Workplace Exposure Research Articles

Risk assessment of exposure to COVID-19 virus: a cross-sectional study among health-care workers

PurposeHealth-care workers (HCWs) are at increased risk of exposure to the COVID-19 virus, which necessitates implementing transmission prevention measures in health-care delivery facilities, particularly hospitals. This study aims to assess COVID-19 risk in a health-care setting and recommend managerial strategies to cope with existing risk procedures.Design/methodology/approachThis cross-sectional study was conducted among HCWs working in a general hospital in Qazvin, northwest of the country. A total of 310 employees working at different clinical and non-clinical occupational levels participated in the study. The WHO COVID-19 risk assessment tool categorised HCWs in high- or low-risk groups exposed to COVID-19 infection.FindingsFindings revealed statistically significant relationships between workplace exposure to the COVID-19 virus and variables, including job type, performing the aerosol-generating procedure, access to personal protective equipment (PPE) and being trained on Infection Prevention and Control (IPC) guidelines (p < 0.05). HCWs older than 36 years were at 8% more risk of COVID-19 virus. Being a medical doctor or delivering health-care services as a nurse were relatively 28% and 32% times more likely to be at high risk of infection than other hospital staff categories. Having inadequate access to PPE and lack of training on IPC guidelines were also key determinants of high-risk infection.Originality/valueAs most cases at risk of COVID-19 infection belonged to frontline health-care staff in older age groups, this study recommend limiting the exposure of vulnerable staff to COVID-19 patients, increasing protective measures for HCWs and providing essential information about infection control procedures.

Mat-O-Covid: Validation of a SARS-CoV-2 Job Exposure Matrix (JEM) Using Data from a National Compensation System for Occupational COVID-19.

Background. We aimed to assess the validity of the Mat-O-Covid Job Exposure Matrix (JEM) on SARS-CoV-2 using compensation data from the French National Health Insurance compensation system for occupational-related COVID-19. Methods. Deidentified compensation data for occupational COVID-19 in France were obtained between August 2020 and August 2021. The case acceptance was considered as the reference. Mat-O-Covid is an expert-based French JEM on workplace exposure to SARS-CoV-2. Bi- and multivariable models were used to study the association between the exposure assessed by Mat-O-Covid and the reference, as well as the area under the curve (AUC), sensitivity, specificity, predictive values, and likelihood ratios. Results. In the 1140 cases included, there was a close association between the Mat-O-Covid index and the reference (p < 0.0001). The overall predictivity was good, with an AUC of 0.78 and an optimal threshold at 13 per thousand. Using Youden’s J statistic resulted in 0.67 sensitivity and 0.87 specificity. Both positive and negative likelihood ratios were significant: 4.9 [2.4–6.4] and 0.4 [0.3–0.4], respectively. Discussion. It was possible to assess Mat-O-Covid’s validity using data from the national compensation system for occupational COVID-19. Though further studies are needed, Mat-O-Covid exposure assessment appears to be accurate enough to be used in research.

Analysis of Mortality from Asbestos-Related Diseases in Brazil Using Multiple Health Information Systems, 1996–2017

BackgroundIn Brazil, asbestos was intensively used from the 1960s until its ban in 2017. Mesothelioma, asbestosis, and pleural plaques are typical asbestos-related diseases (ARD-T). To create an ARD-T national database, death records from 1996–2017 were retrieved from several health information systems (HIS). MethodsAll national HIS containing coded diagnoses (ICD-10) and death information were obtained. Linkage was performed to create a single database of ARD-T death records, either as underlying or contributory causes, in adults aged 30 years and older. ResultsA total of 3,057 ARD-T death records were found, 2,405 (76.4%) of which being malignant mesotheliomas (MM). Pleural MM (n = 1,006; 41.8%) and unspecified MM (n = 792; 32.9%) prevailed. Male to female MM ratio (M:F) was 1.4:1, and higher ratios were found for non-malignant ARD-T: 3.5:1 for asbestosis and 2.4:1 for pleural plaques. Male crude annual mesothelioma mortality (CMmm x1,000,000) was 0.98 in 1996 and 2.26 in 2017, a 131.1% increment, while for females it was 1.04 and 1.25, a 20.2% increase, correspondingly. The small number of deaths with asbestosis and pleural plaques records precluded conclusive interpretations. ConclusionsEven with the linkage of several HIS, ARD-T in death records remained in low numbers. MM mortality in men was higher and showed a rapid increase and, along with non-malignant ARD-T, higher M:F ratios suggested a predominant pattern of work-related exposure. The monitoring of workplace and environmental asbestos exposure needs to be improved, as well as the workers surveillance, following the recent Brazilian ban.

