Assessment of Area Radiation Dose for the National Cyclotron and PET Centre at Chulabhorn Hospital in Thailand.

The National Cyclotron and PET Centre at Chulabhorn Hospital offers nuclear medicine diagnostic services using state-of-the-art digital PET/CT and PET/MRI machines as well as other related devices. Additionally, the center plays a vital role by having a cyclotron to produce radiopharmaceuticals, which are used both in-house and in other hospitals throughout the country. Despite the center's strict adherence to international standards regarding the use of radioactive substances in patients, there remains a potential risk of radiation exposure for operators, workers, and the public due to radioactive contamination and emissions from unsealed sources. Hence, it is imperative to assess and continuously monitor radiation levels in the work area to ensure the utmost level of safety for personnel. Methods: This study used optically stimulated luminescence dosimeters to measure radiation levels in 17 areas, consisting of 9 controlled and 8 supervised areas. Over a 3-mo period, the average monthly radiation dose was recorded for each location. Results: The PET/CT room registered the highest radiation dose within the controlled area, with a monthly average of 1.81 ± 0.29 mSv, equivalent to an annual dose of 21.72 mSv. This higher dose can be attributed to the significant number of patients served in this room. In supervised areas, the nursing counter located between the examination room and the patient waiting area exhibited the highest radiation exposure. The average monthly dose measured at this location was 0.085 ± 0.019 mSv, resulting in an annual dose of 1.015 mSv. Conclusion: The evaluation of radiation dose in controlled and supervised areas indicated that the overall radiation level remains within the prescribed limits. However, the slight excess that was observed at the nursing counter indicates the need for improvement to ensure compliance with the as-low-as-reasonably-achievable principle. Continuous monitoring of radiation levels should be conducted annually to maintain safety standards and minimize the risk that workers and the general public will be exposed to radioactivity.

Association between exposure to metalworking fluid aerosols, occupational noise and chronic kidney disease: a cross-sectional study in China.

BACKGROUND: Chronic kidney disease (CKD) carries a high public health burden yet little is known about the relationship between metalworking fluid (MWF) aerosols, occupational noise and CKD. We aimed to explore the relationship between occupational MWF aerosols, occupational noise and CKD. METHODS: A total of 2,738 machinists were sampled from three machining companies in Wuxi, China, in 2022. We used the National Institute for Occupational Safety and Health (NIOSH) method 5524 to collect individual samples for MWF aerosols exposure, and the Chinese national standard (GBZ/T 189.8-2007) method to test individual occupational noise exposure. The diagnostic criteria for CKD were urinary albumin/creatinine ratio (UACR) of ≥ 30 mg/g and reduced renal function (eGFR < 60 mL.min- 1. 1.73 m- 2) lasting longer than 3 months. Smooth curve fitting was conducted to analyze the associations of MWF aerosols and occupational noise with CKD. A segmented regression model was used to analyze the threshold effects. RESULTS: Workers exposed to MWF aerosols (odds ratio [OR] = 2.03, 95% confidence interval [CI]: 1.21-3.41) and occupational noise (OR = 1.77, 95%CI: 1.06-2.96) had higher prevalence of CKD than nonexposed workers. A nonlinear and positive association was found between increasing MWF aerosols and occupational noise dose and the risk of CKD. When daily cumulative exposure dose of MWF aerosols exceeded 8.03 mg/m3, the OR was 1.24 (95%CI: 1.03-1.58), and when occupational noise exceeded 87.22 dB(A), the OR was 1.16 (95%CI: 1.04-1.20). In the interactive analysis between MWF aerosols and occupational noise, the workers exposed to both MWF aerosols (cumulative exposure ≥ 8.03 mg/m3-day) and occupational noise (LEX,8 h ≥ 87.22 dB(A)) had an increased prevalence of CKD (OR = 2.71, 95%CI: 1.48-4.96). MWF aerosols and occupational noise had a positive interaction in prevalence of CKD. CONCLUSIONS: Occupational MWF aerosols and noise were positively and nonlinearly associated with CKD, and cumulative MWF aerosols and noise exposure showed a positive interaction with CKD. These findings emphasize the importance of assessing kidney function of workers exposed to MWF aerosols and occupational noise. Prospective and longitudinal cohort studies are necessary to elucidate the causality of these associations.

