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Background: The industrial use of novel-manufactured nanomaterials such as carbon nanotubes and carbon nanodiscs is increasing globally. Occupational exposure can occur during production, downstream use, and disposal. The health effects of many nanomaterials are not yet fully characterized and to handle nano-objects, their aggregates and agglomerates >100nm (NOAA), a high degree of control measures and personal protective equipment are required. The emission of airborne NOAA during production and handling can contaminate workplace surfaces with dust, which can be resuspended resulting in secondary inhalation exposures and dermal exposures. This study surveys the presence of carbon-based nanomaterials, such as multi-walled carbon nanotubes (MWCNTs) and carbon nanodiscs, as surface contamination at a small-scale producer using a novel tape sampling method. Methods: Eighteen different surfaces at a small-scale producer were sampled with an adhesive tape sampling method. The surfaces selected were associated with the production and handling of MWCNT powder in the near-field zone. Surfaces in the far-field zone were also sampled. In addition, tape stripping of the skin was performed on one worker. The tape samples were analysed with scanning electron microscopy to detect the carbon-based NOAA. Air sampling with a personal impactor was also performed on a worker who was producing MWCNTs the same day as the tape samples were collected. Results: MWCNTs were detected in 50% of the collected tape samples and carbon nanodiscs in 17%. MWCNTs and carbon nanodiscs were identified in all parts of the workplace, thus, increasing the risk for secondary inhalation and dermal exposure of the workers. Both airborne MWCNTs and carbon nanodiscs were detected in the personal impactor samples. The tape-strip samples from the worker showed no presence of carbon-containing nanoparticles. Conclusions: Tape sampling is a functional method for detecting surface contamination of carbon-based NOAA and for exposure control during production at potentially any workplace that produces or handles such manufactured nanomaterials. With the tape method, it is possible to monitor if a potential for secondary inhalation exposure or dermal exposure exists through resuspension of dust deposited on workplace surfaces. By means of air sampling, we could confirm that carbon nanodiscs were resuspended into the air at the workplace even though they were not handled during that particular work shift. MWCNTs were detected in the air samples, but can have been derived from either resuspension or from the work tasks with MWCNTs that were performed during the air sampling. Tape sampling is a complementary method to air sampling and together these two methods provide a better view of the hygienic situation in workplaces where NOAA can be emitted into work environments. [ABSTRACT FROM AUTHOR]

Introduction: Workers involved in the production of Cd/As-based photovoltaic modules may be routinely or accidentally exposed to As- or Cd-containing inorganic compounds. Methods: Workers' exposure to As and Cd was investigated by environmental monitoring following a worst-case approach and biological monitoring from the preparation of the working facility to its decommissioning. Workplace surface contamination was also evaluated through wipe-test sampling. Results: The highest mean airborne concentrations were found during maintenance activities (As = 0.0068 μg m−3; Cd = 7.66 μg m−3) and laboratory simulations (As = 0.0075 μg m−3; Cd = 11.2 μg m−3). These types of operations were conducted for a limited time during a typical work shift and only in specifically suited containment areas, where the highest surface concentrations were also found (laboratory: As = 2.94 μg m−2, Cd = 167 μg m−2; powder containment booth: As = 4.35 μg m−2, Cd = 1500 μg m−2). The As and Cd urinary levels (As_u; Cd_u) were not significantly different for exposed (As_u = 6.11 ± 1.74 μg 1−1; Cd_u = 0.24 ± 2.36 μg g−1 creatinine) and unexposed workers (As_u = 6.11 ± 1.75 μg 1−1; Cd_u = 0.22 ± 2.08 μg g−1 creatinine). Conclusion: Despite airborne arsenic and cadmium exposure well below the threshold limit value (TLV) when the operation is appropriately maintained in line, workers who are involved in various operations (maintenance, laboratory test) could potentially be at risk of significant exposure, well in excess of the TLV. Nevertheless, the biological monitoring data did not show significant occupationally related arsenic and cadmium intake in workers and no significant changes or differences in arsenic and cadmium urinary level among the exposed and unexposed workers were found. [ABSTRACT FROM AUTHOR]

