Journal of Occupational and Environmental Hygiene最新文献

Antineoplastic drug (AD) exposure can cause adverse health effects for healthcare workers. AD contamination on surfaces persists despite interventions to reduce it. The United States Pharmacopeial Convention recommends surface sampling as a measure of exposure control but does not offer guidance regarding specific ADs, surfaces in patient care areas, or size of surface area to sample. This scoping review of literature published since January 1, 2004 aimed to identify specific surfaces in patient care areas which were tested and found to be contaminated with ADs. The authors describe (a) which ADs were assessed, (b) the percent of surfaces contaminated; and sizes of sampling areas for surface testing, and (c) whether personal protective equipment (PPE) or closed system transfer devices (CSTDs) were utilized to reduce healthcare worker exposure and AD surface contamination. The majority of studies were conducted in North America or Europe. The most common location for testing was hospitals. Most studies sampled for one to three marker drugs of interest, with cyclophosphamide being the most common. Most studies utilized a standardized surface area with 100 to 900 cm² being the most common. Time of day varied, but most sampling was conducted at the end of the workday before cleaning. Gas chromatography-tandem mass spectrometry (GC-MSMS) and liquid chromatography-tandem mass spectrometry (LC-MSMS) were the most frequent analytical methods used. Contamination was found most often on floors, nursing counters, armchairs, intravenous (IV) poles/pumps, patient tables, hazardous drug (HD) waste containers, doorknobs/handles, storage shelves, bathroom surfaces, HD vials/bags, and telephones. PPE and CSTD use were not consistently reported. Based on this review, the authors make several recommendations for the standardization of data collection and reporting of findings. Key among these is the need to measure and report data on the use of PPE and CSTDs to modify environmental contamination and, critically, healthcare worker exposure to ADs.

Laser photometers provide real-time data on airborne aerosols. They are a valuable tool for assessing task exposures, as well as process and environmental changes. However, their performance compared to the validated National Institute of Occupational Health and Safety (NIOSH) method Particulates Not Otherwise Regulated, Respirable 0600 gravitational method is uncertain. NIOSH has established a criterion for sampling and analytical methods to be within 25% of the 'true' concentration. Manufacturers and research scientists cite the importance of using an aerosol-specific calibration factor to improve instrument correlation with the gravimetric method. Field data from three photometers are presented to illustrate instrument performance variability and evaluate single and averaged aerosol-specific calibration factors. Respirable particulate and respirable crystalline silica (RCS) were simultaneously measured ten times in an operating rock crushing facility using the NIOSH methods 0600 and 7500 Silica, Crystalline, by XRD (filter redeposition) and three factory calibrated photometers. Ten aerosol-specific calibration factors were calculated for each photometer and used to determine single and averaged aerosol-specific calibration factors. Single and averaged aerosol-specific calibration factors were mathematically applied to "correct" the factory calibrated instrument measurements. Performance was evaluated using absolute relative error. With the factory calibration, the average absolute relative error for each instrument exceeded 25%. A single-event aerosol-specific calibration factor reduced the average absolute relative error for all instruments, bringing it below 25% for one of the three photometers. A 3-run average aerosol-specific calibration factor reduced the average absolute relative error below 25% for all instruments. Further averaging of calibration factor provided no significant advantage. The 95th percentile of absolute error fell below 25% for one of the tested instruments when applying both a single and averaged calibration factor but remained above 25% for the other two instruments. Field testing of the single-run, three-run average and ten-run average calibration factors revealed that the absolute relative error exceeded 25% in at least one of the three CF-field tests for each instrument. The average absolute relative error in estimates of RCS varied from 7 to 38%.

A safety officer (SO) can assist healthcare workers in minimizing respiratory transmission of communicable diseases through verification of compliance with safety protocols, such as appropriately donning and doffing personal protective equipment (PPE). This project sought to determine if observation of PPE donning and doffing for detection of protocol violations by a virtual safety officer (VSO) was a feasible option to improve the safety of the workplace. Five healthcare workers with experience serving as safety officers were enrolled in a feasibility study in which they observed actors donning and doffing PPE in-person and noted errors using a curated checklist for documentation. One month later, the same participants viewed recordings of the in-person sessions and again recorded errors for seven trials. Five hundred and twenty-three responses recorded from the SOs across the in-person and virtual trials aligned 88.7% of the time. SOs were more accurate in the virtual setting than in the in-person setting (87.6% vs. 82.4%, respectively). However, Cohen's kappa showed lower inter-rater reliability when observing virtually than in-person, especially in the doffing steps of the protocol. A VSO may be a feasible option when assessing whether participants can correctly follow PPE donning and doffing protocols. Future work includes incorporating real-time observation, 360-degree cameras, virtual reality (VR), and augmented reality (AR) to increase visualization, thereby increasing inter-rater reliability.