Higher exposure to 1,3-butadiene is associated with more severe hearing loss.

While volatile organic compounds (VOCs) impair various organs, their influence on hearing loss (HL) has not been extensively researched. We aimed to identify the association between VOCs and HL or high-frequency hearing loss (HFHL). We extracted data on age, sex, pure tone audiometry, hypertension, occupational noise exposure, and creatinine-corrected urine VOC metabolite concentrations from the eighth Korea National Health and Nutrition Survey. Among the VOC metabolites, N-acetyl-S-(benzyl)-L-cysteine (BMA, P = 0.004), N-acetyl-S-(phenyl)-L-cysteine (SPMA, P = 0.027), and N-acetyl-S-(3,4-dihydroxybutyl)-L-cysteine (DHBMA, P < 0.001) showed associations with HL. Additionally, HFHL exhibited significant associations with BMA (P = 0.005), 3- and 4-methylhippuric acid (3, 4 MHA, P = 0.049), mandelic acid (MA, P = 0.015), SPMA (P < 0.001), N-acetyl-S-(3-hydroxypropyl)-L-cysteine (3-HPMA, P < 0.001), and DHBMA (P < 0.001). After controlling other factors, DHBMA were associated with HL (P = 0.021) and HFHL (P = 0.014) and exhibited a linear association with the mean hearing level (ß = 0.054, P = 0.024) and high-frequency hearing level (ß = 0.045, P = 0.037). Since 1,3-butadiene may act as an ototoxic material, early screening for workers exposed to 1,3-butadiene and reducing exposure to 1,3-butadiene in everyday life may be helpful to prevent further HL.

Physical function as a marker to assess the effects of occupational long-term pesticide exposure.

In this cross-sectional study, we determined the relative impact of long-term occupational exposure to pesticides on physical performance and perception of tiredness. Experimental data was collected in locus from agricultural communities and included surveys to assess the duration of exposure to pesticides, social status, habitual physical activity levels, presence of common mental disorders (CMD), and self-reported tiredness. Plasmatic cholinesterase (PChE), body composition and traditional functional performance tests (Handgrip strength-HGS; Time up and go-TUG; and Sit-to-stand-STS) were obtained. From the 127 individuals tested, cluster analysis yielded 80 individuals divided in Direct Exposed (n = 37) and Indirect Exposed (n = 43); Tired (n = 16), and Not Tired (n = 64). PChE values were within the reference values (5209.64-13943.53 U/L). Pesticide exposure had no influence on PChE levels, CMD or fatigue (p > 0.05), while Self-reported tiredness had (p < 0.05). Principal Component Analyses showed that HGS; STS and TUG (i.e., physical performance variables) are negatively influenced by two independent factors: pesticide exposure and self-reported tiredness. We conclude that chronic pesticide exposure and tiredness can negatively impact physical performance, independently, without clinically significant changes in PChE levels that is a biomarker used to track pesticide intoxication. Functional physical tests can be a useful tool to identify chronic pesticide exposure, and help with the limitations of commonly used parameters (i.e. PChE and CMD). Self-reported tiredness is a confounding variable.

Impact of air quality on the health of present-day workers in an Asbestos roof manufacturing industry, Sri Lanka.

The study's objective was to determine the air quality in an asbestos-related industry and its impact on current workers' respiratory health. Seventy-seven air and 65 dust samples were collected at 5-day intervals in an asbestos roofing sheets production factory in Sri Lanka having two production facilities. Sampling was performed in ten sites: Defective sheets-storage, Production-plant, Pulverizer, Cement-silo, and Loading-area. A detailed questionnaire and medical screening were conducted on 264 workers, including Lung Function Tests (LFT) and chest X-rays. Asbestos fibres were observed in deposited dust samples collected from seven sites. Free chrysotile fibres were absent in the breathing air samples. Scanning Electron Microscopy confirmed the presence of asbestos fibres, and the Energy Dispersive X-ray analysis revealed Mg, O, and Si in depositions. The average concentrations of trace metals were Cd-2.74, Pb-17.18, Ni-46.68, Cr-81.01, As-7.12, Co-6.77, and Cu-43.04 mg/kg. The average Zn, Al, Mg, and Fe concentrations were within 0.2-163 g/kg. The highest concentrations of PM2.52.5 and PM1010, 258 and 387 µg/m3, respectively, were observed in the Pulverizer site. Forty-four workers had respiratory symptoms, 64 presented LFT abnormalities, 5 indicated chest irregularities, 35.98% were smokers, and 37.5% of workers with abnormal LFT results were smokers. The correlation coefficients between LFT results and work duration with respiratory symptoms and work duration and chest X-ray results were 0.022 and 0.011, respectively. In conclusion, most pulmonary disorders observed cannot directly correlate to Asbestos exposure due to negligible fibres in breathing air, but fibres in the depositions and dust can influence the pulmonary health of the employees.

