Assessment of emissions and exposure in 3D printing workplaces in Taiwan.

Three-dimensional (3D) printing is an emerging and booming industry in Taiwan. Compared to traditional manufacturing, 3D printing has various advantages, such as advanced customization, additive manufacturing, reduced mold opening time, and reduced consumption of precursors. In this study, the real-time monitoring of particulate matter (PM) and total volatile organic compound (TVOC) emissions from various filaments is investigated using fused deposition modeling with material extrusion technology, a liquid-crystal display, a stereolithography apparatus based on vat photopolymerization technology, and binder jetting for occupational settings. An exposure assessment for nearby workers using the 3D printing process was performed, and improvement measures were recommended. Nine 3D printing fields were measured. The generation rate of ultrafine particles ranged from 1.19 × 1010 to 4.90 × 1012 #/min, and the geometric mean particle size ranged from 30.91 to 55.50 nm. The average concentration of ultrafine particles ranged from 2.31 × 103 to 7.36 × 104 #/cm3, and the PM2.5 and PM10 concentrations in each field ranged from 0.74 ± 0.27 to 12.46 ± 5.61 µg/m3 and from 2.39 ± 0.60 to 30.65 ± 21.26 µg/m3, respectively. The TVOC concentration ranged from 0.127 ± 0.012 to 1.567 ± 0.172 ppm. The respiratory deposition (RDUFPs) dose ranged from 2.02 × 1013 to 5.54 × 1014 nm2/day. Depending on the operating conditions, appropriate control and protective measures should be employed to protect workers' health.

Occupational exposure assessment with solid substances: choosing a vehicle for in vitro percutaneous absorption experiments.

Percutaneous occupational exposure to industrial toxicants can be assessed in vitro on excised human or animal skins. Numerous factors can significantly influence skin permeation of chemicals and the flux determination. Among them, the vehicle used to solubilize the solid substances is a tricky key step. A "realistic surrogate" that closely matches the exposure scenario is recommended in first intention. When direct transposition of occupational exposure conditions to in vitro experiments is impossible, it is recommended that the vehicle used does not affect the skin barrier (in particular in terms of structural integrity, composition, or enzymatic activity). Indeed, any such effect could alter the percutaneous absorption of substances in a number of ways, as we will see. Potential effects are described for five monophasic vehicles, including the three most frequently used: water, ethanol, acetone; and two that are more rarely used, but are realistic: artificial sebum and artificial sweat. Finally, we discuss a number of criteria to be verified and the associated tests that should be performed when choosing the most appropriate vehicle, keeping in mind that, in the context of occupational exposure, the scientific quality of the percutaneous absorption data provided, and how they are interpreted, may have long-range consequences. From the narrative review presented, we also identify and discuss important factors to consider in future updates of the OECD guidelines for in vitro skin absorption experiments.

Emissions and health risks from the use of 3D printers in an occupational setting.

The aim of this study was to determine concentrations of particulates and volatile organic compounds (VOCs) emitted from 3D printers using polylactic acid (PLA) filaments at a university workroom to assess exposure and health risks in an occupational setting. Under typical-case (one printer) and worst-case (three printers operating simultaneously) scenarios, particulate concentration (total and respirable), VOCs and formaldehyde were measured. Air samples were collected in the printing room and adjacent hallway. Size-resolved levels of nano-diameter particles were also collected in the printing room. Total particulate levels were higher in the worst-case scenario (0.7 mg/m3) vs. typical-case scenario (0.3 mg/m3). Respirable particulate and formaldehyde concentrations were similar between the two scenarios. Size-resolved measurements showed that most particles ranged from approximately 27 to 116 nm. Total VOC levels were approximately 6-fold higher during the worst-case scenario vs. typical situation with isopropyl alcohol being the predominant VOC. Airborne concentrations in the hallway were generally lower than inside the printing room. All measurements were below their respective occupational exposure limits. In summary, emissions of particulates and VOCs increased when multiple 3D printers were operating simultaneously. Airborne levels in the adjacent hallway were similar between the two scenarios. Overall, data suggest a low risk of significant and persistent adverse health effects. Nevertheless, the health effects attributed to 3D printing are not fully known and adherence to good hygiene principles is recommended during use of this technology.

