Three-dimensional (3D) printing with polycarbonate (PC) plastic occurs in manufacturing settings, homes, and schools. Emissions generated during printing with PC stock and bisphenol-A (BPA), an endocrine disrupter in PC, may induce adverse health effects. Inhalation of 3D printer emissions, and changes in endocrine function may lead to cardiovascular dysfunction. The goal of this study was to determine whether there were any changes in markers of peripheral or cardiovascular dysfunction in animals exposed to PC-emissions. Male Sprague Dawley rats were exposed to PC-emissions generated by 3D printing for 1, 4, 8, 15 or 30 d. Exposure induced a reduction in the expression of the antioxidant catalase (Cat) and endothelial nitric oxide synthase (eNos). Endothelin and hypoxia-induced factor 1 alpha transcripts increased after 30 d. Alterations in transcription were associated with elevations in immunostaining for estrogen and androgen receptors, nitrotyrosine, and vascular endothelial growth factor in cardiac arteries of PC-emission exposed animals. There was also a reduction eNOS immunostaining in cardiac arteries from rats exposed to PC-emissions. Histological analyses of heart sections revealed that exposure to PC-emissions resulted in vasoconstriction of cardiac arteries and thickening of the vascular smooth muscle wall, suggesting there was a prolonged vasoconstriction. These findings are consistent with studies showing that inhalation 3D-printer emissions affect cardiovascular function. Although BPA levels in animals were relatively low, exposure-induced changes in immunostaining for estrogen and androgen receptors in cardiac arteries suggest that changes in the action of steroid hormones may have contributed to the alterations in morphology and markers of cardiac function.

ObjectiveInhalation of diesel exhaust (DE) has been shown to be an occupational hazard in the transportation, mining, and gas and oil industries. DE also contributes to air pollution, and therefore, is a health hazard to the general public. Because of its effects on human health, changes have been made to diesel engines to reduce both the amounts of particulate matter and volatile fumes they generate. The goal of the current study was to examine the effects of inhalation of diesel exhaust.Materials and MethodsThe study presented here specifically examines the effects of exposure to 0.2 and 1.0 mg/m3 DE or filtered air (6h/d for 4 d) on measures of peripheral and cardio-vascular function, and biomarkers of heart and kidney dysfunction in male rats. A Tier 2 engine used in oil and gas fracking operations was used to generate the diesel exhaust.ResultsExposure to 0.2 mg/m3 DE resulted in an increase in blood pressure 1d following the last exposure, and increases in dobutamine-induced cardiac output and stroke volume 1 and 27d after exposure. Changes in peripheral vascular responses to norepinephrine and acetylcholine were minimal as were changes in transcript expression in the heart and kidney. Exposure to 1.0 mg/m3 DE did not result in major changes in blood pressure, measures of cardiac function, peripheral vascular function or transcript expression.Discussion and ConclusionsBased on the results of this study, we suggest that exposure to DE generated by a Tier 2 compliant diesel engine generates acute effects on biomarkers indicative of cardiovascular dysfunction. Recovery occurs quickly with most measures of vascular/cardiovascular function returning to baseline levels by 7d following exposure.

Abstract Cured-in-place pipe (CIPP) is a trenchless pipe repair technology that typically uses styrene-resin impregnated liners cured with steam, hot water, or ultraviolet light to restore underground pipes without excavation. Use of the technology can expose workers and the public to styrene. Exposure to styrene may cause asthma, cancer, and contribute to hearing loss when combined with noise. Occupational exposure to styrene during installation of CIPP is an emerging issue that can be addressed with effective engineering controls and employee education and training. The National Institute for Occupational Safety and Health has previously measured overexposures to styrene in this industry. Here, we measured short-term task exposures and area/source emissions of styrene using OSHA Method ORG-89 during installation of small diameter liners (8”) with dilution ventilation controls when enclosed spaces were occupied. We measured temperature, relative humidity, wind direction, and wind speed during installation; and observed the process while systematically recording other determinants of exposure such as cure method, liner length and diameter, and number of manholes. Area styrene measurements were highest when the refrigerated truck door holding CIPP liners was opened (347 parts per million [ppm]; 2 minutes). The highest personal styrene exposure (55 ppm) occurred while a worker was in the refrigerated truck for 18 minutes. Personal styrene exposures during cutting the cured liner ranged from 1–10 ppm (5–20 minutes). Additional ventilation in the refrigerated truck, modifications of work processes, and continued employee education and training are needed to protect the health of the CIPP workforce.