Relationship between assistant's lens exposure and dose information during computed tomography examinations.

According to International Commission of Radiological Protection, the equivalent dose limit for the eye lens for occupational exposure is recommended to be 20 mSv yr-1, averaged over 5 years, with no single year above 50 mSv. Some studies reported the measurement of assistant's lens exposure in diagnostic computed tomography (CT) examinations, but further investigation is still required in the association between the lens dose for assistants and various dose parameters. Therefore, we measured the assistant's lens exposure using small optically stimulated luminescence dosimeters. The type of occupation, type of assistance, total scan time, total mAs, total scan length, and dose-length product (DLP) were recorded and analyzed in association with air kerma at the lens position. The assistance was classified into four types: 'assisted ventilation,' 'head holding,' 'body holding,' and 'raising patient's arm.' The air kerma of lens position was not significantly different for each assistance type (p< 0.05, Kruskal-Wallis test). Further, the lens doses for assistants correlated with DLP, but with various strengths of correlation with the assistance type and were influenced by the distance from the CT gantry. In conclusion, lens dose during assistance and DLP demonstrated the strongest correlation. 'Raising patient's arm' and 'head holding' exhibited stronger correlations, which required less table movement during the CT scan than 'assisted ventilation' and 'body holding'.

Asbestos exposures associated with the use and handling of drilling mud additives.

This paper summarizes historical asbestos exposure data collected during the handling of short-fiber chrysotile asbestos that was used as an additive to drilling fluid in oil and gas exploration. A total of 1171 industrial hygiene (IH) personal and area air samples were collected and analyzed from more than 20 drilling rigs between 1972 and 1985. The dataset consists of 1097 short-term samples (<240 min) with more than 80% having sample durations less than 30 min. Average airborne fiber concentrations measured during asbestos handling activities ranged from 0.62 f/cc to 3.39 f/cc using phase-contrast microscopy (PCM). An additional 14 samples were considered long-term samples (>240 min) and there were 60 samples with no reported sample duration. Eight-hour time-weighted average (8-h TWA) results, calculated using short-term samples, along with long-term samples greater than 240 min, did not exceed contemporaneous Occupational Safety and Health Administration (OSHA) permissible exposure limits (PELs). This analysis fills a data gap in the evaluation of asbestos exposures from the use of drilling mud additives (DMAs) that contained chrysotile asbestos.

The relative contribution of PM2.5 components to the obstructive ventilatory dysfunction-insights from a large ventilatory function examination of 305,022 workers in southern China.

BACKGROUND: The new round of WHO/ILO Joint Estimates of the Work-related Burden of Disease assessment requires futher research to provide more evidence, especially on the health impact of ambient air pollution around the workplace. However, the evidence linking obstructive ventilatory dysfunction (OVD) to fine particulate matter (PM2.5) and its chemical components in workers is very limited. Evidence is even more scarce on the interactive effects between occupational factors and particle exposures. We aimed to fill these gaps based on a large ventilatory function examination of workers in southern China. METHODS: We conducted a cross-sectional study among 363,788 workers in southern China in 2020. The annual average concentration of PM2.5 and its components were evaluated around the workplace through validated spatiotemporal models. We used mixed-effect models to evaluate the risk of OVD related to PM2.5 and its components. Results were further stratified by basic characteristics and occupational factors. FINDINGS: Among the 305,022 workers, 119,936 were observed with OVD. We found for each interquartile range (IQR) increase in PM2.5 concentration, the risk of OVD increased by 27.8 (95 % confidence interval (CI): 26.5-29.2 %). The estimates were 10.9 % (95 %CI: 9.7-12.1 %), 15.8 % (95 %CI: 14.5-17.2 %), 2.6 % (95 %CI: 1.4-3.8 %), 17.1 % (95 %CI: 15.9-18.4 %), and 11 % (95 %CI: 9.9-12.2 %), respectively, for each IQR increment in sulfate, nitrate, ammonium salt, organic matter and black carbon. We observed greater effect estimates among females, younger workers, workers with a length of service of 24-45 months, and professional skill workers. Furthermore, it is particularly noteworthy that the noise-exposed workers, high-temperature-exposed workers, and less-dust-exposed workers were at a 5.7-68.2 % greater risk than others. INTERPRETATION: PM2.5 and its components were significantly associated with an increased risk of OVD, with stronger links among certain vulnerable subgroups.

