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Carbon monoxide (CO) emitted from roasted coffee is a potential occupational respiratory exposure hazard to workers within the coffee industry. The current study objective was to estimate CO emission factors from commercially available roasted whole bean and ground coffee measured in loose form, not packaged, and to assess the utility of CO monitoring in nonventilated storage spaces such as within coffee roasting and packaging facilities, transport vessels, and cafés. Determinants affecting CO emissions from coffee were investigated, including form (whole bean vs. ground), roast level (light, medium, medium-dark, dark), and age (time since the package was opened). CO emission factors were estimated for roasted coffee samples from a variety of manufacturers purchased from local grocery stores and online. Emission tests were performed on 36 brands of coffee, some with more than one sample per brand and with various roast levels. Decaying source equations or smoothing functions were fitted to the CO concentration measurements. Maximum observed emission factors at the peak of the predicted concentration curve were adjusted by the time required to reach the maximum CO concentration and reported as emission factors (EF buildup ). Ground coffee had a significantly increased EF buildup ( P  < 0.0001) compared with whole bean. Roast level did not significantly affect emissions for whole bean ( P  = 0.72) but did for ground ( P  < 0.001) coffee. For ground coffee, medium-dark and dark roasts had significantly higher emissions than medium and light roasts. Worst-case emission factors from commercially available whole bean and ground coffee measured in loose form, not packaged, showed that roasted coffee can rapidly emit CO. CO concentrations should be monitored in storage spaces in service and manufacturing facilities as well as transport vessels to ensure exposures do not exceed occupational exposure limits. Storage spaces may need to be ventilated to control CO concentrations to safe levels. Implications : Emission rates of carbon monoxide (CO) from roasted coffee showed that unventilated or underventilated storage spaces should be monitored and ventilated, if necessary, to control CO concentrations to safe levels.

Background: We aimed to assess the content of electronic cigarette (EC) emissions for five groups of potentially toxic compounds that are known to be present in tobacco smoke: nicotine, particles, carbonyls, volatile organic compounds (VOCs), and trace elements by flavor and puffing time., Methods: We used ECs containing a common nicotine strength (1.8%) and the most popular flavors, tobacco and menthol. An automatic multiple smoking machine was used to generate EC aerosols under controlled conditions. Using a dilution chamber, we targeted nicotine concentrations similar to that of exposure in a general indoor environment. The selected toxic compounds were extracted from EC aerosols into a solid or liquid phase and analyzed with chromatographic and spectroscopic methods., Results: We found that EC aerosols contained toxic compounds including nicotine, fine and nanoparticles, carbonyls, and some toxic VOCs such as benzene and toluene. Higher mass and number concentrations of aerosol particles were generated from tobacco-flavored ECs than from menthol-flavored ECs., Conclusion: We found that diluted machine-generated EC aerosols contain some pollutants. These findings are limited by the small number of ECs tested and the conditions of testing. More comprehensive research on EC exposure extending to more brands and flavor compounds is warranted.

Desktop three-dimensional (3D) printers are becoming commonplace in business offices, public libraries, university labs and classrooms, and even private homes; however, these settings are generally not designed for exposure control. Prior experience with a variety of office equipment devices such as laser printers that emit ultrafine particles (UFP) suggests the need to characterize 3D printer emissions to enable reliable risk assessment. The aim of this study was to examine factors that influence particulate emissions from 3D printers and characterize their physical properties to inform risk assessment. Emissions were evaluated in a 0.5-m(3) chamber and in a small room (32.7 m(3)) using real-time instrumentation to measure particle number, size distribution, mass, and surface area. Factors evaluated included filament composition and color, as well as the manufacturer-provided printer emissions control technologies while printing an object. Filament type significantly influenced emissions, with acrylonitrile butadiene styrene (ABS) emitting larger particles than polylactic acid (PLA), which may have been the result of agglomeration. Geometric mean particle sizes and total particle (TP) number and mass emissions differed significantly among colors of a given filament type. Use of a cover on the printer reduced TP emissions by a factor of 2. Lung deposition calculations indicated a threefold higher PLA particle deposition in alveoli compared to ABS. Desktop 3D printers emit high levels of UFP, which are released into indoor environments where adequate ventilation may not be present to control emissions. Emissions in nonindustrial settings need to be reduced through the use of a hierarchy of controls, beginning with device design, followed by engineering controls (ventilation) and administrative controls such as choice of filament composition and color.