Investigation of a cluster of Legionnaires' disease during the outbreak of coronavirus disease 2019 pandemic in northeastern Taiwan, June 2021.

PurposeTo describe the investigation and intervention of a cluster of Legionnaires’ disease detected during the outbreak of coronavirus disease 2019 (COVID-19) pandemic.MethodsFrom June 7 to 22, 2021, 15 cases in the neighborhood near our hospital were detected. Information about residence, workplace, hospital visit, and potential exposures was collected. Sampling and decontamination were performed for potential sources.ResultsAll 15 patients had pneumonia when visiting the emergency room with negative COVID-19 test results. Most patients were male (73.3%) with the mean age of 65.7 years. The most common comorbidities were diabetes mellitus (40.0%) and hypertension (40%). The most common symptom was fever (93.3%). Two (13.3%) patients needed mechanical ventilators. Fever subsided within 2 days of treatment for most cases (85.7%). Five cases had exposure history at our hospital, and the other 10 lived or worked in the area within 2 km of our hospital, mostly in buildings A and B. Water sampling was carried out for our hospital, buildings A and B; one water sample from a cooling tower in our hospital cultured positive for Legionella bacteria. Early testing and treatment for suspected cases were carried out for the outbreak, and all cases were discharged with pneumonia resolution.ConclusionThis was a community outbreak of Legionnaires' disease near our hospital. COVID-19 tests were repeated frequently before testing for Legionnaires' disease during the COVID-19 pandemic. Early recognition of Legionnaires’ disease and timely treatment improved outcome.

Occupational risk assessment of organophosphates with an emphasis on psychological and oxidative stress factors.

Organophosphate pesticides (OPPs) are widely used all over the world in domestic and industrial settings, but these chemicals affect the nervous system, induce suicidal thoughts, depression and anxiety, and impair sleep quality. The purpose of this study was to investigate the relationship between the main toxicity mechanisms of OPPs, oxidative stress and cholinesterase inhibition, and psychological parameters in chronic exposure to OPPs. This cross-sectional study was conducted on 56 male OPPs factory workers as the worker group and 47 unexposed individuals within the same age range as the control group. Psychological factors were assessed using validated questionnaires. The activity of plasma cholinesterase and oxidative stress biomarkers, total antioxidant capacity of plasma, lipid peroxidation (LPO), and protein carbonylation were determined in blood samples by spectrophotometer. Sleep quality score in the factory workers was lower, and depression and suicidal ideation scores were higher than those in the control group. These factory workers showed 35% lower levels of plasma cholinesterase activity than did the controls. Compared to the control group, a significant impairment in oxidative stress biomarkers was also observed in the workers. Meanwhile, there was a significant relationship between the duration of employment and the level of LPO as well as a significant correlation between the quality of sleep and plasma cholinesterase in the workers. In conclusion, long-term exposure to OPPs could cause oxidative damages and neurobehavioral effects. The close monitoring of workplace exposure to organophosphates pesticides and also their respective solvents along with the reduction of working hours are of the necessities to avoid the adverse impacts of exposure to these pesticides.

Demographic, exposure and clinical characteristics in a multinational registry of engineered stone workers with silicosis

ObjectivesTo investigate differences in workplace exposure, demographic and clinical findings in engineered stone (ES) workers from a multinational consortium using the Engineered Stone Silicosis Investigators (ESSI) Global Silicosis Registry.MethodsWith ethics...

Exposure assessment of polycyclic aromatic hydrocarbons in refined coal tar sealant applications.

