Surface samples were collected with sterile swabs from different surfaces (valves, handles, handrails, and coveyor belts) at workplaces. The raw influent and treated effluent wastewater samples were aseptically collected using sterile bottles. The identification of bacterial entheropathogens was simultaneously conducted using a culture-based method supplemented with biochemical (API) tests, mass-spectrometry (MALDI TOF MS), and molecular (multiplex real-time PCR) methods. This study confirmed the common presence of bacterial pathogens (including enteropathogenic and enterotoxigenic Escherichia coli, Salmonella spp., Campylobacter spp., and Yersinia enterocolitica) in all air, surface, and wastewater samples at studied workplaces. Higher concentrations of enteropathogenic bacteria were observed in the air and on surfaces at workplaces where treatment processes were not hermetized. The results of this study underline that identification of enteropathogenic bacteria in WWTPs is of great importance for the correct risk assessment at workplaces. From the analytical point of view, the control of enteropathogenic bacterial air and surface pollution using rapid multiplex-PCR method should be routinely performed as a part of hygienic quality assessment in WWTPs.

Evaluation of germicidal ultraviolet-C disinfection in a real-world outpatient health care environment

The coronavirus disease 2019 pandemic has highlighted the need for effective infection control in outpatient healthcare settings. Germicidal ultraviolet-C (GUV) light, known for inactivating microorganisms by damaging their deoxyribonucleic acid or ribonucleic acid, offers a potential solution. This study examines the efficacy of GUV air disinfection systems in real-world outpatient environments. We deployed upper-room and far-UV GUV fixtures in 3 outpatient facilities, assessing their impact on bacterial loads through air and surface sampling and bioindicator tests. Occupancy was also monitored. While manual air and surface sampling did not show a significant difference in bacterial loads between control and Ultraviolet C-treated groups, bioindicator tests demonstrated a high level of spore inactivation (up to 99.7% for upper-room GUV and 96.26% for far-UV). Occupancy levels did not significantly influence these outcomes. The discrepancy between bioindicator efficacy and environmental sampling results suggests limitations in the latter's ability to accurately capture environmental bioburden. Bioindicators proved to be reliable for in-situ validation of Ultraviolet C surface disinfection. Bioindicators are effective for validating GUV surface disinfection efficacy in healthcare settings, though further research is needed to optimize environmental sampling methods for assessing GUV's impact on real-world bacterial loads.

First detection of triazole-resistant aspergillus fumigatus harbouring the TR34/L98H Cyp51A mutation in Burkina Faso.

Triazole-resistant Aspergillus fumigatus (TRAF) isolates are a growing public health problem with worldwide distribution. Epidemiological data on TRAF is limited in Africa, particularly in West Africa. This study aimed to screen for the environmental presence of TRAF isolates in the indoor air of two hospitals in Burkina Faso. Air samples were collected in wards housing patients at risk for invasive aspergillosis, namely infectious diseases ward, internal medicine ward, nephrology ward, pulmonology ward, medical emergency ward and paediatric ward. Sabouraud Dextrose Agar supplemented with triazoles was used to screen the suspected TRAF isolates and EUCAST method to confirm the resistance of suspected isolates. Sequencing of cyp51A gene was used to identify the resistance mechanism of confirmed TRAF isolates. Of the 198 samples collected and analysed, 67 showed growth of A. fumigatus isolates. The prevalence of TRAF isolates was 3.23% (4/124). One TRAF isolate exhibited a pan-triazole resistance. Sequencing of cyp51A gene identified the TR34/L98H mutation for this pan-triazole resistant isolate. This study showed for the first time the circulation of the pan-azole resistant isolate harbouring the TR34/L98H mutation in Burkina Faso. These findings emphasise the need to map these TRAF isolates in all parts of Burkina Faso and to establish local and national continuous surveillance of environmental and clinical TRAF isolates in this country.

