Airborne Samples Research Articles

Prerequisite for Imputing Non-detects among Airborne Samples in OSHA's IMIS Databank: Prediction of Sample's Volume.

The US Integrated Management Information System (IMIS) contains workplace measurements collected by Occupational Safety and Health Administration (OSHA) inspectors. Its use for research is limited by the lack of record of a value for the limit of detection (LOD) associated with non-detected measurements, which should be used to set censoring point in statistical analysis. We aimed to remedy this by developing a predictive model of the volume of air sampled (V) for the non-detected results of airborne measurements, to then estimate the LOD using the instrument detection limit (IDL), as IDL/V. We obtained the Chemical Exposure Health Data from OSHA's central laboratory in Salt Lake City that partially overlaps IMIS and contains information on V. We used classification and regression trees (CART) to develop a predictive model of V for all measurements where the two datasets overlapped. The analysis was restricted to 69 chemical agents with at least 100 non-detected measurements, and calculated sampling air flow rates consistent with workplace measurement practices; undefined types of inspections were excluded, leaving 412,201/413,515 records. CART models were fitted on randomly selected 70% of the data using 10-fold cross-validation and validated on the remaining data. A separate CART model was fitted to styrene data. Sampled air volume had a right-skewed distribution with a mean of 357 l, a median (M) of 318, and ranged from 0.040 to 1868 l. There were 173,131 measurements described as non-detects (42% of the data). For the non-detects, the V tended to be greater (M = 378 l) than measurements characterized as either 'short-term' (M = 218 l) or 'long-term' (M = 297 l). The CART models were complex and not easy to interpret, but substance, industry, and year were among the top three most important classifiers. They predicted V well overall (Pearson correlation (r) = 0.73, P < 0.0001; Lin's concordance correlation (rc) = 0.69) and among records captured as non-detects in IMIS (r = 0.66, P < 0.0001l; rc = 0.60). For styrene, CART built on measurements for all agents predicted V among 569 non-detects poorly (r = 0.15; rc = 0.04), but styrene-specific CART predicted it well (r = 0.87, P < 0.0001; rc = 0.86). Among the limitations of our work is the fact that samples may have been collected on different workers and processes within each inspection, each with its own V. Furthermore, we lack measurement-level predictors because classifiers were captured at the inspection level. We did not study all substances that may be of interest and did not use the information that substances measured on the same sampling media should have the same V. We must note that CART models tend to over-fit data and their predictions depend on the selected data, as illustrated by contrasting predictions created using all data vs. limited to styrene. We developed predictive models of sampled air volume that should enable the calculation of LOD for non-detects in IMIS. Our predictions may guide future work on handling non-detects in IMIS, although it is advisable to develop separate predictive models for each substance, industry, and year of interest, while also considering other factors, such as whether the measurement evaluated long-term or short-term exposure.

Multistage Optimization of Occupational Safety for Cotton Fabric Screen Printing Press Operators

ABSTRACT The aim of this article is to conduct an analysis leading to the optimization of industrial safety related to the use of a cotton fabric automatic screen printing press. The author’s multistage algorithm, i.e., the analysis-synthesis-minimization procedure, brings effective solutions to the issue in question. There are several risk factors at the printing press workstation and its environment, which are identified by employee surveys, scorecards and airborne samples testing. The risks are visualized by the fishbone/Ishikawa diagram. In accordance with the Fine–Kinney method, a set of 70 scorecards assessing occupational risk is applied to support the identification of critical hazards, which is next re-analyzed using the Analytic Hierarchy Process (AHP). Hierarchically assessed risk factors related to the use of a printing press are easy to be minimized by organizational and technical solutions which are intended to be implemented at the workplace.

Rainfall effects on vertical profiles of airborne fungi over a mixed land-use context at the Brazilian Atlantic Forest biodiversity hotspot