Characterization of fire investigators' polyaromatic hydrocarbon exposures using silicone wristbands.

BACKGROUND: Exposures to polyaromatic hydrocarbons (PAHs) contribute to cancer in the fire service. Fire investigators are involved in evaluations of post-fire scenes. In the US, it is estimated that there are up to 9000 fire investigators, compared to approximately 1.1 million total firefighting personnel. This exploratory study contributes initial evidence of PAH exposures sustained by this understudied group using worn silicone passive samplers. OBJECTIVES: Evaluate PAH exposures sustained by fire investigators at post-fire scenes using worn silicone passive samplers. Assess explanatory factors and health risks of PAH exposure at post-fire scenes. METHODS: As part of a cross-sectional study design, silicone wristbands were distributed to 16 North Carolina fire investigators, including eight public, seven private, and one public and private. Wristbands were worn during 46 post-fire scene investigations. Fire investigators completed pre- and post-surveys providing sociodemographic, occupational, and post-fire scene characteristics. Solvent extracts from wristbands were analyzed via gas chromatography-mass spectrometry (GC-MS). Results were used to estimate vapor-phase PAH concentration in the air at post-fire scenes. RESULTS: Fire investigations lasted an average of 148 minutes, standard deviation ± 93 minutes. A significant positive correlation (r=0.455, p<.001) was found between investigation duration and PAH concentrations on wristbands. Significantly greater time-normalized PAH exposures (p=0.039) were observed for investigations of newer post-fire scenes compared to older post-fire scenes. Regulatory airborne PAH exposure limits were exceeded in six investigations, based on exposure to estimated vapor-phase PAH concentrations in the air at post-fire scenes. DISCUSSION: Higher levels of off-gassing and suspended particulates at younger post-fire scenes may explain greater PAH exposure. Weaker correlations are found between wristband PAH concentration and investigation duration at older post-fire scenes, suggesting reduction of off-gassing PAHs over time. Exceedances of regulatory PAH limits indicate a need for protection against vapor-phase contaminants, especially at more recent post-fire scenes.

Leukemia risk assessment of exposure to low-levels of benzene based on the linearized multistage model.

Objectives: To assess leukemia risk in occupational populations exposed to low levels of benzene. Methods: Leukemia incidence data from the Chinese Benzene Cohort Study were fitted using the Linearized multistage (LMS) model. Individual benzene exposure levels, urinary S-phenylmercapturic acid (S-PMA) and trans, trans-muconic acid (t, t-MA) were measured among 98 benzene-exposed workers from factories in China. Subjects were categorized into four groups by rounding the quartiles of cumulative benzene concentrations (< 3, 3-5, 5-12, ≥12 mg/m3·year, respectively). The risk of benzene-induced leukemia was assessed using the LMS model, and the results were validated using the EPA model and the Singapore semi-quantitative risk assessment model. Results: The leukemia risks showed a positive correlation with increasing cumulative concentration in the four exposure groups (excess leukemia risks were 4.34, 4.37, 4.44 and 5.52 × 10-4, respectively; Ptrend < 0.0001) indicated by the LMS model. We also found that the estimated leukemia risk using urinary t, t-MA in the LMS model was more similar to those estimated by airborne benzene compared to S-PMA. The leukemia risk estimated by the LMS model was consistent with both the Singapore semi-quantitative risk assessment model at all concentrations and the EPA model at high concentrations (5-12, ≥12 mg/m3·year), while exceeding the EPA model at low concentrations (< 3 and 3-5 mg/m3·year). However, in all four benzene-exposed groups, the leukemia risks estimated by these three models exceeded the lowest acceptable limit for carcinogenic risk set by the EPA at 1 × 10-6. Conclusion: This study demonstrates the utility of the LMS model derived from the Chinese benzene cohort in assessing leukemia risk associated with low-level benzene exposure, and suggests that leukemia risk may occur at cumulative concentrations below 3 mg/m3·year.