Comparison of active measurements, lichen biomonitoring, and passive sampling for atmospheric mercury monitoring

The number of atmospheric mercury (Hg) monitoring stations is growing globally. However, there are still many regions and locations where Hg monitoring is limited or non-existent. Expansion of the atmospheric Hg monitoring network could be facilitated by the use of cost-effective monitoring methods. As such, biomonitoring and passive monitoring offer a unique alternative to well-established monitoring by active measurements, since they do not require a power supply and require minimal workload to operate. The use of biomonitoring (lichens and mosses) and passive air samplers (PASs) (various designs with synthetic materials) has been reported in the literature, and comparisons with active measurement methods have also been made. However, these studies compared either biomonitoring or PASs (not both) to only one type of active measurement. In our work, we used transplanted (7 sampling sites) and in situ lichens (8 sampling sites) for biomonitoring, two PASs from different producers (3 sampling sites), and two different active measurement types (continuous and discontinuous active measurements, 1 and 8 sampling sites, respectively) to evaluate their effectiveness as monitoring methods. In the 9-month sampling campaign, 3 sampling locations with different characteristics (unpolluted, vicinity of a cement plant, and vicinity of a former Hg mine) were used. The results obtained with lichens and PASs clearly distinguished between sampling locations with different Hg concentrations; using both PASs and lichens together increased the confidence of our observations. The present work shows that biomonitoring and passive sampling can be effectively used to identify areas with elevated atmospheric Hg concentrations. The same can be said for discontinuous active measurements; however, the discrepancy between atmospheric Hg concentrations derived from PASs and discontinuous active measurements should be further investigated in the future.Graphical

Biogenic volatile organic compounds in forest therapy base: A source of air pollutants or a healthcare function?

Air pollution poses a significant threat to public health, while biogenic volatile organic compounds (BVOCs) play a crucial role in both aspects. However, the unclear relationship between BVOCs and air pollutants in the under-canopy space limits the accuracy of air pollution control and the exploitation of forest healthcare functions. To clarify the variation of BVOCs in forest therapy bases, and their impacts on ozone (O3) and fine particulate matter (PM2.5) at nose height, total VOCs (TVOCs) in the forest were collected during typical sunny days, while air pollutants and meteorological factors were observed simultaneously. The results showed that the branch-level emissions of P. tabuliformis were dominated by healthcare-effective monoterpenoids, with only α-pinene having relative air concentrations of over 5 % in forest air samples. The correlation between concentrations of under-canopy TVOCs and emission rates of BVOCs from P. tabuliformis was weak (p > 0.09) in all seasons. However, the correlation between concentrations of TVOCs and the concentrations of O3 and PM2.5 showed clear seasonal differences. In spring, TVOCs only showed a significant negative correlation with PM2.5 in the forest (p < 0.01). In summer and autumn, TVOCs were significantly negatively correlated with both O3 (p < 0.001) and PM2.5 (p < 0.01). Specifically, the negative linear relationships were more pronounced for O3 and oxygenated VOCs in autumn (R2 = 0.40, p < 0.001) than for other relationships. The relationship between air pollutant concentrations inside and outside the forest also showed significant seasonal differences, generally characterized by a weaker correlation between them during seasons of strong emissions. Therefore, BVOCs in coniferous forests are health functions as they can provide healthcare effects and mitigate the concentration of air pollutants in the forest, and the establishment of forest therapy bases in rural areas with low NOx can be a sensible approach to promote good health, well-being, and sustainable development.

A Comparative Study on Microbial Air Quality of Radiology and Patient Waiting Rooms of a Full-Equipped Hospital in Aydın Province

