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The use of alternative diesel fuels has increased due to the demand for renewable energy sources. There is limited knowledge regarding the potential health effects caused by exhaust emissions from biodiesel- and renewable diesel-fueled engines. This study investigates the toxic effects of particulate matter (PM) emissions from a diesel engine powered by conventional petroleum diesel fuel (SD10) and two biodiesel and renewable diesel fuels in vitro. The fuels used were rapeseed methyl ester (RME), soy methyl ester (SME), and Hydrogenated Vegetable Oil (HVO), either pure or as 50% blends with SD10. Additionally, a 5% RME blend was also used. The highest concentration of polycyclic aromatic hydrocarbon emissions and elemental carbon (EC) was found in conventional diesel and the 5% RME blend. HVO PM samples also exhibited a high amount of EC. A dose-dependent genotoxic response was detected with PM from SD10, pure SME, and RME as well as their blends. Reactive oxygen species levels were several times higher in cells exposed to PM from SD10, pure HVO, and especially the 5% RME blend. Apoptotic cell death was observed in cells exposed to PM from SD10, 5% RME blend, the 50% SME blend, and HVO samples. In conclusion, all diesel PM samples, including biodiesel and renewable diesel fuels, exhibited toxicity. [ABSTRACT FROM AUTHOR]

In urban areas, inhalation of fine particles from combustion sources such as diesel engines causes adverse health effects. For toxicity testing, a substantial amount of particulate matter (PM) is needed. Conventional sampling involves collection of PM onto substrates by filtration or inertial impaction. A major drawback to those methodologies is that the extraction process can modify the collected particles and alter their chemical composition. Moreover, prior to toxicity testing, PM samples need to be resuspended, which can alter the PM sample even further. Lastly, the choice of the resuspension medium may also impact the detected toxicological responses. In this study, we compared the toxicity profile of PM obtained from two alternative sampling systems, using in vitro toxicity assays. One system makes use of condensational growth before collection in water in an impinger – BioSampler (CG‐BioSampler), and the other, a Dekati® Gravimetric Impactor (DGI), is based on inertial impaction. In addition, various methods for resuspension of DGI collected PM were compared. Tested endpoints included cytotoxicity, formation of cellular reactive oxygen species, and genotoxicity. The alternative collection and suspension methods affected different toxicological endpoints. The water/dimethyl sulfoxide mixture and cell culture medium resuspended particles, along with the CG‐BioSampler sample, produced the strongest responses. The water resuspended sample from the DGI appeared least toxic. CG‐BioSampler collected PM caused a clear increased response in apoptotic cell death. We conclude that the CG‐BioSampler PM sampler is a promising alternative to inertial impaction sampling. Inhaling air pollution fine particles, such as from diesel engines, poses health risks. Particulate matter (PM) toxicity testing requires a significant amount of PM mass. This study compares PM toxicity in vitro from two sampling systems condensational growth before collection in water in an impinger – BioSampler (CG‐BioSampler) and Dekati® Gravimetric Impactor (DGI). Also, different resuspension methods of DGI collected PM were studied. The employed resuspension methods affected toxicological endpoints differently. [ABSTRACT FROM AUTHOR]