Refined coal tar sealant (RCTS) emulsions are used to seal the surface of asphalt pavement. Nine of the 22 polycyclic aromatic hydrocarbons (PAHs) evaluated in this study are classified as known, probable, or possible human carcinogens. Exposure assessment research for RCTS workers has not been published previously. The overall objective of this study was to develop a representative occupational exposure assessment of PAH exposure for RCTS workers based on worksite surveys. The specific aims were to: 1) quantify full-shift airborne occupational exposures to PAHs among RCTS workers; 2) quantify workers' dermal exposures to PAHs; 3) quantify biomarkers of PAH exposure in workers' urine; 4) identify specific job titles associated with RCTS exposure; and 5) apply these results to a biological exposure index to assess risk of potential genotoxicity from occupational exposures. A total of twenty-one RCTS workers were recruited from three companies. Personal and area air samples were collected using a modification of NIOSH Method 5515. Dermal exposure was assessed by hand and neck wipes before and after shifts. Twenty-two PAHs were quantified via gas chromatography-mass spectrometry selected ion monitoring. Internal dose was estimated by quantifying select PAH metabolites in pre- and post-shift urine samples using on-line solid phase extraction-high performance liquid chromatography-tandem mass spectrometry. PAH levels in the worker breathing zones were highest for naphthalene, acenaphthene, and phenanthrene, with geometric means of 52.1, 11.4, and 9.8μg/m3, respectively. Hand wipe levels of phenanthrene, fluoranthene and pyrene were the highest among the 22 PAHs with geometric means of 7.9, 7.7, and 5.5μg/cm2, respectively. Urinary PAH biomarkers for naphthalene, fluorene, phenanthrene, and pyrene were detected in all workers and were higher for post-shift samples than those collected pre-shift. Urinary concentrations of the metabolite 1-hydroxypyrene were greater than the American Conference of Governmental Industrial Hygienists (ACGIH) Biological Exposure Index (BEI) for this metabolite in 89 percent of post-shift samples collected on the final day of the work week or field survey. Statistically significances were found between concentrations of fluorene, naphthalene, and phenanthrene in the breathing zone of workers and their corresponding urinary PAH biomarkers. Workers were placed in two work place exposure groups: applicators and non-applicators. Applicators had higher total PAH concentrations in personal breathing zone (PBZ) air samples than non-applicators and were more likely to have post-shift hand wipe concentrations significantly higher than pre-shift concentrations. Concentrations of post-shift urinary biomarkers were higher, albeit not significantly, for applicators than non-applicators. The exposure results from RCTS worker samples cannot be explained by proximal factors such as nearby restaurants or construction. Air and skin concentration levels were substantially higher for RCTS workers than previously published levels among asphalt workers for all PAHs. PAH profiles on skin wipes were more consistent with RCTS sealant product than air samples. Last day post-shift urinary concentrations of 1-hydroxypyrene greatly exceeded the ACGIH BEI benchmark of 2.5μg/L in 25 of 26 samples, which suggests occupational exposure and risk of genotoxicity. When pyrene and benzo[a]pyrene were both detected, concentration ratios from personal exposure samples were used to calculate the adjusted BEI. Concentrations of 1-hydroxypyrene exceeded the adjusted BEIs for air, hand wipes, and neck wipes in most cases. These results indicate the need to increase safety controls and exposure mitigation for RCTS workers.

Estimating cobalt exposure in respirable dust from cobalt in inhalable dust.

Cobalt is a commonly used element in metal industry. Exposure to workers occurs mainly by inhalation of cobalt-containing dust. For the evaluation of cobalt exposure, risk assessment and investigations on occupational diseases, measurements of cobalt in respirable dust are needed. Up to now, often only data for cobalt in inhalable dust are available, which is due to the earlier classification of the limit value in this fraction. Therefore, a possibility to convert cobalt concentrations mathematically from inhalable into respirable concentrations is desirable. In this study, 639 parallel measurements of cobalt concentrations in inhalable (cI(Co)) and respirable dust fractions (cR(Co)) were extracted from the non-public exposure database MEGA (Measurement data relating to workplace exposure to hazardous substances, maintained at the Institute for Occupational Safety and Health of the German Social Accident Insurance) and investigated by regression analysis. For the whole dataset regression shows high quality measures (correlation coefficient R=0.888, adjusted coefficient of determination adj. R2=0.788 - R2 is adjusted to sample size). Further description of the data is achieved by splitting the dataset according to the type of sampling ('stationary' and 'personal') and three working activity groups, 'high temperature processing', 'filling/transport/storage', and 'machining/abrasive techniques' (0.845 ≤ R≤0.876; 0.711 ≤ adj. R2 ≤ 0.762). As subgroups of 'high temperature processing' and 'machining/abrasive techniques' two further groups could be determined. These groups are called heuristic groups, since they have to be formed non-systematically by trial and error. These heuristic groups are 'welding' and 'grinding'. They are more selective on the included working activities with adj. R2 of 0.703 and 0.748 respectively. The resulting conversion functions of all groups are power functions with exponents between 0.704 and 0.794. For the estimation of cobalt in respirable dust in other studies, it is possible to use the conversion functions of the heuristic and working activity groups. Limitations of the possibility to use the conversion functions are discussed.