Whilst fungi are a large fraction of primary biological aerosol particles (PBAPs) and their impact on global climate has been widely recognised, few studies have empirically assessed fungal vertical profiles and diversity relating those with rainfall. Here, we show the results of fungal PBAPs before and after a rainfall event during a fieldwork campaign using a hot-air balloon over a mixed land-use context at the Brazilian Atlantic Forest biodiversity hotspot. Four flights of c. 1 hour each were performed in the early morning from 8th until 11th of March 2022, and data were collected at three sampling heights (0, 150 and 300 m). Rainfall estimation using IMERG data indicated the precipitation event was of 15–20 mm and ERA5/ECMWF data highlighted that most of the airborne samples were taken above the boundary layer height. After the rainfall, the concentration of fungal spores at the ground level remained unchanged, whereas it was reduced to between 2- and 2.5-fold for the 150 and the 300 m heights, respectively. This was also accompanied by a reduction in the number of Pink-CFU, indicating a major drop in fungal PBAPs at higher altitudes associated with the rain. In addition, total spore concentration indicated Cladosporium sp. as dominant at all sampling heights, accounting for more than 80% of all spores, whereas Aspergillus/Penicillium-like represented less than 20%. Our results show the effects of rainfall and altitude on the concentration of fungal PBAPs, indicating how wet removal impacts fungi vertical profiles which has knock-on-effects on cloud and precipitation formation.

A Flow-through Passive Sampler for Microplastics in Air.

Microplastics (MP) in air have attracted increasing attention because of their ubiquitous presence. Accurate atmospheric concentrations of MP are essential for evaluating their capacity for long-range transport and for assessing human inhalation risk. In order to sample airborne MP in locations with limited power supply, we adapted a flow-through passive sampler by placing a glass fiber filter in the inner sampling tube. To test the new sampler's performance under field conditions, two sizes of the flow-through sampler (with diameters of 20 and 10 cm) and a conventionally pumped high-volume air sampler were co-deployed on the Lhasa campus of the Institute of Tibetan Plateau Research. Accurate sampling volumes could be estimated from a relationship between wind speeds recorded outside and inside of the flow-through sampler. Atmospheric concentrations and compositions of MP that compared favorably with those obtained by active sampling indicate that the larger version of the flow-through passive sampler can provide reproducible and quantitative information on atmospheric MP at sites with limited or unreliable power supply. This capability should be useful in large-scale and high-temporal resolution air monitoring networks for MP.

DNA breaks evaluation of two water-based metalworking fluids by an occupational exposure design

Thermal degradation of water-based metalworking fluids (MWFs) produces carcinogen by-products. Since different additives have been used to eliminate hazardous material, the carcinogenic potential of two water-based MWFs was investigated in the lung epithelial cell line (A549). Two MWF types were studied in pure and on-used. The chemical content of all samples was assessed by gas chromatography–mass spectrometry (GC-MS). DNA damage of samples was evaluated in the doses range of 0.05–0.8 mg by comet assay. Comet images were analyzed with Open comet software. Amine borate and ethanolamine were found in B and C fluids respectively. Pyridazine compound by the potency of nitrosamine production was found in on-used C fluid. After using MWFs in the metal processing, a polycyclic component with bore central groups was produced in on-used B fluid. DNA damage of on-used fluid with boron component occurred at a level lower than ethyl amine-containing fluid. Moreover, the genotoxicity of air samples in B fluid was higher than C airborne samples significantly. More careful management have to be considered for the replacement of amine corrosion inhibitors with boron-containing chemical in MWFs. In conclusion design of a plan was required for the control of high-risk chemicals in the metal processing industry.

Assessing Environmental Mitigation Strategies in Controlled Cage-Free Aviary Housing Systems: Effect on Air Quality and Bioaerosols

Highlights Three mitigation strategies were tested in experimental chambers fitted as small-scale aviaries. Particle monitor and high-flow air samplers were used to sample airborne dust (PM) and bioaerosols. Oil emulsion sprinkling on the litter surface of aviaries was effective in reducing PM emissions in experimental chambers. Abstract. Alternative housing systems for laying hens are gradually replacing battery cages. Though these systems provide more space per animal and enrichments, higher concentrations of ammonia and airborne dust have been reported in those environments. In this project, three environmental control strategies and a control condition were tested in twelve experimental chambers fitted as small-scale aviaries. The experiment was conducted during three periods spanning 18 weeks, during which PM and bioaerosols were sampled in each chamber in three separate sampling campaigns. Emissions of PM, culturable bacteria and molds, total bacteria, Penicillium, and Aspergillus molds and selected fecal indicators (Campylobacter coli, Campylobacter jejuni, Clostridium perfringens, Escherichia coli, Enterococcus spp., Salmonella spp.) were assessed in each experimental chamber. Strategies that included oil emulsion sprinkling on litter surface were effective at reducing PM emissions, while no significant effect (p &amp;gt; 0.05) was observed on ammonia emissions, and the effect on bioaerosol was variable under the evaluated conditions. Keywords: Airborne dust, Aviaries, Bioaerosol, Laying hen alternative housing, Mitigation.