Introduction: We investigated nanomaterial release associated with the contamination of protective clothing during manipulation of clothing fabrics contaminated with nanoparticles. Nanomaterials, when released as airborne nanoparticles, can cause inhalation exposure which is the route of exposure of most concern to cause adverse health effects. Measurement of such nanparticle re-suspension has not yet been conducted. Protective clothing can be contaminated with airborne nanoparticles during handling and operating processes, typically on the arms and front of the body. The contaminated clothing could release nanoparticles in the general room while performing other activities and manipulating the clothing after work. Methods: The exposures associated with three different fabric materials of contaminated laboratory coats (cotton, polyester, and Tyvek), including the magnitude of contamination and particle release, were investigated in this study by measuring the number concentration increase and the weight change on fabric pieces. This study simulated real life occupational exposure scenarios and was performed in both regular and clean room environments to investigate the effect of background aerosols on the measurements. Concentration were measured using particle spectrometers for diameters from 10nm to 10 µm. Collected aerosol particles and contaminated fabric surfaces were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and elemental composition analysis. Results: The magnitude of particle release from contaminated lab coat fabric was found to vary by the type of fabric material; cotton fabric showed the highest level of contamination and particle release, followed by Tyvek and polyester fabrics. The polyester lab coat material was found to have the lowest particle release to deposition (R/D) ratio. The particle release number concentrations were in a range of 768-119 particles cm-3 and 586-187 particles cm-3 in regular and clean rooms, respectively. Multiple peaks were observed in the number concentration distribution data, with particle diameters peaking at 40-50 and 100-300nm. Conclusions: The SEM analysis of the contaminated fabric surface found test particles and other environmental particles. The elemental composition analysis presented detectable response to the studied alumina oxide particles. The laboratory coat primarily made of cotton woven material is not recommended for worker protection against nanoparticle exposure because of the highest particle contamination and release ability. In addition, the result demonstrated that a well-controlled (clean- room) environment is critical to investigate the factors affecting nanoparticle interaction with protective clothing. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the association between occupational contamination and exposure levels to antineoplastic drugs and the application of control measures in a hospital work environment. Methods : Wipe samples of equipments were collected at a hospital in Osaka Prefecture, Japan, from 2007 to 2011. These samples were subjected to measurements of cyclophosphamide (CP), gemcitabine (GEM), platinum-containing drugs (Pt), and fluorouracil (5FU). Additionally, 24-h urine samples were collected from pharmacists who handled antineoplastic drugs, which were analyzed for CP and alpha-fluoro-beta-alanine (AFBA). The application of control measures was scored according to a checklist, which consisted of the following five items: safety equipment and maintenance, training and documentation, devices for safe handling, personal protective equipment, and emergency care. The aim was to obtain a score of 80%. Results : The median CP, GEM, and 5FU concentrations of all wipe samples were significantly lower during the period when the mean score was >80% (attainment period) versus when the mean score was ≤80% (nonattainment period; all P < 0.001, Mann–Whitney’s U-test). Additionally, the median urinary CP and AFBA concentrations of pharmacists during the attainment period tended to be lower than that of those during the nonattainment period (P = 0.061 and 0.061, respectively, using Mann–Whitney’s U-test). Conclusions : Contamination and levels of exposure to antineoplastic drugs decreased with a score higher than 80%. The scores of the items on the checklist appeared to adequately reflect the condition of the control measures, as increases in all five items were associated with reductions in the contamination by and levels of exposure to all drugs. [ABSTRACT FROM PUBLISHER]

This paper integrates perspectives from analytical chemistry, environmental engineering, and industrial hygiene to better understand how workers may be exposed to perfluorinated carboxylic acids when handling them in the workplace in order to identify appropriate exposure controls. Due to the dramatic difference in physical properties of the protonated acid form and the anionic form, this family of chemicals provides unique industrial hygiene challenges. Workplace monitoring, experimental data, and modeling results were used to ascertain the most probable workplace exposure sources and transport mechanisms for perfluorooctanoic acid (PFOA) and its ammonium salt (APFO). PFOA is biopersistent and its measurement in the blood has been used to assess human exposure since it integrates exposure from all routes of entry. Monitoring suggests that inhalation of airborne material may be an important exposure route. Transport studies indicated that, under low pH conditions, PFOA, the undissociated (acid) species, actively partitions from water into air. In addition, solid-phase PFOA and APFO may also sublime into the air. Modeling studies determined that contributions from surface sublimation and loss from low pH aqueous solutions can be significant potential sources of workplace exposure. These findings suggest that keeping surfaces clean, preventing accumulation of material in unventilated areas, removing solids from waste trenches and sumps, and maintaining neutral pH in sumps can lower workplace exposures. [ABSTRACT FROM AUTHOR]