Personal protective equipment for preventing asbestos exposure in workers.

BACKGROUND: Asbestos exposure can lead to asbestos-related diseases. The European Union (EU) has adopted regulations for workplaces where asbestos is present. The EU occupational exposure limit (OEL) for asbestos is 0.1 fibres per cubic centimetre of air (f/cm3) as an eight-hour average. Different types of personal protective equipment (PPE) are available to provide protection and minimise exposure; however, their effectiveness is unclear. OBJECTIVES: To assess the effects of personal protective equipment (PPE), including donning and doffing procedures and individual hygienic behaviour, compared to no availability and use of such equipment or alternative equipment, on asbestos exposure in workers in asbestos demolition and repair work. SEARCH METHODS: We searched MEDLINE, Embase, CENTRAL, and Scopus (September 2022), and we checked the reference lists of included studies. SELECTION CRITERIA: We included studies that measured asbestos concentration outside and inside PPE (considering outside concentration a surrogate for no PPE), exposure to asbestos after doffing PPE, donning and doffing errors, nonadherence to regulations, and adverse effects of PPE. DATA COLLECTION AND ANALYSIS: Two review authors selected studies, extracted data, and assessed risk of bias using ROBINS-I. We categorised PPE as full-face filtering masks, supplied air respirators (SARs), and powered air-purifying respirators (PAPRs). Values for asbestos outside and inside PPE were transformed to logarithmic values for random-effects meta-analysis. Pooled logarithmic mean differences (MDs) were exponentiated to obtain the ratio of means (RoM) and 95% confidence interval (95% CI). The RoM shows the degree of protection provided by the respirators (workplace protection factor). Since the RoM is likely to be much higher at higher outside concentrations, we presented separate results according to the outside asbestos concentration, as follows. • Below 0.01 f/cm3 (band 1) • 0.01 f/cm3 to below 0.1 f/cm3 (band 2) • 0.1 f/cm3 to below 1 f/cm3 (band 3) • 1 f/cm3 to below 10 f/cm3 (band 4) • 10 f/cm3 to below 100 f/cm3 (band 5) • 100 f/cm3 to below 1000 f/cm3 (band 6) Additionally, we determined whether the inside concentrations per respirator and concentration band complied with the current EU OEL (0.1 f/cm3) and proposed EU OEL (0.01 f/cm3). MAIN RESULTS: We identified six studies that measured asbestos concentrations outside and inside respiratory protective equipment (RPE) and one cross-over study that compared the effect of two different coveralls on body temperature. No studies evaluated the remaining predefined outcomes. Most studies were at overall moderate risk of bias due to insufficient reporting. The cross-over study was at high risk of bias. Full-face filtering masks Two studies evaluated full-face filtering masks. They provided insufficient data for band 1 and band 6. The results for the remaining bands were as follows. • Band 2: RoM 19 (95% CI 17.6 to 20.1; 1 study, 3 measurements; moderate certainty) • Band 3: RoM 69 (95% CI 26.6 to 175.9; 2 studies, 17 measurements; very low certainty) • Band 4: RoM 455 (95% CI 270.4 to 765.1; 1 study, 16 measurements; low certainty) • Band 5: RoM 2752 (95% CI 1236.5 to 6063.2;1 study, 3 measurements; low certainty) The inside measurements in band 5 did not comply with the EU OEL of 0.1 f/cm3, and no inside measurements complied with the proposed EU OEL of 0.01 f/cm3. Supplied air respirators Two studies evaluated supplied air respirators. They provided no data for band 6. The results for the remaining bands were as follows. • Band 1: RoM 11 (95% CI 7.6 to 14.9; 1 study, 134 measurements; moderate certainty) • Band 2: RoM 63 (95% CI 43.8 to 90.9; 1 study, 17 measurements; moderate certainty) • Band 3: RoM 528 (95% CI 368.7 to 757.5; 1 study, 38 measurements; moderate certainty) • Band 4: RoM 4638 (95% CI 3071.7 to 7044.5; 1 study, 49 measurements; moderate certainty) • Band 5: RoM 26,134 (16,647.2 to 41,357.1; 1 study, 22 measurements; moderate certainty) All inside measurements complied with the current OEL of 0.1 f/cm3 and the proposed OEL of 0.01 f/cm3. Powered air-purifying respirators Three studies evaluated PAPRs. The results per band were as follows. • Band 1: RoM 8 (95% CI 3.7 to 19.1; 1 study, 23 measurements; moderate certainty) • Band 2: RoM 90 (95% CI 64.7 to 126.5; 1 study, 17 measurements; moderate certainty) • Band 3: RoM 104 (95% CI 23.1 to 464.1; 3 studies, 14 measurements; very low certainty) • Band 4: RoM 706 (95% CI 219.2 to 2253.0; 2 studies, 43 measurements; very low certainty) • Band 5: RoM 1366 (544.6 to 3428.9; 2 studies, 8 measurements; low certainty) • Band 6: RoM 18,958 (95% CI 4023.9 to 90,219.4; 2 studies, 13 measurements; very low certainty) All inside measurements complied with the 0.1 f/cm3 OEL when the outside concentration was below 10 f/cm3 (band 1 to band 4). From band 3, no measurements complied with the proposed OEL of 0.01 f/cm3. Different types of coveralls One study reported the adverse effects of coveralls. A polyethylene suit may increase the body temperature more than a ventilated impermeable polyvinyl (PVC) coverall, but the evidence is very uncertain (MD 0.17 °C, 95% CI -0.08 to 0.42; 1 study, 11 participants; very low certainty). AUTHORS' CONCLUSIONS: Where the outside asbestos concentration is below 0.1 f/cm3, SARS and PAPRs likely reduce exposure to below the proposed OEL of 0.01 f/cm3. For outside concentrations up to 10 f/cm3, all respirators may reduce exposure below the current OEL, but only SAR also below the proposed OEL. In band 5 (10 to < 100 f/cm3), full-face filtering masks may not reduce asbestos exposure below either OEL, SARs likely reduce exposure below both OELs, and there were no data for PAPRs. In band 6 (100 f/cm3 to < 1000 f/cm3), PAPRs may not reduce exposure below either OEL, and there were no data for full-face filtering masks or SARs. Some coveralls may increase body temperature more than others. Randomised studies are needed to directly compare PAPRs and SARs at higher asbestos concentrations and to assess adverse effects. Future studies should assess the effects of doffing procedures.