Every year many patients die due to hospital-acquired infections. These infections also put the lives of healthcare workers at risk. Additionally, hospitals are one of the main reservoirs of antimicrobial resistance. In this study, the effect of X-rays on species diversity and functions and antimicrobial resistance were observed. Metagenome analysis was performed on air samples taken from the x-ray room (radiation exposure) and the waiting room (non-radiation area) to examine whether the radiation affected the species present in the air. The diversity of microorganisms was analysed based on phylum, genus, and species levels. Functional profiling and resistance screening were also performed. X-ray radiation was found to have a major effect at the phylum level. It was observed that Proteobacteria species almost dominated the microbiome in the x-ray room (99%) while Actinobacteria species dominated the microbiome in the waiting room (84%). No significant differences were observed between the two areas in functional profiling. A total of thirty-eight functions were observed, twenty-four of which were overlapping. Antimicrobial resistance was not as diverse as expected. Only beta-lactam, penicillin, tetracycline, and lincomycin resistance genes were present (2364 reads belonging to four different genes). According to the results, it was observed that X-rays affected the air microbiome, as expected. A decrease in the number of microorganisms was expected, but it was also observed that the dominant microorganism types changed. On the other hand, no significant difference was found in terms of functional profiling and no significant antimicrobial resistance was observed.

Monitoring and analysis of pathogenic microorganisms and resistance genes.

The objectives are to improve the rapid identification method of microbial risk and cut off the route of transmission of resistance genes. When new pathogenic microorganisms are found, intervention can be carried out as early as possible to identify the risk of potential pathogen transmission, and timely cut off the transmission route. Hospital air samples were collected to analyse the distribution of environmental pathogenic microorganisms and the characteristics of ARGs resistance genes. The air samples were collected from 12 sampling sites in the Affiliated Hospital of Yangzhou University. In the infusion room, general ward and intensive care unit, no significant difference was found in microorganisms, and no significant difference was found in microbial resistance genes. There were some differences in resistance genes between east and west districts. Combined with the detection of pathogenic microorganisms and resistance genes in our hospital, it is necessary to improve the daily disinfection measures such as air conditioning and fresh air equipment, cut off the infection route, block the transmission of resistance genes, and monitor pathogens and resistance genes in airborne diseases.

Atmospheric constraints on changing Arctic CH4 emissions

Rapid warming in the Arctic has the potential to release vast reservoirs of carbon into the atmosphere as methane (CH4) resulting in a strong positive climate feedback. This raises the concern that, after a period of near-zero growth in atmospheric CH4 burden from 1999 to 2006, the increase since then may be in part related to increased Arctic emissions. Measurements of CH4 in background air samples provide useful, direct information to determine if Arctic CH4 emissions are increasing. One sensitive first-order indicator for large emission change is the Interpolar Difference, that is the difference in surface atmospheric annual means between polar northern and southern zones (53°–90°), which has varied interannually, but did not increase from 1992 to 2019. The Interpolar Difference has increased moderately during 2020–2022 when the global CH4 burden increased significantly, but not yet to its peak values in the late-1980s. For quantitative assessment of changing Arctic CH4 emissions, the atmospheric measurements must be combined with an atmospheric tracer transport model. Based on multiple studies including some using CH4 isotopes, it is clear that most of the increase in global atmospheric CH4 burden is driven by increased emissions from microbial sources in the tropics, and that Arctic emissions have not increased significantly since the beginning of our measurement record in 1983 through 2022.

Health risk assessment of occupational exposure to heavy metals among green space workers in Iran.

Exposure to heavy metals can result in various adverse health effects. Tehran is rated as one of the world's most polluted cities. Green space workers are continuously exposed to such pollutants in this city. Thus, this study aimed to estimate the health risks caused by exposure to heavy metals among green space workers. Eighty-eight workers and office personnel in two regions with different air quality levels were chosen for sampling. Air samples were collected using the NIOSH-7300 method and analyzed using an Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) instrument. The hazard quotient (HQ) and the lifetime cancer risk (LTCR) were calculated to assess carcinogenic and non-carcinogenic risk levels. The results revealed that the rank order of heavy metals was determined as Zn, Pb, Mn, Ni, Co, and Cd. Workers were subjected to higher concentrations of Ni, Pb, Zn, and Co than office personnel. Furthermore, the Cd, Co, and Zn exposure levels stood significantly higher in region 6 than in region 14. Non-carcinogenic risk levels for all participants fell within the acceptable range. Moreover, no employee had a carcinogenic risk level within the acceptable range when exposed to Cd. Also, 2.3% of individuals demonstrated Ni's acceptable carcinogenic risk level. Owing unacceptable risk levels, proper interventions are required to minimize occupational exposure to heavy metals. These interventions include optimizing shift schedules, using personal protective equipment, and conducting regular health assessments.