Exhaled breath (EB) contains various volatile organic compounds (VOCs) that can indicate specific biological or pathological processes in the body. Analytical techniques like gas chromatography–mass spectrometry (GC–MS) can be used to detect and measure these exhaled biomarkers. In this study, the objective was to develop a non-invasive method of EB sampling in animals that were awake, as well as to analyze EB for volatile biomarkers specific for chlorine exposure and/or diagnostic biomarkers for chlorine-induced acute lung injury (ALI). To achieve this, a custom-made sampling device was used to collect EB samples from 19 female Balb/c mice. EB was sampled both pre-exposure (serving as internal control) and 30 min after exposure to chlorine. EB was collected on thermal desorption tubes and subsequently analyzed for VOCs by GC–MS. The following day, the extent of airway injury was assessed in the animals by examining neutrophils in the bronchoalveolar lavage fluid. VOC analysis revealed alterations in the EB biomarker pattern post-chlorine exposure, with eight biomarkers displaying increased levels and six exhibiting decreased levels following exposure. Four chlorinated compounds: trichloromethane, chloroacetone, 1,1-dichloroacetone and dichloroacetonitrile, were increased in chlorine-exposed mice, suggesting their specificity as chlorine EB biomarkers. Furthermore, chlorine-exposed mice displayed a neutrophilic inflammatory response and body weight loss 24 h following exposure. In conclusion, all animals developed an airway inflammation characterized by neutrophil infiltration and a specific EB pattern that could be extracted after chlorine exposure. Monitoring EB samples can readily and non-invasively provide valuable information on biomarkers for diagnosis of chlorine-induced ALI, confirming chlorine exposures. [ABSTRACT FROM AUTHOR]

The reactive gases perfluoroisobutene and carbonyl fluoride are highly toxic and difficult to analyze in air. For this paper, the available sampling and analysis methods involving gas chromatography/mass spectrometry were investigated for their potential to give unambiguous identification and quantification of perfluoroisobutene and carbonyl fluoride, for which no such methods exist. Although high concentrations of perfluoroisobutene could be analyzed directly by manual split injection, sorbent sampling followed by thermal desorption GC/MS allowed lower concentrations to be analyzed. However, a significant degradation of perfluoroisobutene observed after thermal desorption analysis inspired the use of derivatization of perfluoroisobutene with 3,4‐dimercaptotoluene. The use of Tenax TA sorbent tubes spiked with 3,4‐dimercaptotoluene and trimethylamine in a molar ratio of 1:8 proved successful for the quantification of a unique perfluoroisobutene derivative, and the method was validated for atmospheres in the range of 0.13–152 ppb with a relative standard deviation of less than 20% and an accuracy of 90%. Although carbonyl fluoride was less stable than perfluoroisobutene, direct analysis was possible at high concentrations but the response was not linear. The 3,4‐dimercaptotoluene derivatization method developed was also applicable for quantification of carbonyl fluoride atmospheres. [ABSTRACT FROM AUTHOR]

Metal oxide fumes form at high temperatures, for instance, during welding or firing ammunition. Inhalation exposure to high levels of airborne metal oxide particles can cause metal fume fever, cardiovascular effects, and lung damage in humans, but the associated underlying pathological mechanisms are still not fully understood. Using human alveolar epithelial cells, vascular endothelial cells, and whole blood model systems, we aimed to elucidate the short‐term effects of well‐characterized metal particles emitted while firing pistol ammunition. Human lung epithelial cells exposed to gunshot smoke particles (0.1–50 μg/ml) produced reactive oxygen species (ROS) and pro‐inflammatory cytokines (interleukin 8 (IL‐8), granulocyte‐macrophage colony‐stimulating factor (GM‐CSF)) that activate and recruit immune cells. Particles comprising high copper (Cu) and zinc (Zn) content activated human endothelial cells via a non‐ROS‐mediated mechanism that triggered immune activation (IL‐8, GM‐CSF), leukocyte adhesion to the endothelium (soluble intercellular adhesion molecule 1 (sICAM‐1)), and secretion of regulators of the acute‐phase protein synthesis (interleukin 6 (IL‐6)). In human whole blood, metal oxides in gunshot smoke demonstrated intrinsic properties that activated platelets (release of soluble cluster of differentiation 40 ligand (sCD40L), platelet‐derived growth factor B‐chain homodimer(PDGF‐BB), and vascular endothelial growth factor A (VEGF‐A)) and blood coagulation and induced concomitant release of pro‐inflammatory cytokines from blood leukocytes that further orchestrate thrombogenesis. The model systems applied provide useful tools for health risk assessment of particle exposures, but more studies are needed to further elucidate the mechanisms of metal fume fever and to evaluate the potential risk of long‐term cardiovascular diseases. Inhalation exposure to metal fumes emitted during pistol firing can cause metal fume fever in humans. The mechanisms behind short‐term toxic responses to metal fumes were investigated in exposure systems using lung epithelium, vascular endothelium, and whole blood. Gunshot smoke particles elicited toxic responses and immune activation in lung epithelial cells, vascular endothelial cells, and white blood cells and activated thrombocytes that orchestrate thrombogenesis, creating a milieu that contributes to metal fume fever and potentially accelerates the development of cardiovascular diseases. [ABSTRACT FROM AUTHOR]