In US coal mines, the continuous personal dust monitor (CPDM) is frequently used to determine miners' exposure to respirable dust. Capabilities to analyze the respirable crystalline silica (RCS) content of that dust are needed, but the CPDM sample collection substrate ("stub") interferes with direct analysis. To overcome this challenge, a three-step method is proposed to recover the dust from the stub, deposit the dust on a polyvinyl chloride (PVC) filter, and analyze the recovered dust by Fourier Transform Infrared Spectroscopy (FTIR) to determine the quartz content (as a proxy for RCS). Recent work has established procedures for the latter two steps using representative dust samples suspended in isopropyl alcohol (IPA). That work is extended in the current study to also address the dust recovery step, testing both IPA and deionized water (H₂O) as recovery liquids. Here, blank CPDM stubs were subjected to the entire three-step method and results were used to establish a quartz mass correction for residue that is recovered from the stub itself. Then, the method and correction were applied to lab-spiked and field CPDM stubs. For spiked samples, predicted and expected quartz mass values were highly correlated (R² values >0.97 regardless of recovery liquid or application of the blank CPDM-stub correction); though predicted values were consistently lower than expected values (regression line slopes between 0.84 and 0.86), which might be related to effects of total recovered sample mass on the deposition pattern achieved on PVC filter. For the field samples, IPA proved to be a much more efficient recovery liquid than H₂O. Unfortunately, the evaluation of the predicted quartz mass results on the field samples was confounded by apparent issues with reference filter samples intended to determine expected values.

Differences in escape respirator design can influence the wearer's ventilatory response and impact inspired oxygen (O₂) and carbon dioxide (CO₂) concentrations. There has been minimal investigation into the differences between hood and mask designs as escape respirators that compare between the ventilatory responses of wearing either a hood or mask escape respirator with an identical nose-cup. Thirty-nine healthy young males participated in the study. Each subject participated in two 20-min sessions of monitored breathing, wearing either a hood-type filtering facepiece respirator "CAPS 2000" (Shalon Chemical Industries, Israel & Supergum Industries Ltd, Israel) or an "Orange Diamond" filtering facepiece mask-type escape respirator (DEA Mop, Israel). Inspired gas concentrations of CO₂ and O₂ as well as the ventilatory response were recorded through a nose-cup during the test. Inspired CO₂, minute ventilation, breathing frequency, and the index of central ventilatory drive (V_T/T_I) were all significantly higher (p < 0.05) while wearing a mask respirator compared to a hood respirator. The hood respirator evaluated in the present study outperformed the mask respirator in most indices when measured at rest. The hood respirator had a reduced ventilatory demand compared to the mask respirator and may be advantageous for individuals with weaker respiratory systems, such as the elderly or those who suffer from respiratory diseases.

Agricultural work is one of the highest-risk U.S. occupations for heat-related illness (HRIs). Some tall-growing crops can block the cooling effects of wind or contribute to environmental humidity creating warm and humid microclimates (environments directly surrounding workers). The purpose of this study was to assess the differences in environmental heat stress within the center of tall-growing crop fields compared to the field perimeter. In the summer of 2023, two heat stress monitors collected daily measurements of wet bulb globe temperature (WBGT) in sweet corn and tobacco fields; results support that WBGT was higher at the field center of sweet corn and significantly higher at the field center of tobacco: 6.7% more hours in sweet corn and 13.6% more hours in tobacco were considered unsafe heat stress risk levels at the field center when compared to unsafe hours at the field perimeter. Unsafe heat stress risk levels were more likely to occur in the afternoons in the corn field while a high majority of all recorded hours in tobacco were considered unsafe, including the morning hours. The risk of laboring inside tall crop rows and heat-related illness should be considered in worker education and heat stress plans.