Objectives: Although respiratory exposures have been the primary concern with isocyanates, skin exposure also can occur and may contribute to sensitization and asthma. Methodologies to assess isocyanate skin exposure in the workplace are limited and skin exposure data scarce. The goals of this study were (i) to evaluate and validate the isocyanate colorimetric indicators against a quantitative assay, (ii) to evaluate the extent of isocyanate surface contamination and skin exposure among auto body shop workers and (iii) to evaluate isocyanate skin exposure determinants. [ABSTRACT FROM PUBLISHER]

Occupational exposure to cytotoxic drugs of hospital personnel involved in their preparation and administration is a major issue: ever since the introduction of protective measures in recent decades, the handling of these drugs has always been referred to as an occupational health hazard. Isolator technology was one of the protective equipments aimed at providing safe handling, but it has not yet been studied regarding contamination. The present study evaluates surface contamination with four cytotoxic drugs [cyclophosphamide (CP), ifosfamide (IF), 5 fluorouracil (5FU) and methotrexate (MTX)] by wipe sampling in two hospital pharmacies. Wipe samples were taken from work surfaces both located inside and outside the isolators. In addition, working gloves, the surface of infusion bags filled with 5FU or CP, and gloves used in simulation of drug administration were analyzed. Contamination was routinely found inside the isolators but rarely outside the isolators, indicating that the isolator technology is offering good protection of the cytotoxic drug handlers as well as the environment during preparation. On the other hand, contamination was found on the surfaces of infusion bags and gloves in contact with infusion bags filled with cytotoxic drugs. Consequently, personal protective equipment is still recommended during the manipulation and administration of the drugs because of potentially contaminated drug vials and final products. [ABSTRACT FROM AUTHOR]

Workplaces, e.g. hospital pharmacies and hospital departments, where antineoplastic drugs are handled might be contaminated with these drugs, and pharmacy personnel and health care workers may be exposed. In this study potential sources for exposure of antineoplastic drugs were investigated. Unbroken drug vials and tablet blister packages, both containing cyclophosphamide (CP) and their outer packaging were wipe sampled. Analysis was performed by liquid chromatography combined with tandem mass spectrometry (LC-MS/MS). The result showed that almost every part of the primary packaging was contaminated with CP and ifosfamide (IF). However, the amounts of CP and IF were low, and most likely not harmful for the personnel handling these packaging in association with drug preparation. The contamination must originate from the pharmaceutical manufacturer. Different surfaces in the preparation unit of a Swedish hospital pharmacy were also investigated at two different occasions by wipe sampling. In the preparation unit CP and IF were found as contaminants on the majority of the investigated surfaces. After the first measurement the hospital pharmacy improved its routines. Lower amounts of CP and IF were detected at the second measurement. A low degree of contamination with CP and IF was also detected on the floor outside the preparation unit and this indicated a small distribution of antineoplastic drugs to the surroundings. [ABSTRACT FROM AUTHOR]

This paper reports an assessment of various methods for sampling participate surface contamination for use in the field. The results from the study will be used to develop guidance for monitoring participate surface contamination in the workplace. Three types of adhesive tape, two manual and two ‘semi-automatic’ wipe methods, and one Smair method were assessed. A field assessment of selected methods was carried out in two stages. In stage one, the manual wipes, semi-automatic wipes and adhesive tape (Scotch Tape®) were compared. In stage two, the adhesive tape (Scotch Tape®), black forensic tape, clear forensic tape and Smair were compared. Visits were made to ten metal processing facilities and participate contamination was sampled from six locations at each site. Sampling locations were chosen for their potential as points of worker dermal contact and also to represent a range of surface characteristics. The metal content of the samples were analysed using Atomic Absorption Spectrophotometry (AAS) and X-ray Fluorescence Spectro-metry (XRF). It was found that the Smair method proved to be inefficient in removing surface contamination, particularly where the surface was damp or greasy. Tape methods were found to be the most satisfactory and have considerably greater efficiency than wipe sampling. The black forensic tape is the preferred sampling medium as it is highly efficient, reproducible and easy to use. Crown Copyright © 1998 Published by Elsevier Science Ltd on behalf of British Occupational Hygiene Society. [ABSTRACT FROM AUTHOR]

The article presents a research study which examines airborne asbestos concentrations based on surface contamination measurements. Findings reveal the mean concentrations and mean resuspension factor of airborne asbestos in buildings using direct and indirect transfer methods. The description, methods, and conclusion of the study are provided.