Roasted coffee emits hazardous volatile organic compounds including diacetyl and 2,3-pentanedione. Workers in non-flavored coffee roasting and packaging facilities might inhale diacetyl and 2,3-pentanedione from roasted coffee above occupational exposure limits depending on their work activities and proximity to the source of emissions. Objectives of this laboratory study were to: (1) investigate factors affecting specific emission rates (SERs) of diacetyl and 2,3-pentanedione from freshly roasted coffee, (2) explore the effect of time on SERs of coffee stored in sealed bags for 10-days, and (3) predict exposures to workers in hypothetical workplace scenarios. Two roast levels (light and dark) and three physical forms (whole bean, coarse ground, and fine ground) were investigated. Particle size for whole bean and ground coffee were analyzed using geometric mean of Feret diameter. Emitted chemicals were collected on thermal desorption tubes and quantified using mass spectrometry analysis. SERs developed here coupled with information from previous field surveys provided model input to estimate worker exposures during various activities using a probabilistic, near-field/far-field model. For freshly roasted coffee, mean SER of diacetyl and 2,3-pentantedione increased with decreasing particle size of the physical form (whole bean < coarse ground < fine ground) but was not consistent with roast levels. SERs from freshly roasted coffee increased with roast level for diacetyl but did not change for 2,3-pentanedione. Mean SERs were greatest for diacetyl at 3.60 mg kg(-1) h(-1) for dark, fine ground and for 2,3-pentanedione at 3.88 mg kg(-1) h(-1) for light, fine ground. For storage, SERs of whole bean remained constant while SERs of dark roast ground coffee decreased and light roast ground coffee increased. Modeling demonstrated that near-field exposures depend on proximity to the source, duration of exposure, and air velocities in the near-field further supporting previously reported chemical air measurements in coffee roasting and packaging facilities. Control of source emissions using local exhaust ventilation especially around grinding activities as well as modification of work practices could be used to reduce exposures in this workforce.

As of February 18, 2020, the e-cigarette, or vaping, product use associated lung injury (EVALI) outbreak caused the hospitalization of a total of 2,807 patients and claimed 68 lives in the United States. Though investigations have reported a strong association with vitamin E acetate (VEA), evidence from reported EVALI cases is not sufficient to rule out the contribution of other chemicals of concern, including chemicals in either THC or non-THC products. This study characterized chemicals evolved when diluent oils were heated to temperatures that mimic e-cigarette, or vaping, products (EVPs) to investigate production of potentially toxic chemicals that might have caused lung injury. VEA, vitamin E, coconut, and medium chain triglyceride (MCT) oil were each diluted with ethanol and then tested for constituents and impurities using a gas chromatograph mass spectrometer (GC/MS). Undiluted oils were heated at 25°C (control), 150°C, and 250°C in an inert chamber to mimic a range of temperatures indicative of aerosolization from EVPs. Volatilized chemicals were collected using thermal desorption tubes, analyzed using a GC/MS, and identified. Presence of identified chemicals was confirmed using retention time and ion spectra matching with analytic standards. Direct analysis of oils, as received, revealed that VEA and vitamin E were the main constituents of their oils, and coconut and MCT oils were nearly identical having two main constituents: glycerol tricaprylate and 2-(decanoyloxy) propane-1,3-diyl dioctanoate. More chemicals were measured and with greater intensities when diluent oils were heated at 250°C compared to 150°C and 25°C. Vitamin E and coconut/MCT oils produced different chemical emissions. The presence of some identified chemicals is of potential health consequence because many are known respiratory irritants and acute respiratory toxins. Exposure to a mixture of hazardous chemicals may be relevant to the development or exacerbation of EVALI, especially when in concert with physical damage caused by lung deposition of aerosols produced by aerosolizing diluent oils.