Bacterial Community Characteristics Shaped by Artificial Environmental PM2.5 Control in Intensive Broiler Houses.

Multilayer cage-houses for broiler rearing have been widely used in intensive Chinese farming in the last decade. This study investigated the characteristics and influencing factors of bacterial communities in the PM2.5 of broiler cage-houses. The PM2.5 samples and environmental variables were collected inside and outside of three parallel broiler houses at the early, middle, and late rearing stages; broiler manure was also gathered simultaneously. The bacterial 16S rRNA sequencing results indicated that indoor bacterial communities were different from the outdoor atmosphere and manure. Furthermore, the variations in airborne bacterial composition and structure were highly influenced by the environmental control variables at different growth stages. The db-RDA results showed that temperature and wind speed, which were artificially modified according to managing the needs for broiler growth, were the main factors affecting the diversity of dominant taxa. Indoor airborne and manurial samples shared numerous common genera, which contained high abundances of manure-origin bacteria. Additionally, the airborne bacterial community tended to stabilize in the middle and late stages, but the population of potentially pathogenic bacteria grew gradually. Overall, this study enhances the understanding of airborne bacteria variations and highlighted the potential role of environmental control measures in intensive farming.

Environmental monitoring for invasive fungal pathogens of ʽŌhiʽa (Metrosideros polymorpha) on the Island of Hawaiʽi

The invasive rust Austropuccina psidii was detected in the Hawaiian Islands in 2005 and has become widely established throughout the archipelago in both native and introduced species of Myrtaceae. Initial predictions about the impacts of the fungus on native ʽōhiʽa lehua (Metrosideros polymorpha), a keystone native tree, have not materialized, but there is ongoing concern that introductions of new genotypes of the fungus could lead to widespread mortality with catastrophic effects on native ecosystems. By contrast, two recently emergent Ascomycete pathogens, Ceratocystis lukuohia (Ceratocystis wilt of ‘ōhi‘a) and C. huliohia (Ceratocystis canker of ‘ōhi‘a), collectively known to cause Rapid ʽŌhiʽa Death (ROD), are causing significant mortality in native forests on Hawaiʻi and Kauaʻi Islands, but pathways of spread are still incompletely understood. We used a network of passive environmental samplers for collecting windblown urediniospores of Austropuccina to evaluate the effectiveness of environmental monitoring to detect seasonal and landscape-scale differences in airborne propagules of this rust on Hawai`i Island. The samplers were also used to determine if windborn ambrosia beetle frass or spores of Ceratocystis can spread long distances. We found frequent detections and regional and seasonal differences in numbers of samplers that were positive for urediniospores of Austropuccinia, but little evidence of long-distance airborne dispersal of the ROD-causing fungi. The simple, inexpensive platform for sampling airborne fungal spores that we used may have value as a monitoring tool for detecting spread of airborne fungal pathogens, evaluating habitats for suitability for restoration efforts, and for detecting new pathogen introductions, particularly new Austropuccinia genotypes both in Hawaiʻi and other parts of the world.

Bacteriological assessments of indoor air in the staff quarters of a tertiary institution in Benin City, Nigeria