The Role of Clinical Leaders in Workforce Development and Retention in Post-Acute and Long-Term Care

The Role of Clinical Leaders in Workforce Development and Retention in Post-Acute and Long-Term Care

Workplace Trauma in a Digital Age: The Impact of Video Evidence of Violent Crime on Criminal Justice Professionals.

High-quality video and audio recordings of violent crimes, captured using now ubiquitous digital technologies, play an increasingly important role in the administration of justice. However, the effects of exposure to gruesome material presented in this form on criminal justice professionals who analyze, evaluate, and use this potentially traumatic content in the context of their work, are largely unknown. Using long interviews and constructivist grounded theory, this qualitative study sought to explore experiences of exposure to video evidence of violent crime among Canadian criminal justice professionals. Sixteen individuals including police, lawyers, judges, psychiatrists, law clerks, and court reporters volunteered to participate in qualitative long interviews asking about workplace exposures to violent videos. Themes identified address the ubiquity of video evidence of violent crime; proximity to violence through video; being blindsided through lack of preparedness for violent content; repeated exposures through multiple and protracted viewings; insufficient customary methods for self-protection; and the enduring impact of exposure to videoed violence. We determine that criminal justice professionals are increasingly and repeatedly presented with deeply disturbing imagery that was once imperceptible or unknowable and thus previously held at a greater distance. Elements of what is newly visible and audible in video evidence of violent crime create a new emotional proximity to violence that potentially increases the risks of secondary trauma and underscores the need for improved safety measures.

Job-Exposure Matrix: A Useful Tool for Incorporating Workplace Exposure Data Into Population Health Research and Practice.

Workplace exposures to physical, chemical, and psychosocial factors account for a large burden of chronic diseases. Obtaining useful estimates of current and past workplace exposures is challenging, particularly in large general population studies. Job-exposure matrices (JEMs) are a useful tool for exposure assessment, particularly when no individual level exposure data are available. A JEM provides a cross-tabulation of job titles (sometimes combined with industry) and estimated exposures to workers carrying out these jobs during different time periods. The major limitation of JEMs is that they do not account for individual variation in exposures within the same job. This limitation is offset by the advantages of low cost, wide applicability, lack of bias from self-reporting, and the ability to estimate exposures based on job titles when no other exposure data exist. There is growing use of JEMs in research examining the role of workplace exposures in the development of chronic diseases, and interest in their application to public health practice. This paper provides a scoping review of JEM use, some examples of JEMs, and brief guidance for the application of JEMs in epidemiological research. In conclusion, JEMs provide a useful tool for researchers and public health practitioners to estimate occupational exposures in large scale epidemiological studies relevant to many health conditions.

TSCA risk evaluation-directed characterization of occupational exposures during formaldehyde manufacturing, use as an intermediate, and compounding of formaldehyde-based polymers