The use of electronic cigarettes (E‐cigs) is rapidly increasing. The latest generation of E‐cigs is highly customizable, allowing for high heating coil temperatures. The aim of this study was to assess the toxic potential of a fourth‐generation E‐cig. Aerosols generated from E‐liquid with (24 mg/mL) and without nicotine, using a fourth‐generation E‐cig, were chemically analysed and compared with cigarette smoke (K3R4F). Human lung epithelial cell lines and distal lung tissue explants were exposed to E‐cig vapour extract (EVE) and cigarette smoke extract for 24 hours and assessed for viability, inflammation, oxidative stress and genotoxicity. E‐cig aerosols contained measurable levels of volatile organic compounds, aldehydes and polycyclic aromatic hydrocarbons, in general, to a much lesser extent than cigarette smoke. Higher levels of certain carbonyls, e.g. formaldehyde, were detected in the E‐cig aerosols. EVEs decreased cell viability of BEAS‐2B cells, whereas little effect was seen in A549 cells and distal lung tissue. The nicotine‐containing EVE caused a greater decrease in cell viability and significant increase in DNA damage than the nicotine‐free EVE. Increased cytotoxicity, reactive oxygen species production and genotoxicity were seen with cells and tissue exposed to cigarette smoke extract compared with EVEs. Although E‐cig aerosols were less toxic than cigarette smoke, it was not benign. Moreover, the EVE containing nicotine was more toxic than the nicotine‐free EVE. More research is needed on the short‐ and long‐term health effects of vaping and the usage of newly emerging E‐cig devices to evaluate better the potential negative effects of E‐cigs on human health. There are few data on the toxic potential of new‐generation electronic cigarette (E‐cig) models. Aerosols generated from a fourth‐generation E‐cig contained volatile organic compounds, aldehydes and polycyclic aromatic hydrocarbons but to a lesser extent than cigarette smoke. E‐cig aerosol extracts were cytotoxic to BEAS‐2B cells, and caused increased cell death and DNA strand breaks when containing nicotine. More research is needed on the short‐ and long‐term health effects of vaping. [ABSTRACT FROM AUTHOR]

Objectives: In an occupational environment, passive sampling could be an alternative to active sampling with pumps for sampling of dust. One passive sampler is the University of North Carolina passive aerosol sampler (UNC sampler). It is often analysed by microscopic imaging. Promising results have been shown for particles above 2.5 µm, but indicate large underestimations for PM2.5. The aim of this study was to evaluate, and possibly improve, the UNC sampler for stationary sampling in a working environment. Methods: Sampling was carried out at 8-h intervals during 24 h in four locations in an open pit mine with UNC samplers, respirable cyclones, PM10 and PM2.5 impactors, and an aerodynamic particle sizer (APS). The wind was minimal. For quantification, two modifications of the UNC sampler analysis model, UNC sampler with hybrid model and UNC sampler with area factor, were compared with the original one, UNC sampler with mesh factor derived from wind tunnel experiments. The effect of increased resolution for the microscopic imaging was examined. Results: Use of the area factor and a higher resolution eliminated the underestimation for PM10 and PM2.5. The model with area factor had the overall lowest deviation versus the impactor and the cyclone. The intraclass correlation (ICC) showed that the UNC sampler had a higher precision and better ability to distinguish between different exposure levels compared to the cyclone (ICC: 0.51 versus 0.24), but lower precision compared to the impactor (PM10: 0.79 versus 0.99; PM2.5: 0.30 versus 0.45). The particle size distributions as calculated from the different UNC sampler analysis models were visually compared with the distributions determined by APS. The distributions were obviously different when the UNC sampler with mesh factor was used but came to a reasonable agreement when the area factor was used. Conclusions: High resolution combined with a factor based on area only, results in no underestimation of small particles compared to impactors and cyclones and a better agreement with the APS's particle size distributions. The UNC sampler had lower precision than the impactors, but higher than the respirable cyclone. The UNC sampler with area factor could be used for PM2.5, PM10 and respirable fraction measurements in this working environment without wind. [ABSTRACT FROM AUTHOR]