More than 55 years ago, an analytical method employing phase contrast optical microscopy was developed for the quantitative estimation of airborne asbestos fiber concentration, and it was found that the detection limit of these microscopes was dependent upon microscope design, microscope set-up, and observer performance. In the early 1980s, the HSE/NPL Mark II Phase Contrast Test Slide was developed which facilitated standardizing detection limits of microscopes and observers in laboratories around the world. This paper describes the development and testing of an alternative test slide, known as the Pickford Phase Contrast Test Slide, which employs state-of-the-art nano-fabrication technology. Each Pickford Test Slide is certified by the Environmental Analysis Laboratory of the Southern Cross University stating that it is equivalent in performance to that of the HSE/NPL Mark II test slide, which aligns with the United Kingdom Health and Safety Executive HSG248 Asbestos: The Analysts' Guide (2021) requirement. Users report that the Pickford Test Slide is much easier to use than the HSE/NPL Slide. Since the early 1980s, the certification of phase contrast microscope test slides has been based on subjective visibility testing, which is less than ideal because of variations between certifiers, reference standards, and microscopes. Hence, a unique objective visibility test was developed with the aim of replacing subjective testing, and also of conducting routine testing of the test slide phase objects following nano-fabrication. Routine testing has been useful because each Pickford Test Slide is tested and documented so that intricate nano-fabrication chip processes can be controlled over years of production. However, thousands of comparisons of both forms of testing have shown that it is very unlikely that objective visibility testing will ever replace subjective testing because valid and relevant objective testing depends upon standardizing several dozen microscope camera set-up parameters that vary from one camera to another. Further, because the ultimate use of a test slide has always been based on human visibility, validation may not be achievable.

Effective decontamination of hospital surfaces is crucial to protect workers from antineoplastic drugs (ADs) since dermal absorption is the main exposure route to these hazardous medicinal products. Sampling after daily cleaning in oncologic settings from a tertiary hospital was initially performed and exhibited low contamination levels; however, cyclophosphamide was still found (up to 957 pg/cm²) above the guidance value (100 pg/cm²) in four locations, evidencing the need to properly assess and update the cleaning protocols. Then, cleaning efficiencies of six solutions and different protocols were evaluated (including, for the first time, four commercial cleaning solutions/disinfectants not designed specifically for AD removal) after deliberate contamination of three model surfaces with 13 pharmaceuticals: bicalutamide, capecitabine, cyclophosphamide, cyproterone, doxorubicin, etoposide, flutamide, ifosfamide, imatinib, megestrol, mycophenolate mofetil, paclitaxel, and prednisone. Wipe sampling and liquid chromatography-tandem mass spectrometry were employed to determine surface contamination after cleaning. Results revealed that: (i) none of the solutions or procedures totally removed all target pharmaceuticals from surfaces; (ii) the removal efficiency increased with cleaning steps (average removals above 90% were attained for Vyclean and Clinell Universal Spray using two cleaning steps); and (iii) the cleaning efficiency was likely favored by the application of the solution/disinfectant directly on the surfaces. Therefore, considering the dissimilar chemical structures and properties of the numerous ADs in use, the cleaning agent and protocol should be adjusted to the reality of each healthcare unit. Still, the scientific community is encouraged to develop a cleaning solution/protocol to simultaneously eliminate/remove as many ADs as possible.

Chemical release data are essential for performing chemical risk assessments to understand the potential exposures arising from industrial processes. Often, these data are unknown or unavailable and must be estimated. A case study of volatile organic compound releases during extrusion-based additive manufacturing is used here to explore the viability of various regression methods for predicting chemical releases to inform chemical assessments. The methods assessed in this work include linear Least Squares, Least Absolute Shrinkage and Selection Operator (LASSO) and Ridge regression, classification and regression tree, random forest model, and neural network analysis. Secondary data describing polymeric extrusion in multiple applications are curated and assembled in a dataset to support regression modeling using default parameters for the various approaches. The potential to add noise to the dataset and improve regression is evaluated using synthetic data generation. Evaluation of model performance for a common test set found all methods were able to achieve predictions within 10%-error for up to 98% of the test sample population. The degree to which this level of performance was maintained when varying the number and type of features for regression was dependent on the model type. Linear methods and neural network analysis predicted the most test samples within 10%-error for smaller numbers of features while tree-based approaches could accommodate a larger number of features. The number and type of features can be important if the desire is to make chemical-specific release predictions. The inclusion of release data from related processes generally improved test set predictions across all models while the use of synthetic data as implemented here resulted in smaller increases in test sample predictions within 10%-error. Future work should focus on improving access to primary data and optimizing models to achieve maximum predictive performance of environmental releases to support chemical risk assessment.