Vat photopolymerization (VP), a type of additive manufacturing process that cures resin to build objects, can emit potentially hazardous particles and gases. We evaluated two VP technologies, stereolithography (SLA) and digital light processing (DLP), in three separate environmental chambers to understand task-based impacts on indoor air quality. Airborne particles, total volatile organic compounds (TVOCs), and/or specific volatile organic compounds (VOCs) were monitored during each task to evaluate their exposure potential. Regardless of duration, all tasks released particles and organic gases, though concentrations varied between SLA and DLP processes and among tasks. Maximum particle concentrations reached 1200 #/cm3 and some aerosols contained potentially hazardous elements such as barium, chromium, and manganese. TVOC concentrations were highest for the isopropyl alcohol (IPA) rinsing, soaking, and drying post-processing tasks (up to 36.8 mg/m3), lowest for the resin pouring pre-printing, printing, and resin recovery post-printing tasks (up to 0.1 mg/m3), and intermediate for the curing post-processing task (up to 3 mg/m3). Individual VOCs included, among others, the potential occupational carcinogen acetaldehyde and the immune sensitizer 2-hydroxypropyl methacrylate (pouring, printing, recovery, and curing tasks). Careful consideration of all tasks is important for the development of strategies to minimize indoor air pollution and exposure potential from VP processes.

Roasted coffee and many coffee flavorings emit volatile organic compounds (VOCs) including diacetyl and 2,3-pentanedione. Exposures to VOCs during roasting, packaging, grinding, and flavoring coffee can negatively impact the respiratory health of workers. Inhalational exposures to diacetyl and 2,3-pentanedione can cause obliterative bronchiolitis. This study summarizes exposures to and emissions of VOCs in 17 coffee roasting and packaging facilities that included 10 cafés. We collected 415 personal and 760 area full-shift, and 606 personal task-based air samples for diacetyl, 2,3-pentanedione, 2,3-hexanedione, and acetoin using silica gel tubes. We also collected 296 instantaneous activity and 312 instantaneous source air measurements for 18 VOCs using evacuated canisters. The highest personal full-shift exposure in part per billion (ppb) to diacetyl [geometric mean (GM) 21 ppb; 95th percentile (P95) 79 ppb] and 2,3-pentanedione (GM 15 ppb; P95 52 ppb) were measured for production workers in flavored coffee production areas. These workers also had the highest percentage of measurements above the NIOSH Recommended Exposure Limit (REL) for diacetyl (95%) and 2,3-pentanedione (77%). Personal exposures to diacetyl (GM 0.9 ppb; P95 6.0 ppb) and 2,3-pentanedione (GM 0.7 ppb; P95 4.4 ppb) were the lowest for non-production workers of facilities that did not flavor coffee. Job groups with the highest personal full-shift exposures to diacetyl and 2,3-pentanedione were flavoring workers (GM 34 and 38 ppb), packaging workers (GM 27 and 19 ppb) and grinder operator (GM 26 and 22 ppb), respectively, in flavored coffee facilities, and packaging workers (GM 8.0 and 4.4 ppb) and production workers (GM 6.3 and 4.6 ppb) in non-flavored coffee facilities. Baristas in cafés had mean full-shift exposures below the RELs (GM 4.1 ppb diacetyl; GM 4.6 ppb 2,3-pentanedione). The tasks, activities, and sources associated with flavoring in flavored coffee facilities and grinding in non-flavored coffee facilities, had some of the highest GM and P95 estimates for both diacetyl and 2,3-pentanedione. Controlling emissions at grinding machines and flavoring areas and isolating higher exposure areas (e.g., flavoring, grinding, and packaging areas) from the main production space and from administrative or non-production spaces is essential for maintaining exposure control.