Objectives: Dust is generally sampled on a filter using air pumps, but passive sampling could be a cost-effective alternative. One promising passive sampler is the University of North Carolina passive aerosol sampler (UNC sampler). The aim of this study is to characterize and compare the UNC sampler's performance with PM10 and PM2.5 impactors in a working environment. Methods: Area sampling was carried out at different mining locations using UNC samplers in parallel with PM2.5 and PM10 impactors. Two different collection surfaces, polycarbonate (PC) and carbon tabs (CT), were employed for the UNC sampling. Sampling was carried out for 4-25 hours. Results: The UNC samplers underestimated the concentrations compared to PM10 and PM2.5 impactor data. At the location with the highest aerosol concentration, the time-averaged mean of PC showed 24% and CT 35% of the impactor result for PM2.5. For PM10, it was 39% with PC and 58% with CT. Sample blank values differed between PC and CT. For PM2.5, PC blank values were ~7 times higher than those of CT, but only 1.8 times higher for PM10. The blank variations were larger for PC than for CT. Conclusions: Particle mass concentrations appear to be underestimated by the UNC sampler compared to impactors, more so for PM2.5 than for PM10. CT may be preferred as a collection surface because the blank values were lower and less variable than for PC. Future validations in the working environment should include respirable dust sampling. [ABSTRACT FROM AUTHOR]

Numerous studies demonstrated that the use of lead (Pb)-containing ammunition is associated with mainly chronic health problems and also is a burden on the environment and wildlife. Recently, a number of reports showed evidence of undesirable acute health effects related to the use of newly developed Pb-free small-caliber ammunition. In this study, particles from leaded and Pb-free ammunition were collected in liquid collection medium, in a highly controlled chamber, while firing a pistol (9 mm) or a rifle (7.62 × 51 mm). The emitted particles were typically smaller than 4 μm, with the great majority in even smaller size ranges, as shown by gravimetrical analysis and a multistage impactor. Chemical analysis revealed significant differences in content and concentration of several metals in the particles. After administration of the liquids to alveolar and bronchial in vitro cell systems, particles were taken up by the cells; the Pb-free particles displayed higher cytotoxicity (EC50 = 2 μg/cm2) than particles from Pb ammunition. High correlation factors (>0.9) were found between cell death and content of copper and zinc. Particles from both Pb-containing and Pb-free ammunition were able to induce oxidative stress and the proinflammatory marker interleukin (IL)-8 in both in vitro systems. These results support previous findings that indicate an association between gunshot emissions and metal fume fever. This study demonstrates the usefulness of combining chemical data with biological in vitro responses in assessing acute toxicological effects from emissions from firing both Pb and Pb-free ammunition. [ABSTRACT FROM PUBLISHER]