In 2020, the U.S. EPA initiated TSCA risk evaluations for 20 High Priority chemicals, as required by the Lautenberg Act. In addition to consumer exposures, the evaluations include quantitative assessments of worker exposures, hazards and risk. The EPA evaluations of worker exposures, and authority over corrective action to address unacceptably high workplace exposures, overlap OSHA's authority for regulating workplace exposures. This dual federal regulatory authority for risk evaluation and risk management, presents new challenges for industrial hygienists, exposure/risk assessors, and risk managers. One of the chemicals identified as High Priority by the EPA is formaldehyde. In response to these challenges, Celanese supplemented its regular OSHA compliance sampling for formaldehyde with a one-time comprehensive sampling at our sole U.S. formaldehyde manufacturing facility. The sampling characterized all worker populations at the facility, including office workers. Although the EPA assessment is ongoing and may reach different conclusions related to an acceptable exposure limit, 126 full-shift monitoring results demonstrated compliance with the OSHA Formaldehyde Standard (29 CRF 1910.1048) for health protection. Methodologies used to identify workers for exposure monitoring, to characterize multiple EPA-specified worker populations, as well as potential challenges related to the dual regulatory authority for assessing and managing worker exposures are discussed.

Silica and Connective Tissue Disorders: The Important Role of the Dermatologist

Dermatological manifestations of connective tissue diseases (CTDs) are common and frequently precede other symptoms. Thus, dermatologists may be the first clinicians to diagnose these disorders. Silica exposure is an acknowledged cause of several CTDs, but this is under-appreciated by clinicians, who may also be unaware of the wide range of jobs in which silica exposure can occur. The CTDs associated with silica exposure include systemic sclerosis (SSc), rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), anti-neutrophil cytoplasmic antibody (ANCA) positive vasculitis and overlap syndromes. Silica-related systemic sclerosis (Si-SSc) is associated with a specific antibody profile and more severe disease. Silicosis has re-emerged worldwide recently due to several new workplace exposures, including a new type of silicosis (artificial stone (AS) silicosis), which is associated with a particularly high rate of auto-antibody formation. Dangerous work practices are still occurring. This article summarises recent literature on the topic of the resurgence of silicosis and silica-induced CTDs and reminds dermatologists of the importance of taking a thorough occupational history in all patients. Early intervention in CTDs and reduction in dust exposure can reduce risk and improve prognosis. Treatment options are rapidly improving.

The Gendered Outbreak of COVID-19 in South Korea

ABSTRACT Although South Korea is well-known for its aggressive response to COVID-19, little is known about how the risk of infection manifests differently by gender. Using real-time data on confirmed cases, this study empirically examines the gendered outbreak of COVID-19 driven by occupational segregation in South Korea. It investigates gender differences in risk of work-related exposure, particularly for those jobs where essential activities are conducted, such as in the healthcare sector, and that are dominated by women. The results from the multinomial logit model confirm that women have a higher risk of workplace exposure than men, particularly in pink-collar and care jobs. The findings emphasize the need for a gender-aware perspective to policy measures advanced during the pandemic and recovery. HIGHLIGHTS Gender is an important factor for determining infection risks of COVID-19 in workplaces. In South Korea’s gender-segregated labor markets, women have higher exposure to infection than men. Women typically occupy jobs in the healthcare and welfare sectors that require frequent interpersonal interaction. They are also underrepresented in occupations with the ability to telecommute. Policy measures must include gender-aware responses and address inequality during the pandemic and recovery.

Reported exposure trends among healthcare personnel COVID-19 cases, USA, March 2020–March 2021

BackgroundHealth care personnel (HCP) have experienced significant SARS-CoV-2 risk, but exposure settings among HCP COVID-19 cases are poorly characterized. MethodsWe assessed exposure settings among HCP COVID-19 cases in the United States from March 2020 to March 2021 with reported exposures (n = 83,775) using national COVID-19 surveillance data. Exposure setting and reported community incidence temporal trends were described using breakpoint estimation. Among cases identified before initiation of COVID-19 vaccination programs (n = 65,650), we used separate multivariable regression models to estimate adjusted prevalence ratios (aPR) for associations of community incidence with health care and household and/or community exposures. ResultsHealth care exposures were the most reported (52.0%), followed by household (30.8%) and community exposures (25.6%). Health care exposures and community COVID-19 incidence showed similar temporal trends. In adjusted analyses, HCP cases were more likely to report health care exposures (aPR = 1.31; 95% CI:1.26-1.36) and less likely to report household and/or community exposures (aPR = 0.73; 95% CI:0.70-0.76) under the highest vs lowest community incidence levels. DiscussionThese findings highlight HCP exposure setting temporal trends and workplace exposure hazards under high community incidence. Findings also underscore the need for robust collection of work-related data in infectious disease surveillance. ConclusionsMany reported HCP cases experienced occupational COVID-19 exposures, particularly during periods of higher community COVID-19 incidence.