Background Fused filament fabrication 3-D printing with acrylonitrile butadiene styrene (ABS) filament emits ultrafine particulates (UFPs) and volatile organic compounds (VOCs). However, the toxicological implications of the emissions generated during 3-D printing have not been fully elucidated. Aim and methods The goal of this study was to investigate thein vivotoxicity of ABS-emissions from a commercial desktop 3-D printer. Male Sprague Dawley rats were exposed to a single concentration of ABS-emissions or air for 4 hours/day, 4 days/week for five exposure durations (1, 4, 8, 15, and 30 days). At 24 hours after the last exposure, rats were assessed for pulmonary injury, inflammation, and oxidative stress as well as systemic toxicity. Results and discussion 3-D printing generated particulate with average particle mass concentration of 240 +/- 90 mu g/m(3), with an average geometric mean particle mobility diameter of 85 nm (geometric standard deviation = 1.6). The number of macrophages increased significantly at day 15. In bronchoalveolar lavage, IFN-gamma and IL-10 were significantly higher at days 1 and 4, with IL-10 levels reaching a peak at day 15 in ABS-exposed rats. Neither pulmonary oxidative stress responses nor histopathological changes of the lungs and nasal passages were found among the treatments. There was an increase in platelets and monocytes in the circulation at day 15. Several serum biomarkers of hepatic and kidney functions were significantly higher at day 1. Conclusions At the current experimental conditions applied, it was concluded that the emissions from ABS filament caused minimal transient pulmonary and systemic toxicity.

Abstract Objective: Fused filament fabrication “3-dimensional (3-D)” printing has expanded beyond the workplace to 3-D printers and pens for use by children as toys to create objects. Materials and methods: Emissions from two brands of toy 3-D pens and one brand of toy 3-D printer were characterized in a 0.6 m3 chamber (particle number, size, elemental composition; concentrations of individual and total volatile organic compounds (TVOC)). The effects of print parameters on these emission metrics were evaluated using mixed-effects models. Emissions data were used to model particle lung deposition and TVOC exposure potential. Results: Geometric mean particle yields (106–1010 particles/g printed) and sizes (30–300 nm) and TVOC yields (<detectable to 590 µg TVOC/g printed) for the toys were similar to those from 3-D printers used in workplaces. Metal emissions included manganese (1.6–92.3 ng/g printed) and lead (0.13–1.2 ng/g printed). Among toys, extruder nozzle conditions (diameter, temperature) and filament (type, color, and extrusion speed) significantly influenced particle and TVOC emissions. Dose modeling indicated that emitted particles would deposit in the lung alveoli of children. Exposure modeling indicated that TVOC concentration from use of a single toy would be 1–31 µg/m3 in a classroom and 3–154 µg/m3 in a residential living room. Discussion: Potential exists for inhalation of organic vapors and metal-containing particles during use of these toys. Conclusions: If deemed appropriate, e.g. where multiple toys are used in a poorly ventilated area or a toy is positioned near a child’s breathing zone, control technologies should be implemented to reduce emissions and exposure risk.