Bioelectrical impedance analysis for severe stroke patients with upper extremity hemiplegia.

[Purpose] This study is to analyze bioimpedance parameters and occupational assessment for severe stroke patients with upper extremity hemiplegia. [Subjects and Methods] Experimental subjects were 20 hemiplegic stroke patients receiving rehabilitation therapy between November to October, 2015. Prediction marker (PM), and phase angle (θ), a nd characteristic frequency (fc) were measured using bioelectrical impedance spectroscopy (MultiScan 5000). Bioelectrical impedance vector analysis (BIVA) was also obtained from the bioimpedance data. Then, these values were compared with occupational assessment tools. [Results] A significant differences in PM, θ, fc, and BIVA were observed between paretic region and non-paretic region of 5 severe stroke patients. These results were in good agreement with occupational assessment (pinch and hand grip strength, and ADL by MBI). [Conclusion] There were significant differences in impedance parameters between paretic region and non-paretic region of 5 severe stroke patients with upper extremity hemiplegia. Thus, the BIA could be useful tool for evaluating hemiplegic stroke patients receiving the rehabilitation therapy in the clinical application.

Rapid determination of hippuric acid as an exposure biomarker of toluene using a colorimetric assay and comparison with high-performance liquid chromatography.

Occupational exposure to toluene is associated with health risks that require reliable monitoring methods. Hippuric acid (HA), a urinary metabolite of toluene, serves as a valuable biomarker for such exposure. Colorimetric methods for the quantitative determination of HA have gained prominence due to their simplicity, cost-effectiveness, and suitability for field application. In the present study, a simple colorimetric technique was optimized for the determination of HA in the urine sample, and compared with a usual HPLC technique. The central composite design (CCD) was applied to examine the effective parameters on the colorimetric determination of HA. The calibration curve for HA was established within the concentration range of 6 to 100 mg L-1 with R2 = 0.97. The detection limit (LOD) and quantification limit (LOQ) were determined to be 1.8 mg L-1 and 6 mg L-1 respectively. The relative standard deviation (RSD%) was less than 5%, and the recovery% (R%) was 90.5-100.1. The overall results showed good agreement between the colorimetric and HPLC results. There was a significant relationship between the results obtained from HPLC and colorimetric methods especially for higher concentration levels of HA (≥ 500 mg/g creatinine). In conclusion, our optimized colorimetric method is a simple, cost-effective, and rapid method for determination of HA in occupational exposure, which is comparable with the HPLC technique.

Daily Inhaled Corticosteroids Treatment Abolishes Airway Hyperresponsiveness to Mannitol in Defence and Police Recruits.

Background: Airway hyperresponsiveness (AHR) is a key pathophysiological feature of asthma and causes exercise-induced bronchoconstriction (EIB). Indirect bronchial provocation tests (BPTs) (e.g., exercise, mannitol) aid to diagnose asthma and identify EIB. Daily inhaled corticosteroids (ICS) can abolish AHR caused by indirect stimuli. Where strenuous physical exertion is integral to an occupation, identification of those at risk of EIB is important and documentation of inhibition of AHR with ICS is required before recruitment. Methods/Objectives: A retrospective analysis was performed on 155 potential recruits with AHR to mannitol who underwent follow-up assessment after daily ICS treatment to determine the proportion that can abolish AHR using ICS and to determine any predictors of the persistence of AHR. Results: Airway hyperresponsiveness was abolished in the majority (84%, n = 130) over the treatment period (mean ± SD 143 ± 72days), and it was defined as the provoking dose of mannitol to cause a 15% fall in FEV1 (cumulative inhaled dose of mannitol to cause 15% fall in FEV1, PD15) improved from (GeoMean) 183 to 521 mg. Compared with recruits in whom AHR was abolished with daily ICS (i.e., no 15% fall in FEV1 to the maximum cumulative dose of mannitol of 635 mg), in those where AHR remained (16%, n = 25), baseline AHR was more severe (PD15: 85 mg vs. 213 mg, P < 0.001), baseline FEV1% was lower (89 vs. 96%; 95%CI:2-12, P=0.004), and they had a longer follow-up duration (180 vs. 136 days; 13-74, P = 0.006). Baseline FEV1% (adjusted odds ratio 0.85; 95%CI:0.77-0.93), FEV1/FVC (0.78; 0.67-0.90), FEF25-75% (1.15; 1.06-1.25), and airway reactivity to mannitol (%Fall/cumulative dose of mannitol multiplied by 100) (1.07; 1.03-1.11) predicted AHR remaining after daily ICS. Conclusion: Airway hyperresponsiveness to mannitol can be abolished after 20 weeks of daily treatment with ICS. Inhibition of AHR is likely due to attenuation of airway inflammation in response to ICS treatment. Increased airway reactivity and lower spirometry variables predicted the persistence of AHR. Thus, those with a slower response to daily ICS on AHR can potentially be identified at the commencement of monitoring ICS using inhaled mannitol.