Indoor air contains large number of airborne microorganisms such as bacteria and fungi and their estimation is important for use as index of cleanliness for any particular environment and to determine the relation they bear on human health. This study was aimed at determining the bacteriological air quality of the living rooms in some selected Staff Quarters in University of Benin and University of Benin Teaching Hospital. The airborne bacterial loads of indoor air in the living rooms of Twelve (12) Staff Quarters in University of Benin and University of Benin Teaching Hospital both in Benin City were determined using the Settle Plate methods. The houses were categorized as Apartment 1 which represents University of Benin Junior Staff Quarters (JSQ), Apartment 2 which represents University of Benin Teaching Hospital Quarters, and Apartment 3 which represents University of Benin Senior Staff Quarters (SSQ). The living rooms were sampled twice a month between April, 2017 and September, 2017. The airborne samples were studied using standard microbiological methods and Polymerase Chain Reaction and 16S rRNA techniques were used for the gene sequencing. The antibiotic susceptibility pattern and plasmid profile of the characterized airborne bacterial isolates were evaluated using spread plate and agarose gel electrophoresis methods. The temperature and relative humidity of the indoor air environment in the sampled areas in the living rooms were determined using the thermometer and hygrometer respectively. The mean indoor temperature and relative humidity for Apartments 1, 2 and 3 ranged from 26.10 ± 1.190C to 31.20 ± 0.870C and 81 ± 2.70% to 87 ± 1.89% respectively. The mean indoor airborne bacterial counts in Apartment 1 and Apartment 3 ranged between 1.00 x 103 ± 0cfu/m3 to 4.42 x 103 ± 1.42cfu/m3 and 1.09 x 103 ± 0.09cfu/m3 to 5.17 x 103 ± 3.17cfu/m3 respectively. In Apartment 2, the counts ranged from 1.00 x 103 ± 0.00cfu/m3 to 6.99 x 103 ± 4.69cfu/m3. The difference in the airborne bacterial counts obtained in the morning and afternoon period of study in Apartment 1 was statistically significant (P&lt;0.05) while Apartments 2 and 3 showed no significant differences respectively (P&gt;0.05). Ten airborne bacterial isolates were characterized, further characterization by molecular techniques, confirmed them to be identified as Staphylococcus aureus strain S33 R, Bacillus subtilis subsp. strain 168, Oceanobacillus manasiensis strain YD3-56, Streptomyces vietnamensis strain GIM4.0001, Actinosynnema pretiosum strain C-15003, Micrococcus caseolyticus strain 235, Ornithinibacillus composti strain GSS05 and Bacillus ectoiniformans strain NE-14. General and personal hygienic practices are important for healthy living, and living rooms used for close contact interactions and good ventilation.

Measurement report: The Urmia playa as a source of airborne dust and ice-nucleating particles – Part 1: Correlation between soils and airborne samples

Abstract. The emergence of desiccated lake bed sediments and their exposure to wind erosion as a consequence of climate change and drought in arid and semiarid regions of the world poses a growing hazard. Airborne dust originating from such soils can create health and environmental issues due to their high salt content and the presence of toxic elements. The aim of the present study is twofold, namely to investigate the newly emerged playa surfaces of western Lake Urmia (LU) in Iran and their contribution to aerosol in the region by means of physicochemical, mineralogical, and elemental analyses and to study the ice nucleation (IN) activity of both surface-collected soil and airborne dust samples. The playa surfaces created by desiccation of LU on the western shores were mapped and sampled at 130 locations. Soil samples were subjected to physicochemical analyses, and their erodible fraction was determined. Based on these analyses, four highly erodible playa surfaces from the northwest to the south of LU were selected as sites for collection of dust by impaction and soil samples from the uppermost surface. Their particle physicochemical properties (size distribution, elemental and mineralogical composition) were compared with their IN activity determined by emulsion freezing experiments in a differential scanning calorimeter (DSC) in two suspension concentrations of 2 wt % and 5 wt %. The physicochemical soil properties differed significantly between the different playa surfaces, which affects their susceptibility to wind erosion. Sand sheets and sandy salt crusts were the most erodible playa surfaces due to their high sand fraction and low organic matter and clay content, favouring the presence of small aggregates. Mineralogical analyses document the prevalence of quartz, carbonates, and clay minerals, such as kaolinite, palygorskite, and chlorite in all of the samples. The predominant elements in the samples are Ca, Fe, Al, Si, and Na (and in some cases Ba, Sr, and Zn). The correlation between soil and dust samples based on mineralogical composition, elemental enrichment factors, and physicochemical properties confirm that the playa surfaces are the major contributors to dust in the region. IN activity with onset temperatures ranging from 245 to 250 K demonstrates the high potential of dust blown from Urmia playa surfaces to affect cloud properties and precipitation. Freezing onset temperatures and the fraction of heterogeneously frozen droplets in the emulsions reveal variations in IN activity depending on the mineralogical composition of the samples but which are also influenced by organic matter, salinity, and pH. Specifically, IN activity correlates positively with organic matter and clay minerals and negatively with pH, salinity, and (surprisingly) K-feldspar and quartz content. The high wind erodibility and dust production of the LU playa surfaces together with their high IN activity can play an important role in the climate of the region and thus needs careful monitoring and specific attention.

The impact of ventilation rate on reducing the microorganisms load in the air and on surfaces in a room-sized chamber.