Maternal occupational exposures and fetal growth in a Spanish birth cohort.

While the epidemiologic literature suggests certain maternal occupational exposures may be associated with reduced measures of size at birth, the occupational literature employing fetal biometry data to assess fetal growth is sparse. The present study examines associations between maternal occupational exposures and ultrasound-measured fetal growth. We included 1,739 singleton pregnancies from the INfancia y Medio Ambiente (INMA) project (2003-2008). At 32 weeks of pregnancy, interviewers ascertained mothers’ employment status and assessed job-related physical loads, work schedules, and job strain during pregnancy. Job titles were linked to a job-exposure matrix to estimate exposure to 10 endocrine disrupting chemical (EDC) groups. We calculated z-scores from longitudinal growth curves representing trajectories from 0-12, 12-20 and 20-34 gestational weeks for abdominal circumference (AC), biparietal diameter (BPD), femur length (FL), and estimated fetal weight (EFW). Linear mixed models clustered by IMNA region (i.e., Gipuzkoa, Sabadell, Valencia) were used to examine associations between occupational exposures and fetal growth. Effect estimates are presented as percentage change in fetal growth. There was limited evidence of associations between work-related non-chemical stressors and fetal growth. We observed associations of similar magnitude between multiple EDC groups and decreased EFW trajectories during 20-34 gestational weeks (phthalates: -1.4% [-3.5, 0.6%]; alkylphenolic compounds (APCs): -1.1% [-2.3, 0.1%]; miscellaneous chemicals: -1.5% [-3.7, 0.8%]), while miscellaneous chemicals were associated with increased BPD from 12-20 weeks (2.1% [0.8, 3.5%]). Notably, 67% of women exposed to phthalates were hairdressers; 68% of women exposed to APCs worked as domestic cleaners. In conclusion, we found limited evidence that maternal occupational exposures impact fetal growth. Further research should consider the combined impact of multiple workplace exposures.

PREVALENCE AND PREDICTORS OF POSTTRAUMATIC STRESS DISORDER, DEPRESSION, AND ANXIETY IN PERSONNEL WORKING IN EMERGENCY DEPARTMENT SETTINGS: A SYSTEMATIC REVIEW

BackgroundProfessionals working in the emergency department (ED) are regularly exposed to traumatic events. Rates of posttraumatic mental health conditions vary widely in the literature and there is no agreement that rates in ED staff are elevated relative to other populations. ObjectiveWe conducted a systematic review of international literature reporting prevalence of posttraumatic stress disorder (PTSD), depression, and anxiety in ED personnel to determine whether prevalence is elevated compared to the general community, and to evaluate convergent evidence across the literature for predictive factors. To our knowledge, there is no comprehensive review on this topic in the literature at this time. Methods: Seven databases were searched for studies reporting rates of PTSD, depression, and anxiety in ED personnel. Two independent researchers screened studies and assessed quality using Munn's Prevalence Critical Appraisal Instrument. Best-evidence synthesis determined whether conditions demonstrated elevated prevalence compared to the general population of Canada, a conservative benchmark. ResultsTwenty-four studies from 12 countries and a combined sample size of 4768 were included. PTSD rates ranged from 0% to 23.6% (mean 10.47%), depression ranged from 0.7% to 77.1% (mean 24.8%), and anxiety rates ranged from 2.4% to 14.6% (mean 9.29%). Each condition was elevated compared to the general population. Sociodemographic variables were not consistent predictors. Elevated PTSD seemed most strongly related to workplace exposure and maladaptive coping. ConclusionsED professionals have an elevated risk of experiencing PTSD, depression, and anxiety. Identification of organizational and workplace predictors are needed to inform interventions that will reduce risk and provide optimal treatment and management of PTSD, depression, and anxiety in ED settings.

Health effects of exposure to isocyanates in a car factory.