Impressions on the current state of cognitive neuroscience in occupational measurement.

Cognitive neuroscience is currently finding itself as a marketing trend in occupational science, particularly in terms of workplace assessment and measurement. However, the field has historically had little to do with occupational applications and has generally remained focused on the clinical and academic relevance of its research. We will explore several frontiers where research methods and theory established in cognitive neuroscience are beginning to produce meaningful applications in the workplace. Given that this application is likely to be unfamiliar with many in brain research, we look to outline concepts that should be perceived as key considerations when applying innovative measures to the workplace. Relating to these key considerations are several challenges that currently stand in the way of cognitive neuroscience progressing beyond a marketing trend into a steadfast perspective in occupational science.

Allen Cognitive Level Screen for the classification of subjects treated for addiction.

Introduction The Cognitive Disabilities Model (CDM) is an occupational approach that can allow the classification of the functional-cognitive abilities of persons with addictions. The objective of the study was to explore the applicability of the ACLS-5 to assess a sample of persons undergoing addiction-rehabilitation treatment. Methods A sample of 232 participants was recruited from an outpatient treatment centre in Madrid (Spain). The ACLS-5, the Montreal Cognitive Assessment (MoCA), and the Prefrontal Symptom Inventory (PSI) were administered. Sociodemographic and addiction-related data were also obtained. Results Half of the sample showed serious deficits in functional cognition, which ultimately could be related to problems in their daily performance. Scores of ACLS-5 showed significant correlations with the severity of addiction, with those obtained with the MoCA, and with attentional symptoms on the PSI scale. Conclusions The data suggest the applicability of the ACLS-5 in assessing the degree of functional cognition in subjects treated for addiction, providing evidence to support ecological validity and facilitating the development of well-targeted cognitive rehabilitation programmes from an occupational perspective. The use of occupational-based instruments to assess the functioning of those with addictions is a requirement of occupational therapy professionals working in this general area.

Dynamic occupation assessment of executive function in adolescents with schizophrenia spectrum disorders: An initial report.

OBJECTIVE: This study presents an initial evaluation of the psychometric properties of the Dynamic Occupation Assessment of Executive Function (DOAEF), a new tool designed to assess adolescents' executive function (EF) in daily situations and offering two levels of mediation through the administration process. METHOD: In the preliminary study, we tested 22 healthy adolescents. In the advanced stage, the instrument was administered to 105 healthy adolescents and to another 92 adolescents diagnosed with schizophrenia spectrum disorders. Information regarding EF was assessed by the DOAEF and Wisconsin Card Sorting Computer Version Test (WCST-CV-64). RESULTS: Inter-rater, test-retest and internal consistency indices were found to be satisfactory. Correlation between the DOAEF and the WCST-CV-64 scores supports the DOAEF's convergent validity. Significant differences were found between the healthy participants and the adolescents diagnosed with schizophrenia spectrum disorders, thus supporting the DOAEF's criterion validity. CONCLUSION: The DOAEF may be useful in assessing the level of mediation, which patients need for the comprehension of daily situations in which EFs are required.