Unlabelled: Direct-reading organic vapor monitors are often used to measure volatile organic compound concentrations in complex chemical gas mixtures. However, there is a paucity of data on the impact of multiple gases on monitor performance, even though it is known that monitor sensitivity may vary by chemical. This study investigated the effects of interferents on the performance of the MIRAN SapphIRe Portable Ambient Air Analyzer (SAP) and Century Portable Toxic Vapor Analyzer (TVA-1000) when sampling a specific agent of interest (cyclohexane). The TVA-1000 contained a dual detector: a photoionization detector (PID) and a flame ionization detector (FID). Three devices of each monitor were challenged with different combinations of cyclohexane and potential interferent vapors (hexane, methyl ethyl ketone, trichloroethylene, and toluene) at 21°C and 90% relative humidity (RH), an extreme environmental condition. Five replicates at four target concentrations were tested: 30, 150, 300, and 475 ppm. Multiple proportions of cyclohexane to interferent enabled the determination of the interferent effect on monitor performance. The monitor concentrations were compared to reference concentrations measured using NIOSH Method 1500. Three scenarios were investigated: no response factor, cyclohexane response factor, and weighted-mixed response factor applied. False negatives occurred more frequently for PID (21.1%), followed by FID (4.8%) and SAP (0.2%). Measurements from all monitors generally had a positive bias compared to the reference measurements. Some monitor measurements exceeded twice the reference concentrations: PID (36.8%), SAP (19.8%), and FID (6.3%). Evaluation of the 95% confidence intervals indicated that performance of all monitors varied by concentration. In addition, the performance of the PID and SAP varied by presence of an interfering compound, especially toluene and hexane for the PID and trichloroethylene for the SAP. Variability and bias associated with all these monitors preclude supplanting traditional sorbent-based tube methods for measuring volatile organic compounds (VOCs), especially for compliance monitoring., Implications: Industrial hygienists need to use care when using any of the three monitor detection types to measure the concentration of unknown chemical mixtures. Monitor performance is affected by the presence of interferents. Application of manufacturer recommended response factors may not adequately scale measurements to minimize monitor bias when compared to standard reference methods. Users should calibrate their monitors to a known reference method prior to use, if possible. Each of the monitors has its own limitations, which should be considered to ensure quality measurements are reported.

Unlabelled: The performance of two direct-reading organic vapor monitors (monitors) when calibrated at different environmental conditions was compared with charcoal tube results. Three MIRAN SapphIRe portable ambient air analyzers (SAP) and three Century portable toxic vapor analyzers (TVAs) were evaluated. Prior to sampling, the monitors were calibrated per the manufacturer's instructions using methane for the TVA flame ionization detector (FID) and isobutylene for the photoionization detector (PID), whereas the SapphIRe instruments were zeroed and the instrument's manufacturer-supplied library was used. For the first series of tests ("Part 1--Same condition"), the monitors were calibrated under the same environmental conditions as those present during sampling. They were then challenged with four cyclohexane concentrations (30, 150, 300, and 475 ppm) under two extreme environmental conditions: 5 degrees C and 30% relative humidity (RH) (same/cold) and 38 degrees C and 90% RH (same/hot). For the second series of tests ("Part 2--Different condition"), the monitors were calibrated at approximately normal indoor environmental conditions (21 degrees C and 50% RH) and sampled at extreme environmental conditions (different/cold and different/hot). The monitor readings from the two methods were compared with the actual cyclohexane concentration determined from charcoal tubes using ratios and root mean square errors. A number of monitor failures, both below detection limit values in the presence of a known challenge concentration and erroneously high measurements, occurred in each part: same condition 20.7% (149/720) and different condition 42.4% (305/ 720), with a majority of the failures (> 78%) during the hot and humid conditions. All monitors performed best at the same/cold, followed by the same/hot, in terms of closeness to the reference standard method and low within-monitor variability. The ranked choice of monitors for same/cold is PID > SAP > FID; for different/cold FID > PID > SAP; for same/hot SAP > PID > FID; and for different/hot PID > SAP (FID not included due to 100% failure rate)., Implications: Direct-reading organic vapor monitors are used for assessing the concentrations of volatile organic compounds in the air at varying environmental conditions. Typical calibration is performed at laboratory temperature and pressure. The monitors may be used in atmospheres that differ from that during calibration. An understanding of the effect of calibration environment on monitor performance may provide valuable information on the reliability and appropriateness of certain monitor types for industrial hygienists, emergency responders, and exposure assessment practitioners. Results of the study indicate monitor calibration should be performed at the same environmental conditions as sampling.

Healthcare settings present a challenging environment for assessing low-level concentrations of specific volatile organic compounds (VOCs) in the presence of high background concentrations of alcohol from the use of hand sanitizers and surface disinfectants. The purposes of this laboratory-based project were to develop and validate a sampling and analysis methodology for quantifying low-level VOC concentrations as well as high-level alcohol concentrations found together in healthcare settings. Sampling was conducted using evacuated canisters lined with fused silica. Gas chromatography/mass spectrometry analysis was performed using preconcentration (for ppb levels) and loop injection (for ppm levels). For a select list of 14 VOCs, bias, precision, and accuracy of both the preconcentration and loop injection methods were evaluated, as was analyte stability in evacuated canisters over 30 days. Using the preconcentration (ppb-level) method, all validation criteria were met for 13 of the 14 target analytes-ethanol, acetone, methylene chloride, hexane, chloroform, benzene, methyl methacrylate, toluene, ethylbenzene, m,p-xylene, o-xylene, alpha-pinene, and limonene. Using the loop injection (ppm-level) method, all validation criteria were met for each analyte. At ppm levels, alpha-pinene and limonene remained stable over 21 days, while the rest of the analytes were stable for 30 days. All analytes remained stable over 30 days at ppb levels. This sampling and analysis approach is a viable (i.e., accurate and stable) methodology that will enable development of VOC profiles for mixed exposures experienced by healthcare workers., (This journal is © The Royal Society of Chemistry 2012)