Evacuated canisters offer an opportunity to expand on the way volatile organic compounds (VOCs) are measured in indoor air quality investigations, industrial hygiene assessments, and emergency response scenarios. There is a growing need for alternative sampling methods for VOCs as traditional sorbent tube sampling methods may not adequately capture the multitude of chemicals present in mixed exposure environments due to sorbent-analyte specificity.;This study is part of a larger work designed to address this need across a suite of 17 VOCs. This study assesses generation and evaluation methods for the production of reference evacuated canister samples as part of an ASTM-style interlaboratory study. The interlaboratory study was designed to assess evacuated canister method performance for the development of a National Institute for Occupational Safety and Health (NIOSH) Manual of Analytical Methods protocol.;The reference canister samples were generated in two concentration ranges (part-per-million and part-per-billion) and at three nominal concentration levels within the two ranges. For the PPB range, samples were generated using either a flow-based dilution or combination pressure dilution and canister-to-canister transfer technique. For the PPM range, samples were generated by either the combination pressure dilution and canister-to-canister transfer technique, or a manifold dilution method. The reference canister samples were analyzed via gas chromatography-mass spectrometry (GC-MS). The performance of three preparation methods and three analytical methods were assessed by the NIOSH 95% confidence interval on accuracy criterion.;Results indicate that method accuracy is concentration dependent with respect to certain combinations of analytical method, preparation technique, and analyte. Some sample preparation techniques were found to be better for certain groups of compounds and at certain concentration ranges. All 17 VOCs passed the NIOSH accuracy criterion for the PPM range when prepared using the pressure dilution technique and analyzed via a 1 cc loop injection into a GC-MS. For the PPB range of concentration levels, 15 VOCs passed the NIOSH accuracy criterion when prepared by the pressure dilution method and analyzed via a 250 cc, cryogenically concentrated injection into a GC-MS.

ABSTRACT This experimental study aimed to evaluate airborne particulates and volatile organic compounds (VOCs) from surgical smoke when a local exhaust ventilation (LEV) system is in place. Surgical smoke was generated from human tissue in an unoccupied operating room using an electrocautery surgical device for 15 min with 3 different test settings: (1) without LEV control; (2) control with a wall irrigation suction unit with an in-line ultra-low penetration air filter; and (3) control with a smoke evacuation system. Flow rate of LEVs was approximately 35 L/min and suction was maintained within 5 cm of electrocautery interaction site. A total of 6 experiments were conducted. Particle number and mass concentrations were measured using direct reading instruments including a condensation particle counter (CPC), a light-scattering laser photometer (DustTrak DRX), a scanning mobility particle sizer (SMPS), an aerodynamic particle sizer (APS), and a viable particle counter. Selected VOCs were collected using evacuated canisters using grab, personal and area sampling techniques. The largest average particle and VOCs concentrations were found in the absence of LEV control followed by LEV controls. Average ratios of LEV controls to without LEV control ranged 0.24–0.33 (CPC), 0.28–0.39 (SMPS), 0.14–0.31 (DustTrak DRX), and 0.26–0.55 (APS). Ethanol and isopropyl alcohol were dominant in the canister samples. Acetaldehyde, acetone, acetonitrile, benzene, hexane, styrene, and toluene were detected but at lower concentrations (<500 μg/m3) and concentrations of the VOCs were much less than the National Institute for Occupational Safety and Health recommended exposure limit values. Utilization of the LEVs for surgical smoke control can significantly reduce but not completely eliminate airborne particles and VOCs.

The use of electronic nicotine delivery systems continues to gain popularity, and there is concern for potential health risks from inhalation of aerosol and vapor produced by these devices. An analytical method was developed that provided quantitative and qualitative chemical information for characterizing the volatile constituents of bulk electronic cigarette liquids (e-liquids) using a static headspace technique. Volatile organic compounds (VOCs) were screened from a convenience sample of 146 e-liquids by equilibrating 1 g of each e-liquid in amber vials for 24 h at room temperature. Headspace was transferred to an evacuated canister and quantitatively analyzed for 20 VOCs as well as tentatively identified compounds using a preconcentrator/gas chromatography/mass spectrometer system. The e-liquids were classified into flavor categories including brown, fruit, hybrid dairy, menthol, mint, none, tobacco, and other. 2,3-Butanedione was found at the highest concentration in brown flavor types, but was also found in fruit, hybrid dairy, and menthol flavor types. Benzene was observed at concentrations that are concerning given the carcinogenicity of this compound (max 1.6 ppm in a fruit flavor type). The proposed headspace analysis technique coupled with partition coefficients allows for a rapid and sensitive prediction of the volatile content in the liquid. The technique does not require onerous sample preparation, dilution with organic solvents, or sampling at elevated temperatures. Static headspace screening of e-liquids allows for the identification of volatile chemical constituents which is critical for identifying and controlling emission of potentially hazardous constituents in the workplace.