Effects of Speleotherapy on Aerobiota: A Case Study from the Sežana Hospital Cave, Slovenia

Speleotherapy is one of the non-pharmacological methods for the treatment and rehabilitation of patients with chronic respiratory diseases, especially those with chronic obstructive pulmonary disease (COPD) and asthma. On the one hand, one of the alleged main advantages of speleotherapeutic caves is the low microbial load in the air and the absence of other aeroallergens, but on the other hand, due to the lack of comprehensive air monitoring, there is little information on the pristine and human-influenced aerobiota in such environments. The aim of this study was to assess the anthropogenic effects of speleotherapy on the air microbiota and to investigate its potential impact on human health in Sežana Hospital Cave (Slovenia). From May 2020 to January 2023, air samples were collected in the cave before and after speleotherapeutic activities using two different volumetric air sampling methods—impaction and impingement—to isolate airborne microbiota. Along with sampling, environmental data were measured (CO2, humidity, wind, and temperature) to explore the anthropogenic effects on the aerobiota. While the presence of patients increased microbial concentrations by at least 83.3%, other parameters exhibited a lower impact or were attributed to seasonal changes. The structure and dynamics of the airborne microbiota are similar to those in show caves, indicating anthropization of the cave. Locally, concentrations of culturable microorganisms above 1000 CFU/m3 were detected, which could have negative or unpredictable effects on the autochthonous microbiota and possibly on human health. A mixture of bacteria and fungi typically associated with human microbiota was found in the air and identified by MALDI-TOF MS with a 90.9% identification success rate. Micrococcus luteus, Kocuria rosea, Staphylococcus hominis, and Staphylococcus capitis were identified as reliable indicators of cave anthropization.

Nontarget Identification of Novel Organophosphorus Flame Retardants and Plasticizers in Indoor Air and Dust from Multiple Microenvironments in China.

The indoor environment is a typical source for organophosphorus flame retardants and plasticizers (OPFRs), yet the source characteristics of OPFRs in different microenvironments remain less clear. This study collected 109 indoor air samples and 34 paired indoor dust samples from 4 typical microenvironments within a university in Tianjin, China, including the dormitory, office, library, and information center. 29 target OPFRs were analyzed, and novel organophosphorus compounds (NOPs) were identified by fragment-based nontarget analysis. Target OPFRs exhibited the highest air and dust concentrations of 46.2-234 ng/m3 and 20.4-76.0 μg/g, respectively, in the information center, where chlorinated OPFRs were dominant. Triphenyl phosphate (TPHP) was the primary OPFR in office air, while tris(2-chloroethyl) phosphate dominated in the dust. TPHP was predominant in the library. Triethyl phosphate (TEP) was ubiquitous in the dormitory, and tris(2-butoxyethyl) phosphate was particularly high in the dust. 9 of 25 NOPs were identified for the first time, mainly from the information center and office, such as bis(chloropropyl) 2,3-dichloropropyl phosphate. Diphenyl phosphinic acid, two hydroxylated and methylated metabolites of tris(2,4-ditert-butylphenyl) phosphite (AO168), and a dimer phosphate were newly reported in the indoor environment. NOPs were widely associated with target OPFRs, and their human exposure risk and environmental behaviors warrant further study.