Hospital-acquired infections (HAIs) are a global challenge incurring mortalities and high treatment costs. The environment plays an important role in transmission due to contaminated air and surfaces. This includes microorganisms' deposition from the air onto surfaces. Quantifying the deposition rate of microorganisms enables understanding surface contamination and can inform strategies to mitigate the infection risk. We developed and validated a novel Automated Multiplate Passive Air Sampling (AMPAS) device. This enables sequences of passive deposition samples to be collected over a controlled time period without human intervention. AMPAS was used with air sampling to measure the effect of ventilation rate and spatial location on the deposition rate of aerosolized Staphylococcus aureus in a 32 m3 chamber. Increasing the ventilation rate from 3 to 6 ACH results in a reduction of microbial load in the air and on surfaces by 45% ± 10% and 44% ± 32%, respectively. The deposition rate onto internal surfaces λd was calculated as 1.38 ± 0.48 h-1 . Samples of airborne and surface microorganisms taken closer to the ventilation supply showed a lower concentration than close to the extract. The findings support the importance of controlling the ventilation and the environmental parameters to mitigate both air and surface infection risks in the hospital environment.

&lt;b&gt;Evaluation of Environmental Hygiene in Railway Vehicles Using Microbiome Analysis&lt;/b&gt;

To evaluate environmental hygiene, we introduce a microbiome analysis that comprehensively and qualitatively grasps types and proportions of microbial genes on surfaces and airborne samples in railway vehicles. We monitored commuter vehicles using this analysis technology and confirmed that it was possible to grasp the difference in microbiome for each type of equipment. The result of the microbial diversity on each type of equipment showed that floors have different microbiomes, and that equipment touched directly by passengers, such as handrails and straps, have similar microbiomes. The result of estimation analysis of origin of microorganisms indicates that the proportion of human-derived microbiomes tends to be high on handrails and straps.

Bioaerosol Concentration in a Cattle Feedlot in Neuquén, Argentina

There is a global trend toward intensive livestock breeding, which tends to increase the microbial load in the environment as well as the presence of volatile compounds and dust that can cause health issues. Cattle is the major producer of Escherichiacoli (E. coli), a group of foodborne bacteria associated with severe human diseases, and Neuquén province in Argentina has one of the highest rates of uremic hemolytic syndrome incidence in the world. This paper presents the results of two sampling events of E. coli bacteria at 39 sites in La Paisana ranch (LPR), in Añelo (Neuquén), considering locations inside the pens, upwind, and downwind of the feedlot with different time steps, using a Microflow α equipment. The ranch has approximately 600 heads and clean and controlled installations. The field experiment included sampling airborne aerosol deposition and concentration using passive and active methods. Concentrations were also estimated using an atmospheric dispersion model. During the field experiment, counts of up to 2970 CFU/m3 were obtained in the cattle stockyards and up to 111 CFU/m3 at a distance of 100 m.

Environmental DNA reveals diversity and abundance of Alternaria species in neighbouring heterogeneous landscapes in Worcester, UK

Alternaria is a pathogenic and allergenic fungus affecting 400 plant species and 334 million people globally. This study aimed at assessing the diversity of Alternaria species in airborne samples collected from closely located (7 km apart) and heterogeneous sites (rural, urban and unmanaged grassland) in Worcester and Lakeside, the UK. A secondary objective was to examine how the ITS1 subregion varies from ITS2 in Alternaria species diversity and composition. Airborne spores were collected using Burkard 7-day and multi-vial Cyclone samplers for the period 5 July 2016–9 October 2019. Air samples from the Cyclone were amplified using the ITS1and ITS2 subregions and sequenced using Illumina MiSeq platform whereas those from the Burkard sampler were identified and quantified using optical microscopy. Optical microscopy and eDNA revealed a high abundance of Alternaria in the rural, urban and unmanaged sites. ITS1 and ITS2 detected five and seven different Alternaria species at the three sampling sites, respectively. A. dactylidicola, A. metachromatica and A. infectoria were the most abundant. The rural, urban and unmanaged grassland sites had similar diversity (PERMANOVA) of the species due to similarity in land use and proximity of the sites. Overall, the study showed that heterogeneous and neighbouring sites with similar land uses can have similar Alternaria species. It also demonstrated that an eDNA approach can complement the classical optical microscopy method in providing more precise information on fungal species diversity in an environment for targeted management. Similar studies can be replicated for other allergenic and pathogenic fungi.