Resistance spot welding is a common process to join metals in the automotive industry. Adhesives are often used as sealers to seams of metals that are joined. Anti-spatter compounds sometimes are sprayed onto metals to be welded to improve the weldability. Spot welding produces complex aerosols composed of metal and volatile compounds (VOCs) which can cause lung disease in workers. Male Sprague-Dawley rats (n = 12/treatment group) were exposed by inhalation to 25 mg/m3 of aerosol for 4 h/day x 8 days during spot welding of galvanized zinc (Zn)-coated steel in the presence or absence of a glue or anti-spatter spray. Controls were exposed to filtered air. Particle size distribution and chemical composition of the generated aerosol were determined. At 1 and 7 days after exposure, bronchoalveolar lavage (BAL) was performed to assess lung toxicity. The generated particles mostly were in the submicron size range with a significant number of nanometer-sized particles formed. The primary metals present in the fumes were Fe (72.5%) and Zn (26.3%). The addition of the anti-spatter spray and glue did affect particle size distribution when spot welding galvanized steel, whereas they had no effect on metal composition. Multiple VOCs (e.g., methyl methacrylate, acetaldehyde, ethanol, acetone, benzene, xylene) were identified when spot welding using either the glue or the anti-spatter spray that were not present when welding alone. Markers of lung injury (BAL lactate dehydrogenase) and inflammation (total BAL cells/neutrophils and cytokines/chemokines) were significantly elevated compared to controls 1 day after exposure to the spot welding fumes. The elevated pulmonary response was transient as lung toxicity mostly returned to control values by 7 days. The VOCs or the concentrations that they were generated during the animal exposures had no measurable effect on the pulmonary responses. Inhalation of galvanized spot welding fumes caused acute lung toxicity most likely due to the short-term exposure of particles that contain Zn. Published by Elsevier Ireland Ltd.

The chemical compound 1-Chloro-4-(trifluoromethyl) benzene (CAS No: 98-56-6)—also known as PCBTF, Oxsol 100, or Parachlorobenzotrifluoride—was nominated to the National Toxicology Program (NTP) for toxicity and carcinogenicity studies (http://ntp.niehs.nih.gov/ntp/noms/support_docs/pcbtf06-0409.pdf). The nomination was based on the increasing use of PCBTF by industries and consumers, since it was exempted by the Environmental Protection Agency (EPA) as a volatile organic compound in emissions reporting on the basis of not reacting in a manner that would contribute to the formation of tropospheric ozone.(1) Although PCBTF is no longer manufactured in the United States, approximately 29 million lbs. were imported in 2012(2) and used in various applications to replace other chlorinated solvents with known environmental or human health hazards. Those applications include the automotive industry as industry-wide applications in coatings, thinners, and cleaning solvents, and repair and maintenance cleaning and as a consumer product for cosmetic stain removal and aerosol rust prevention.(3) The toxicity information on PCBTF is available from various resources(4,5) including the NTP website.(6) These studies, however, are limited to short-term toxicity, and chronic inhalation toxicity and carcinogenicity studies are unavailable. There are no Occupational Safety and Health Administration (OSHA) regulations specific to limiting occupational exposures to PCBTF. The National Institute for Occupational Safety and Health (NIOSH) has not established a time-weighted average (TWA) recommended exposure level, and the American Conference of Governmental Industrial Hygienists (ACGIH®) has not established a TWA-threshold limit value (TLV®) for PCBTF. The Occidental Chemical Corporation, which used to manufacture PCBTF in the United States, established a corporate exposure limit (CEL), which was a TWA limit of 25 ppm (185 mg/m3) for an 8-hr work-shift. The toxicological basis for setting this limit is not known to us. However, Occidental Chemical Corporation no longer manufactures or imports PCBTF into the United States. The purpose of this case study is to determine industry-wide occupational inhalation exposures using available industrial hygiene sampling methods. This information can be used to benchmark exposure concentrations