Fungible, Multiyear Solar Thermochemical Energy Storage Demonstrated via the Cobalt Oxide Cycle

Abstract We present a proof of concept demonstration of solar thermochemical energy storage on a multiple year time scale. The storage is fungible and can take the form of process heat or hydrogen. We designed and fabricated a 4-kW solar rotary drum reactor to carry out the solar-driven charging step of solar thermochemical storage via metal oxide reduction–oxidation cycles. During the summer of 2019, the solar reactor was operated in the Valparaiso University solar furnace to effect the reduction of submillimeter cobalt oxide particles in air at approximately 1000∘C. A particle collection system cooled the reduced particles rapidly enough to maintain conversions of 84–94% for feed rates of 2.9−60.8gmin−1. The solar-to-chemical storage efficiency, defined as the enthalpy of the reduction reaction at 1000∘C divided by the solar energy input, reached 20%. Samples of the reduced cobalt oxide particles were stored in vials in air at room temperature for more than 3 years. The stored solar energy was released by reoxidizing samples in air in a benchtop reactor and by electrochemically reoxidizing samples to produce H2. Measurements of the oxygen uptake by the reduced metal oxide confirm its promise as a medium to store and dispatch solar energy over long durations. Linear sweep voltammetry and bulk electrolysis demonstrate the promise of H2 production at 0.55 V relative to the normal hydrogen electrode, 0.68 V below the 1.23 V potential required for conventional electrolysis.

Comparison of Three Air Sampling Methods for the Quantification of Salmonella, Shiga-toxigenic Escherichia coli (STEC), Coliforms, and Generic E. coli from Bioaerosols of Cattle and Poultry Farms

Recent fresh produce outbreaks potentially associated with bioaerosol contamination from animal operations in adjacent land highlighted the need for further study to better understand the associated risk. The purpose of this research was to evaluate three sampling methods for quantifying target bacterial bioaerosols from animal operations. A dairy cattle and poultry farm located in Georgia, U.S. were visited six times each. Air was collected for 10 min using: 2-stage Andersen impactor with and without mineral oil overlay and impingement samplers. Sampling devices were run concurrently at 0.1, 1, and 2 m heights (n = 36). Andersen samplers were loaded with CHROMagar™ Salmonella, CHROMagar™ STEC, or Brilliance™ coliforms/E. coli. The impingement sampler contained buffered peptone water (20 mL) which was vacuum filtered through a 0.45 µm filter and placed onto the respective media. Plates were incubated at 37 ℃ for 48 h. PCR confirmation followed targeting ttr for Salmonella and stx1, stx2, and eae genes for STEC. No significant differences were found among methods to quantify coliforms and E. coli. Salmonella and STEC bioaerosols were not detected by any of the methods (Limit of detection: 0.55 log CFU/m3). E. coli bioaerosols were significantly greater in the poultry (2.76–5.00 log CFU/m3) than in the cattle farm (0.55–2.82 log CFU/m3) (p < 0.05), and similarly distributed at both stages in the Andersen sampler (stage 1:>7 μm; stage 2: 0.65–7 μm particle size). Sampling day did not have a significant effect on the recovery of coliforms/E. coli bioaerosols in the poultry farm when samples were taken at the broiler house exhaust fan (p > 0.05). A greater and constant emission of coliforms and E. coli bioaerosols from the poultry farm warrants further investigation. These data will help inform bioaerosol sampling techniques which can be used for the quantification of bacterial foodborne pathogens and indicator organisms for future research.

Exposure and health risk assessment of volatile organic compounds among drivers and passengers in long-distance buses