Development and validation of a method for airborne monoclonal antibodies to quantify workplace exposure

Modern therapy strategies are based on patient-specific treatment where the drug and dose are optimally adapted to the patient's needs. In recent drugs, monoclonal antibodies (mAbs) are increasingly used as active ingredients. Their patient-specific formulations are not part of the pharmaceutical industry’s manufacturing process but are prepared from concentrates by pharmaceutical personnel. During the manufacturing process, however, active pharmaceutical ingredients are released in trace amounts or, in the case of accidents and spills, also in high concentrations. Regardless of the source of entry, mAbs can become airborne, be inhaled, and cause undesirable side-effects such as sensitization. To assess the risk for pharmaceutical personnel, a personal air sampling method was developed and validated for bevacizumab, cetuximab, daratumumab, omalizumab, rituximab and trastuzumab. The method is based on the combination of high-performance liquid chromatography with tandem mass spectrometry (HPLC-MS/MS). The analytical method achieves a limit of detection of 0.30–8.8 ng mL−1, recoveries of 83–96 % (intra-day assay) and 75–89 % (inter-day assay), with no detectable carry-over. A polycarbonate filter proved suitable for sampling airborne monoclonal antibodies, as it achieved 80–104 % recovery across all mAbs. It also showed concentration-independent desorption efficiency. The sampling duration can be up to 480 min without negatively affecting the recovery. MAbs are stable on the polycarbonate filter at 5 °C for 3 days (recovery: 94 % ± 5 %) and at − 20 °C for 14 days (recovery: 97 % ± 4 %). Our method demonstrated that there is a potential for release when handling monoclonal antibodies. However, this can be reduced below the limit of detection by using pressure equalization systems (spikes).

Electrophysiological responses to conspecific odorants in Xenopus laevis show potential for chemical signaling.

The fully aquatic African clawed frog, Xenopus laevis, has an unusual and highly adapted nose that allows it to separately sample both airborne and waterborne stimuli. The function of the adult water nose has received little study, despite the fact that it is quite likely to receive information about conspecifics through secretions released into the water and could aid the frog in making decisions about social and reproductive behaviors. To assess the potential for chemical communication in this species, we developed an in situ electroolfactogram preparation and tested the olfactory responses of adult males to cloacal fluids and skin secretions from male and female conspecifics. We found robust olfactory responses to all conspecific stimuli, with greatest sensitivity to female cloacal fluids. These results open the door to further testing to identify compounds within cloacal fluids and skin secretions that are driving these responses and examine behavioral responses to those compounds. Understanding the role of chemical communication in social and reproductive behaviors may add to our rich understanding of vocal communication to create a more complete picture of social behavior in this species.

Compositional Data Analysis of 16S rRNA Gene Sequencing Results from Hospital Airborne Microbiome Samples.

The compositional analysis of 16S rRNA gene sequencing datasets is applied to characterize the bacterial structure of airborne samples collected in different locations of a hospital infection disease department hosting COVID-19 patients, as well as to investigate the relationships among bacterial taxa at the genus and species level. The exploration of the centered log-ratio transformed data by the principal component analysis via the singular value decomposition has shown that the collected samples segregated with an observable separation depending on the monitoring location. More specifically, two main sample clusters were identified with regards to bacterial genera (species), consisting of samples mostly collected in rooms with and without COVID-19 patients, respectively. Human pathogenic genera (species) associated with nosocomial infections were mostly found in samples from areas hosting patients, while non-pathogenic genera (species) mainly isolated from soil were detected in the other samples. Propionibacterium acnes, Staphylococcus pettenkoferi, Corynebacterium tuberculostearicum, and jeikeium were the main pathogenic species detected in COVID-19 patients’ rooms. Samples from these locations were on average characterized by smaller richness/evenness and diversity than the other ones, both at the genus and species level. Finally, the ρ metrics revealed that pairwise positive associations occurred either between pathogenic or non-pathogenic taxa.