Assessment of a field-portable energy dispersive X-ray fluorescence spectrometer (PXRFS) was carried out to determine its performance characteristics for direct analysis of surface deposits and airborne inorganic contamination collected on millipore filters. Lower limits of detection (LLDs) determined for 18 elements were found to be below the required sensitivity of analysis, one-tenth of the occupational exposure limit, with the exception of Pb and Cd. Precision of determinations above the LLD indicated that the standard deviation in analysis was less than 10% Results of PXRFS analyses of millipore filters used in sampling airborne contamination agree well with results obtained by a laboratory-based XRF method. Results of monitoring Pb, Cd, As, Hg, Fe, Mn and Ni contamination on workplace surfaces show good correlation between direct monitoring and surface wipe sampling. Levels of contaminants on workplace surfaces were found to vary between 0 and 1200 µg cm−2 on non-textile surfaces; in office areas up to 1458 µg Cd cm−2, 862 µg Pb cm−2 and 46 µg Hg cm−2 were found on carpets. The findings indicate that the portable XRF monitor can provide rapid on-site analyses of surfaces, filters and powders and thus play a key role in a cost-effective sampling and analysis strategy. Copyright © 1996 British Occupational Hygiene Society. [ABSTRACT FROM AUTHOR]

The present paper proposes a source–receptor model to schematically describe inhalation exposure to help understand the complex processes leading to inhalation of hazardous substances. The model considers a stepwise transfer of a contaminant from the source to the receptor. The conceptual model is constructed using three components, i.e. (i) the source, (ii) various transmission compartments and (iii) the receptor, and describes the contaminants emission and its pattern of transport. Based on this conceptual model, a list of nine mutually independent principal modifying factors (MFs) is proposed: activity emission potential, substance emission potential, localized control, separation, segregation, dilution, worker behavior, surface contamination and respiratory protection. These MFs describe the exposure process at a high level of abstraction so that the model can be generically applicable. A list of exposure determinants underlying each of these principal MFs is proposed to describe the exposure process at a more detailed level. The presented conceptual model is developed in conjunction with an activity taxonomy as described in a separate paper. The proposed conceptual model and MFs should be seen as ‘building blocks’ for development of higher tier exposure models. [ABSTRACT FROM AUTHOR]

Objectives: Although respiratory exposures have been the primary concern with isocyanates, skin exposure also can occur and may contribute to sensitization and asthma. Methodologies to assess isocyanate skin exposure in the workplace are limited and skin exposure data scarce. The goals of this study were (i) to evaluate and validate the isocyanate colorimetric indicators against a quantitative assay, (ii) to evaluate the extent of isocyanate surface contamination and skin exposure among auto body shop workers and (iii) to evaluate isocyanate skin exposure determinants. Methods: The colorimetric indicators were compared with a high-performance liquid chromatography (HPLC) quantitative assay based on the National Institute for Occupational Safety and Health Method 5525 using paired laboratory sampling. The colorimetric indicators were then used to assess surface contamination and skin exposure to aliphatic isocyanates in 35 auto body shops and 124 workers as part of an epidemiologic study. The positive sample rate was calculated for various surfaces, body parts and tasks. The color intensity of the colorimetric indicators was rated on a scale 0 (yellow color) to 5 (deep red). Side-by-side comparisons of the qualitative method with the quantitative HPLC assay were also performed in the field using paired samples. Results: Laboratory and field evaluation validated use of the colorimetric indicators. The rate of positive surface samples for isocyanates was 46% (n = 145/313). Thirty-four percent (73/216) of samples were positive for unprotected skin and 20% (n = 22/111) for skin under latex gloves. The highest positive rate observed on skin samples was obtained after paint mixing and spraying tasks. The colorimetric indicators were highly specific for isocyanates, but false negatives occurred when compared with the more sensitive HPLC quantitative assay. The presence of surface contamination and the performance of paint-related tasks were the major determinants of isocyanate skin exposure. Conclusions: This study documents extensive surface contamination and skin exposure, including under gloves, to aliphatic polyisocyanates during painting and paint mixing tasks in auto body shop workers. Contaminated surfaces and aerosol deposition during spray painting may both contribute to skin exposure. The colorimetric indicator is a quick, practical and low-cost, but not highly sensitive, industrial hygiene tool to detect isocyanate surface contamination and skin exposures following the use of isocyanate-containing products. [ABSTRACT FROM AUTHOR]