Exposure to volatile organic compounds (VOCs) such as benzene, toluene, ethylbenzene, xylene, and formaldehyde from long-distance buses has been reported to adversely affect human health. This study investigates the concentrations of these five VOCs and evaluates their health risks to drivers and passengers on board. Ten trips from Taipei to Taichung were performed during the warm and cold seasons of 2021–2022. Two locations inside the bus were established to collect air samples by a 6-liter canister for drivers and passengers. Exposure concentrations of benzene, toluene, ethylbenzene, and xylene were analyzed via gas chromatography with a flame ionization detector and the formaldehyde concentration was monitored using a formaldehyde meter. Subsequently, a Monte Carlo simulation was conducted to evaluate the carcinogenic and non-carcinogenic risks of the five VOCs. Formaldehyde emerged as the highest detected compound (9.06 ± 3.77 μg/m3), followed by toluene (median: 6.11 μg/m3; range: 3.86–14.69 μg/m3). In particular, formaldehyde was identified to have the significantly higher concentration during non-rush hours (10.67 ± 3.21 μg/m3) than that during rush hours (7.45 ± 3.41 μg/m3) and during the warm season (10.71 ± 2.97 μg/m3) compared with that during the cold season (7.41 ± 4.26 μg/m3). Regarding non-carcinogenic risks to drivers and passengers, the chronic hazard indices for these five VOCs were under 1 to indicate an acceptable risk. In terms of carcinogenic risk, the median risks of benzene and formaldehyde for drivers were 2.88 × 10−6 (95% confidence interval [CI]: 2.11 × 10−6 – 5.13 × 10−6) and 1.91 × 10−6 (95% CI: 4.54 × 10−7 – 3.44 × 10−6), respectively. In contrast, the median carcinogenic risks of benzene and formaldehyde for passengers were less than 1 × 10−6 to present an acceptable risk. This study suggests that benzene and formaldehyde may present carcinogenic risks for drivers. Moreover, the non-carcinogenic risk for drivers and passengers is deemed acceptable. We recommended that the ventilation frequency be increased to mitigate exposure to VOCs in long-distance buses.

Total Suspended Particulate Matter (TSP)-Bound Carbonaceous Components in a Roadside Area in Eastern Indonesia

To evaluate carbonaceous components in the ambient air in the eastern region of Indonesia, 35 Total Suspended Particulate Matter (TSP) samples were collected on four characteristic roadsides on Sultan Alauddin Street, in Makassar City, using a high-volume air sampler. The average TSP concentration was 279.7 μg/m3, which exceeded both the National Ambient Air Quality Standard (NAAQS) of Indonesia and the World Health Organization (WHO) standards. The highest concentration reached 838.6 μg/m3 in the GR (gravel) site, which had the highest number of vehicles and was near a U-turn. TSP concentration was higher during peak hours (morning and late afternoon) than off-peak hours (noon). The main component of the total carbon (TC) fraction was organic carbon (OC), which showed a strong correlation with elemental carbon (EC) (r values for the morning, noon, and late afternoon were 0.89, 0.87, and 0.97, respectively), indicating that the carbon components were derived from common sources. TSP had a strong correlation with carbon components, except for char-EC. OC vs. soot-EC and EC vs. soot-EC also correlated well, suggesting the dominant influence of vehicle exhaust emissions. Non-exhaust emissions had a slight influence during peak hours, particularly at the GR site.

Correlation between Aerosol Particulates, Carcass Dirtiness, and Hygiene Indicators of Bovine Carcasses in the Abattoir Environment: Results of a Study in Italy

The objective of this study was to demonstrate the possible correlation of visible carcass contamination and abattoir aerosol quality with microbial hygiene criteria. A total of 279 bovine carcasses were analyzed on 23 different working days. The aerobic colony count and total coliforms on the carcasses were calculated together with the presence of Escherichia coli. To determine the visible contamination of carcasses, we used a 100 cm2 sheet of transparent, adhesive plastic material, applied to the side of the carcass, to collect all the particles, which were then counted against both black and white backgrounds. The daily particulate index in the abattoir aerosol was determined using an air sampler device. The results showed that aerobic colony counts, which ranged from 1.41 to 2.40 log cfu cm−2, total coliforms (from 0.00 to 0.73 log cfu cm−2), and E. coli presence (from 0.00% to 60% of the sampled carcasses per day) are not correlated with the carcasses’ visual dirtiness or the aerosol quality. The factor analysis showed a correlation between the three groups of variables investigated: group 1, representing “aerosol quality”, group 2, representing the “microbiology of the carcass”, and group 3, the “visual dirtiness of the carcass”. Thus, even though microbiology analysis is useful in diagnosing the microorganisms which the official veterinarian is unable to detect during the post-mortem inspection, it is ineffective in evaluating slaughtering procedures. Aerosol monitoring and the visual classification of carcass dirtiness, instead, could provide good indications of the slaughtering process and the quality of the abattoir environment, and guarantee control of manufacturing practices, protecting both animals’ and operators’ health.