Reliability and validity of lumbar and abdominal trunk muscle endurance tests in office workers with nonspecific subacute low back pain.

BACKGROUND AND OBJECTIVE: Despite the widespread use of trunk endurance tests, the reliability and validity of these tests in office workers with subacute nonspecific low back pain are unknown. MATERIALS AND METHODS: This cross-sectional study involved 190 subjects: 30 men and 42 women without low back pain and 47 men and 71 women with low back pain. All subjects underwent timed prone and supine isometric lumbar and abdominal trunk endurance tests that were performed until subjective fatigue occurred. All subjects also completed the Roland Morris and Oswestry self-reported disability questionnaires. A test-retest study (7 days) was conducted with 31 participants with low back pain from the study. RESULTS: For the abdominal trunk endurance test, males and females with low back pain had mean (SD) values of 62.06 (36.87) and 46.06 (29.28) seconds, respectively, both significantly lower than the asymptomatic workers. For the lumbar test, males and females with low back pain had mean (SD) values of 79.57 (30.66) and 75.49 (28.97) seconds, respectively, again, both significantly lower than the asymptomatic workers. The intraclass correlation coefficients of both tests exceeded 0.90 and the Kappa indices were excellent for both men and women. Receiver-operating curve analyses revealed areas under the curve very close to or exceeding 0.70 for both men and women for both tests. CONCLUSIONS: The lumbar and abdominal trunk muscle endurance tests appeared to be reliable and valid measures in office workers with subacute low back pain.

Valoración ocupacional de las personas con discapacidad, desde la perspectiva de las capacidades humanas / An occupational evaluation of disabled people from a humanabilities' viewpoint

RESUMEN Objetivo Describir el proceso de construcción de la herramienta denominada Valoración Ocupacional de las personas con discapacidad en Colombia. Método Estudiomultimétodos, constituido por cinco fases, acompañadas por una estrategia transversal acompañada de diversos actores. La primera fase se basó en revisión documental, la segunda en juicio de expertos, La tercera permitió la evaluación de la herramienta por pares. La cuarta fase consistió en una prueba piloto, y la quinta fase se dedicó a la socialización de las herramientas con los actores participantes, para conocer sus sugerencias para el ajuste final. Resultados Se construyó una herramienta para valorar ocupacionalmente a personas con discapacidad en Colombia, basada en el enfoque de las capacidades humanas y el funcionamiento y de competencias laborales generales para favorecer la inclusión laboral. Conclusiones Se cuenta con una herramienta que promueva la inclusión laborar de las personas con discapacidad, respondiendo a lo contemplado en la Ley 1346 de 2009, Ley 1618 de 2013 y lo planteado en la Convención Internacional de los Derechos de las Personas con discapacidad. No reemplaza a las herramientas existentes, pero si promueve una percepción más favorable de las personas con discapacidad, facilitando su inclusión laboral.

ABSTRACT Objective Describing how a tool was designed for assessing disabled people in Colombia (called "Occupational evaluation of handicapped people in Colombia"). Method This was a multi-method studywhich consisted of five phases and a stakeholder participation-based strategy. The first stage of the multi-method research involved a literature review followed by expert judgment and then peer assessment of the tool; the fourth stage involved a pilot study and and a basic training course in occupational assessment involved the tool's socialisation with actors working in the field of occupational assessment, taking their suggestions into account for final adjustment of the tool. Results A tool was developed for the occupational assessment of disabled people in Colombia which was based on identifying their capabilities in terms of performance and general work skills to promote their inclusion in the workforce. Conclusions Considering the Colombian state's responsibility for ensuring disabled people's right to work and their inclusion in the workforce (Law 1346/2009, Law 1618/2013 and Convention on the Rights of People with Disabilities (CRPD)), this tool will not replace existing ones but will promote a more favourable perception of disabled people, thereby facilitating their inclusion in the workforce.