Occupational exposure to metals among battery recyclers in France: Biomonitoring and external dose measurements

In battery-recycling facilities, exposure to trace elements may occur through inhalation of contaminated dust or vapor emanating from the treatment processes. Exposure of battery-recycling workers to lead has been quite well covered in the literature. In contrast, we lack data on exposure to other elements contained in batteries. The aim of this study was to characterize the exposure of French battery recyclers to multiple elements using biomonitoring and airborne measurements. Eighty-six workers participated in the study. Inhalable metal concentrations were determined for personal airborne samples, and total exposure was determined from pre-shift and post-shift urine samples collected during the working week. In both types of sample, a total of 33 trace elements were measured using inductively coupled plasma mass spectrometry. Results showed battery recyclers to be mostly exposed to Cd, Co, Cr, Li, Mn, Ni, and Pb. Administrative and sorting workers were exposed at lower levels than maintenance, treatment, and dismantling workers. Cd, Co, Li, Mn, and Ni were detected at high levels in air samples, especially near the treatment facilities, with airborne cadmium levels of up to 79.4 µg/m3. Urinary sample analysis indicated exposure to Cd and Co, with levels measured at up to 27.6 and 3.34 µg/g of creatinine, respectively. Concentrations were compared to data reported for e-waste recycling companies. The data presented provide valuable information on exposure to trace elements for workers involved in battery-recycling. They also highlight the need to improve both collective and individual protective measures, which were not sufficient in the participating companies.

Assessment of personal inhalation and skin exposures to polymeric methylene diphenyl diisocyanate during polyurethane fabric coating.

Methylene diphenyl diisocyanate (MDI) monomers and polymeric MDI (pMDI) are aromatic isocyanates widely used in the production of polyurethanes. These isocyanates can cause occupational asthma, hypersensitivity pneumonitis, as well as contact dermatitis. Skin exposure likely contributes toward initial sensitization but is challenging to monitor and quantitate. In this work, we characterized workers' personal inhalation and skin exposures to pMDI in a polyurethane fabric coating factory for subsequent health effect studies. Full-shift personal and area air samples were collected from eleven workers in representative job areas daily for 1-2weeks. Skin exposure to hands was evaluated concomitantly with a newly developed reagent-impregnated cotton glove dosimeter. Samples were analyzed for pMDI by liquid chromatography-tandem mass spectrometry. In personal airborne samples, the concentration of 4,4'-MDI isomer, expressed as total NCO, had a geometric mean (GM) and geometric standard deviation (GSD) of 5.1 and 3.3ng NCO/m3, respectively (range: 0.5-1862ng NCO/m3). Other MDI isomers were found at much lower concentrations. Analysis of 4,4'-MDI in the glove dosimeters exhibited much greater exposures (GM: 10ng/cm2) and substantial variability (GSD: 20ng NCO/cm2; range: 0-295ng NCO/cm2). MDI inhalation exposure was well below occupational limits for MDI for all the job areas. However, MDI skin exposure to hands was substantial. These findings demonstrated the potential for substantial isocyanate skin exposure in work settings with very low airborne levels. This exposure characterization should inform future studies that aim to assess the health effects of work exposures to MDI and the effectiveness of protective measures.

Seasonal distribution of PM2.5-bound polycyclic aromatic hydrocarbons as a critical indicator of air quality and health impact in a coastal-urban region of Poland

This study focuses on the inter-seasonal distribution and variability of thirteen native PAHs adsorbed onto respirable PM2.5 fraction collected in a coastal-urban region of northern Poland, in 2019. The backward trajectory analysis and several diagnostic ratios were applied to determine seasonal profiles of PAH congeners and their major sources in airborne samples. The annual cumulative mean value of total PAHs in PM2.5 was 6.92 ± 10.1 ng m−3, varying in the following range: 0.32 ng m−3 (May) – 68.57 ng m−3 (January). Seasonal mass concentrations of total particulate PAHs were ranked as follows: summer (1.27 ng m−3) < spring (4.83 ng m−3) < autumn (6.16 ng m−3) < winter (18.5 ng m−3). Clear seasonal differences in PAH concentrations can be explained by direct impact of local and regional urban/industrial activities, with priority winter contribution of coal combustion in residential and commercial sectors. In addition, for summer measurements the diagnostic ratios indicated that high molecular weight PAHs were mainly derived from vehicle emission and petrochemical industry, while relatively low mass contribution of 4-ring congeners to the total sum of PAHs was attributed to photochemical processing. The analysis of meteorological parameters (temperature, relative humidity) and gaseous precursors (SO2, NO2, NOx, O3 and CO) exhibits their statistically significant correlations with PAHs, indicating local/regional primary emission. The incremental lifetime cancer risk was 1.23 × 10−5, suggesting potential toxicity and carcinogenicity for adult females and males. This study highlights the importance of the implementation of health risk assessment model in urbanized coastal zones.