Capturing pollution characteristics in different air mass experimentally using an automatically directional air sampler

Pollution characteristics in air masses from different directions could be dissimilar and consequently have distinct impacts on human health; however, available studies did not provide separated results of pollution characteristics for air from different directions in one experiment when using traditional air samplers. Here, an Automatically Directional Air Sampler (ADAS) is developed and evaluated aiming at providing a new sampling approach for capturing and comparing hazardous air pollutants in different air masses. PM2.5 and particulate polycyclic aromatic hydrocarbons (PAHs, including 16 priority and 13 non-priority ones) are measured as targeted air pollutants in evaluating the performance of this new device. The time-weighted averages of pollution levels over the whole sampling duration using the ADAS were close to that using a traditional air sampler, but the former clearly captured distinct pollution characteristics such as pollution levels, composition profiles and potential sources of PAHs in air masses from different directions. The new device also provided an estimate of relative contributions of air pollution in different air trajectories. In the study site, air mass from the west had relatively high pollution levels, at 6.83 ng/m3, but contributed to only 14% of the averaged 0.75 ng/m3 during the sampling period. Sampling absorbents or channels can be modified in future to collect other air pollutants of interest. The experimental evidences of different pollution characteristics in different trajectories are important in identifying priority risk sources and developing pollution control strategies more efficiently.

Assessment of some air pollutants in the Sanctuary of the Beata Vergine dei Miracoli (Saronno, Italy) and first evaluation of a new axial passive sampler for nitrogen dioxide

In the present study the concentration of some air pollutants (nitrogen dioxide, sulphur dioxide, hydrogen sulphide, ammonia and BTEX, i.e. benzene, toluene, ethylbenzene and xylene) was monitored inside and outside the Sanctuary of the Beata Vergine dei Miracoli (Saronno, Italy) by passive air sampling (using radial samplers), during two sampling periods in 2022 (April 27-May 11 and May 11-May 25). Concurrently, particulate matter (PM10 and PM2.5) concentration was determined by using sensors based on laser scattering technology. Moreover, we took advantage of the location of this sanctuary (proximity to an air monitoring central unit) to evaluate the performance of a new axial-type sampler for nitrogen dioxide. Sulphur dioxide concentration was in the range 0.8–3.1 µg/m3, with outdoor values higher than indoor ones, whereas no detectable concentrations of hydrogen sulphide were found (<0.1 µg/m3). A different trend was observed for ammonia, where indoor concentrations were higher than outdoor ones (3.6–5.5 vs 2.7–3.1 µg/m3). Among BTEX, only for benzene statistical differences (p-value < 0.05) between the indoor and outdoor concentrations were found, suggesting additional indoor sources for this hydrocarbon. Toluene results as the most abundant among these hydrocarbons (1.7–2.3 µg/m3) in outdoor environments, whereas, in indoor environments, benzene has the higher concentration (6–9 µg/m3). The indoor concentrations of NO2 (15.4–22.2 µg/m3 for radial samplers and 48–60 µg/m3 for axial samplers) are not only much higher than the recommended limit values to guarantee proper conservation of artefacts (5 µg/m3), but also close to the values for human health preservation (40 µg/m3), suggesting the need of proper strategy to improve indoor air quality inside the Sanctuary. The preliminary results obtained for the new axial-type sampler for nitrogen dioxide are very encouraging, given the closeness of the obtained concentration data to those measured by monitoring central unit, even though further experiments will have to be carried out to validate this sampler.

Passive Air Sampling Networks Combined with Multivariate Statistics Reveal Widespread Non-Aroclor Polychlorinated Biphenyl Sources to the Canadian Atmosphere

Passive Air Sampling Networks Combined with Multivariate Statistics Reveal Widespread Non-Aroclor Polychlorinated Biphenyl Sources to the Canadian Atmosphere