Isocyanates are known to induce occupational diseases. The aim of this work was to assess the health effects of exposure to isocyanates and to test the sensitivity of selected parameters for early detection of isocyanate-related allergic diseases. In total, 35 employees from one factory were tested: 26 workers exposed to isocyanates (exposed group) and nine office workers (control group). All subjects filled in a questionnaire regarding possible health problems. Fractional exhaled nitric oxide (FeNO) and spirometry were measured for each subject at the same time during two consecutive working days. A urine sample was taken for a biological exposure test (BET). No significant difference was found between the exposed and control groups for spirometry parameters and FeNO. However, in the exposed group, FeNO was highly elevated (> 50 ppb) in five subjects (all reporting health problems at the workplace, all with normal spirometry and non-smokers). The BET revealed a significant difference (p < 0.001) between the exposed and control groups for 4,4´-methylenediphenyl diamine (MDA) in the urine. Our examination showed the usefulness of the BET in monitoring of workplace exposure to isocyanates and the importance of FeNO in monitoring of allergic inflammation of airways in non-smoking employees with normal spirometry.

On-Site Deployment of an Air-Liquid-Interphase Device to Assess Health Hazard Potency of Airborne Workplace Contaminants: The Case of 3-D Printers.

Biomonitoring of workers is an approach of evaluating workers’ exposure to chemicals and particulate matter by measuring biomarkers of parent chemicals, their metabolites, and reaction products in workers’ biospecimens. Prerequisites for biological monitoring in the workplace include permission to enter the workplace, approval of the study plan from the IRB (Institutional Review Board), and obtaining consent from workers. Because of the complex legal process involved in biomonitoring, few studies have been conducted so far on biomonitoring of workers’ exposures to nanoparticles and other hazards from emerging materials and advanced nanotechnologies. We have developed a cell-based biomonitoring device that can evaluate acute cytotoxicity and various other effect biomakers, such as inflammation, at realistic workplace exposure. This device is based on air–liquid interphase (ALI) and can be used to evaluate cell toxicity and early effect biomarkers along adverse outcome pathways. Following exposure of A549 lung epithelial cells in ALI to workplace air for 1–2 h, the cells were processed to assess the induction of inflammatory and cell damage biomarkers. Initially, we estimated the deposition rate of nanoparticles in the transwell by exposing the cell-free ALI device to silver nanoparticle aerosols (AgNP 20–30 nm) for 2 h in the laboratory. Then A549 lung epithelial cells cultured on the transwell in the ALI device were exposed to AgNP nanoaerosols for 2 h and evaluated for cytotoxicity and induction of mRNAs of pro-inflammatory cytokines IL-1b, IL-6, and TNF-α. Then the cells in the ALI device were exposed to 3-D printer emissions at the workplace and evaluated for the same matched endpoints. The mRNA levels for IL-1b, IL-6, and TNF-α increased significantly at the end of 2-h exposure of A549 cells to the positive control AgNP aerosols. These mRNAs, as well as LDH and microprotein concentrations, increased even more after 24-h post-exposure incubation (p < 0.05). Cytotoxicity evaluation of 3-D printer emissions at 810 and 957 μg/m3, which was more than 80 times higher than the airborne total suspended particulate concentrations in the workplace air (9–12.5 μg/m3), suggested no significant acute cytotoxicity at the end of 2-h exposure to 3-D-printing emission, as well as at 24-h post-exposure incubation. Hyperspectral microscopic observation showed that 3-D printers emitted particles to be attached to A549 cells after 2-h exposure, and many particles were internalized by A549 cells after 24 h of post-exposure incubation. The mRNA expression of pro-inflammatory cytokine IL-1b and IL-6 increased significantly after 2-h exposure to 3-D printer emissions and after 24-h incubation (only IL-6). In contrast, the expression of TNF-α mRNA decreased significantly after 2 h of exposure to 3-D printers and decreased even more after 24-h post-exposure incubation. These results support the use of cell-based ALI devices for direct assessment of airborne hazards in the workplace, for probing toxicological properties of airborne contaminants using adverse molecular pathways, and for guiding study design for workplace biomonitoring. ALI devices can bridge conventional exposure assessment with cellular toxicity testing platforms for hazard and risk assessment.

The National Occupational Respiratory Disease Registry (NORDR): it is time to learn from failure.

The National Occupational Respiratory Disease Registry (NORDR): it is time to learn from failure.