A pond in an industrial area in Sweden was selected to study adverse effects on salmon alevins from 2,4,6-trinitrotoluene (TNT)-contaminated water. Chemical screening revealed heavy contamination of TNT and its degradation products, 2-amino-4,6-dinitrotoluene (2-ADNT) and 4-amino-2,6-dinitrotoluene (4-ADNT), ranging from 0.05 to 230 g/kg in the sediment (dry weight) within the water system. Pond water contained 3 mg/L TNT. A dilution series of pond water mixed with tap water revealed increased death frequency in alevins down to fivefold dilution (approximate 0.4 mg TNT/L). Uptake was concentration dependent, reaching 7, 9, and 22 μg/g tissue for TNT, 2-ADNT, and 4-ADNT at the highest test concentration. A time-dependent uptake of TNT and its degradation products was found at a water concentration of 0.08 mg TNT/L. Degradation products of TNT showed a more efficient uptake compared to native TNT, and accumulation of 4-ADNT was more pronounced during the late phase of the 40-d exposure study. Bioconcentration factors (BCF) (0.34, 52, and 134 ml/g for TNT, 2-ADNT, and 4-ADNT, respectively) demonstrated a significant uptake of the metabolite 4-ADNT in alevin tissue. Disturbed physiological conditions and delayed development in alevins were not studied, but may not be excluded even at 125-fold diluted pond water (0.016 mg TNT/L). BCF data indicated that bioaccumulation of TNT metabolites need to be considered in TNT chronic toxicity. Fish species and age differences in the accumulation of TNT metabolites need to be further studied. [ABSTRACT FROM AUTHOR]

It can be problematic to collect representative samples in the occupational environment of deployed soldiers using personal samplers. In this study, several air sampling strategies were examined to identify the most efficient method for collecting air samples that were representative of the soldiers' exposure profiles at the Swedish KFOR Camp Victoria outside Pristina, Kosovo. Stationary monitoring was performed during two 5-day sampling campaigns, one in summer and one in winter. The acquired data were related to measurements obtained by personal monitoring of three and four subgroups, respectively. Patrolling soldiers, mechanics, and indoor workers were selected to represent groups with different exposure profiles, and the particles, metals associated with particles, nitrogen dioxide, sulfur dioxide, polycyclic aromatic hydrocarbons, aldehydes, and volatile organic compounds that they were exposed to were measured. Generally, low concentrations of the analytes were found in both sampling periods, but the variability was greater in the winter campaign. Samples collected by stationary samplers captured most of the variation in the personnel's exposure, according to principal component analysis (PCA). However, the results also indicate that personal exposure to most potential pollutants would be underestimated if a single outdoor station was used to monitor them. Nevertheless, combined data from stations located outdoors and in relevant microenvironments (workshop, office, and guard station) provided substantially better representation. Thus, it may be possible to obtain monitoring data without using personal samplers in these inherently problematic situations. [ABSTRACT FROM AUTHOR]

The main objective of this study was to perform an initial characterization of Swedish soldiers' exposure to air pollutants in Afghanistan and screen for potential health hazards. Stationary monitoring was performed in two military camps, International Security Assistance Force Headquarters in Kabul and Camp Northern Lights in Mazar-e Sharif, at both outdoor and indoor locations. A broad screening including particulate matter (PM10 and PM2.5), polycyclic aromatic hydrocarbons (PAHs), oxygenated PAHs, n-alkanes, nitrogen dioxide (NO2), sulfur dioxide, toxic metals, and volatile organic compounds (VOCs) was performed over 2 weeks in the autumn of 2009. The results were compared to current air quality guidelines. Particulate matter was identified as the main potential health hazard since military exposure guidelines for marginal effects were exceeded outdoors. In addition, especially in Kabul, levels of particle-bound PAHs and oxy-PAHs were high, whereas levels of toxic metals were generally low. Among gaseous pollutants, elevated NO2 levels in Kabul supported combustion as a major contributor to the poor air quality. VOC levels were generally low, but levels of some pollutants exceeded current guidelines. Because of elevated concentrations of particles with a high content of toxic organics, further monitoring and characterization of the occupational environment are warranted. [ABSTRACT FROM AUTHOR]