that may be applied in future studies of inhalation toxicity in animal models. In addition, side-by-side samples of a pumped (active) and diffusive (passive) sorbent tubes were taken to compare concentration ratios between the active and passive sampling methods. Workplace Description Vehicle manufacturing plants Four vehicle manufacturing plants—helicopter (Plant A), aircraft (Plants B and C), and automobile (Plant C)—were recruited through personal contacts. All manufacturing plants were identified by code for confidentiality. At Plant A, PCBTF was used as a cleaning solvent to remove residual glue after upholstery removal during interior refurbishment. The cleaning work was done manually under a slotted back-draft ventilation hood. PCBTF was used during primer application prior to coating of an airplane at Plants B and C and plastic adhesive promoter application at Plant D. All painters wore airline respirators and applied the PCBTF-containing substances using spray guns under downdraft ventilation. The mixing worker at Plant C combined base (23 L with 0% PCBTF), activator (23 L with 30–60% PCBTF), and thinner (6 L with 60–90% PCBTF) to make primer. The mixing task was done under a canopy hood and the mixer wore a full facepiece air-purifying respirator. The amount of PCBTF per worker used during the specific tasks varied ranging from 0.3 to 18.5 L. Table I shows a summary of workplace description including tasks, PCBTF usage, room ventilation, local exhaust ventilation, respirator type, and the amount of PCBTF used during each task. Detailed information about job tasks and personal protective equipment was described in a supplementary file. TABLE I Summary of Workplace Description (Vehicle Manufacturing Plants) Paint manufacturing plants Three paint manufacturing plants were recruited via contacting American Coatings Association. Four tasks—pre-batch making, batch making, filling, and miscellaneous—were observed. In the pre-batch making area (Plants E and G), workers transferred PCBTF-containing materials to other containers using either a pumping system or a mechanized pouring system. Containers were partially opened to place a pumping system. No respirator was required for this task at both plants. In the batch-making area (Plants E, F, and G), each batch-maker added various chemicals in a batch container, mixed the chemicals, transferred the chemicals to other containers, and cleaned the emptied batches. The batch-making task was done in a closed system for all plants except for cleaning or partially opened to add or transfer materials. The batch-makers wore no respirators during mixing but wore dust masks (Plants E and G) and half facepiece respirators (Plant F) when manually adding materials. The filling operators (Plants E, F, and G) filled containers with final product from an automated dispenser and placed lids. No respirator was required for the filling task. Other miscellaneous tasks included lab quality control testing, cleaning, batch adjusting, color mixing, and pilot working. The workplaces for all tasks were controlled by general ventilation in addition to any local exhaust ventilation systems. Table II shows a summary of workplace description and detailed information for each task was described in a supplementary file. TABLE II Summary of Workplace Description (Paint Manufacturing Plants) METHODS Sample Monitoring At the four vehicle manufacturing plants, 28 personal and 8 area sample pairs were collected using actively pumped coconut-shell charcoal tubes (SKC 226-01, SKC Inc., Eighty Four, PA) and diffusive charcoal badges (SKC 575-001, SKC Inc.). The former represents an active sampling method (i.e., drawing air throughout the media using a pump) and the latter represents a passive sampling method (i.e., air intake by chemical diffusion). All workers sampled at the vehicle manufacturing plants handled the PCBTF-containing materials. At the three paint manufacturing plants, 64 personal and 26 area sample pairs were collected. Participants were workers who handled PCBTF and workers who did not but were in close proximity to the workers handling PCBTF. The sample size and sampling time for each task are listed in Table III. The sampling times ranged from 15 to 407 min for the vehicle manufacturing plants and 70 to 535 min for the paint manufacturing plants. Two types of sampling pumps, Pocket Pump (SKC Inc.) and Gilian LFS-113 (Sensidyne, Clearwater, FL), were used at sampling flow rates between 20 and 200 ml/min for the active sampling method. The sampling flow rates were adjusted based on anticipated concentrations, previously collected from similar workplaces. Each pump was calibrated before and after sample collection with a DryCal DC-Lite device (BIOS International Corporation, Butler, NJ) to assure the difference between pre- and post-sampling flow rates was within ±5%. The position of passive and active samplers for the personal sampling method was randomized to minimize bias from workers’ handiness (i.e., not always on the left or right of worker’s collar). All field surveys were performed between 2010 and 2012. TABLE III Air Sampling Results Using Active Sampling Method All active and passive samples were analyzed with gas chromatography/flame ionization detector according to the NIOSH Manual of Analytical Methods (NMAM) 1026(7) by the NIOSH contract laboratory. The NIOSH method has suggested a maximum of 25 ppm for a 10 L air sample with a working range between 0.024 and 9.15 ppm (0.178 to 67.8 mg/m3). Yost and Harper(8) tested passive badges at various loadings in a standard atmosphere chamber in which the test concentrations of the standard atmosphere were confirmed by means of coconut charcoal tubes for time period up to 8 hr. Those loadings were 0.012 mg (0.01×CEL), 0.123 mg (0.1×CEL), 0.505 mg (0.5×CEL), 1.10 mg (1.0×CEL), and 2.09 mg (2.0×CEL). Yost and Harper(8) showed charcoal tubes and passive badges to have a large capacity covering up to 2 times the CEL and the maximum concentration suggested by the NIOSH method. The mass concentrations of passive badges were calculated using the average sampling rate of 11.8 ml/min.(8) From each sampling site, 1–10 field blank samples were collected. In this study, sample results were not adjusted by field blank samples because almost all field blank samples (96% of 56 field blank samples) showed non-detectable masses. The limit of detection was 0.1 – 0.7 μg for both diffusive badge and charcoal tube. The limit of quantitation ranged between 0.5 – 2.5 μg for the diffusive charcoal badge and 0.5 – 3.4 μg for the charcoal tube. Three sample pairs showing at least one of each pair resulted in less than the limit of detection were excluded. None of the samples except for the three sample pairs showed less than the limit of quantitation.

A polyvinyl chloride (PVC) cassette insert with PVC filter (ACCU-CAP) in a 37-mm closed-face cassette (CFC) was designed for gravimetric analysis. A customized version of the ACCU-CAP, also to be used in the CFC, was manufactured from an acid-digestible cellulose-acetate cassette insert joined to a mixed cellulose ester (MCE) filter for wet chemical analysis. The aim of this study was to compare metal particle concentrations as sampled by the customized insert (CI) in a CFC sampler with the traditional sampling method using only a MCE filter in the CFC. Thirty-nine personal and 13 area samples were taken using paired filter-based CFC and the CI in CFC samplers at a solder manufacturing plant. The CI was removed from its CFC, and digested and analyzed as a whole. The MCE filter from the typical CFC was removed for analysis and then the interior of the cassette was wiped with Ghost Wipe for a separate analysis. The MCE filter only, Ghost Wipe, and CI were separately dissolved in heated nitric acid for ICP-MS analysis. Overall, the geometric mean concentration of the filter-only (FO) samples was considerably lower than that of the CI samples, by 53% for lead and 32% for tin. However, if the FO analysis was added to the corresponding Ghost Wipe analysis, i.e., filter+interior wipe (FW), the geometric mean concentrations of the FW results were similar to those of the CI results (by 113% for lead and 98% for tin). For both lead and tin the comparison of (log-transformed) metal concentrations between the FW and CI results showed no statistically significant difference (p-value = 0.3009 for lead and 0.800 for tin), while the comparison between the FO and CI results shows statistically significant differences (all p-values < 0.05). In conclusion, incorporating the sampler internal non-filter deposits by wiping or use of an internal filter capsule gave higher results than analyzing only the filter. Close agreement between the two methods of including non-filter deposits is an indication of general equivalency.