Surveillance of Occupational Exposure to Volatile Organic Compounds at Gas Stations: A Scoping Review Protocol.

Health surveillance guides public policies, allows for the monitoring of occupational exposures that may cause health risks, and can prevent work-related diseases. The scoping review protocol herein is designed to map studies on the surveillance of occupational exposure to volatile organic compounds (VOCs) in gas stations and identify the governmental agencies and public health measures in different countries. This review protocol is based on the Joanna Briggs Institute manual and guided by the PRISMA Extension for Scoping Reviews. It includes research articles, theses, dissertations, and official documents on surveillance measures for occupational exposure to VOCs (i.e., benzene, ethylbenzene, toluene, and xylene) in gas stations from different countries. All languages and publication dates will be considered, and a spreadsheet will be used to extract and analyze qualitative and quantitative data. The final version will present the main surveillance measures implemented, responsible entities, results, challenges, limitations, and potential gaps in gas stations.

Thermoluminescence dosimetry (TLD) in a 3 T magnetic resonance imaging (MRI) environment: implications for personnel exposure monitoring.

Thermoluminescent dosimeters (TLDs) serve as compact and user-friendly tools for various applications, including personal radiation dosimetry and radiation therapy. This study explores the potential of utilizing TLD-100 personal dosimetry, conventionally applied in PET/CT (positron emission tomography/computed tomography) settings, in the PET/MRI (magnetic resonance imaging) environment. The integration of MRI into conventional radiotherapy and PET systems necessitates ionizing radiation dosimetry in the presence of static magnetic fields. In this study, TLD-100 dosimeters were exposed on the surface of a water-filled cylindrical phantom containing PET-radioisotope and positioned on the patient table of a 3 T PET/MRI, where the magnetic field strength is around 0.2 T, aiming to replicate real-world scenarios experienced by personnel in PET/MRI environments. Results indicate that the modified MR-safe TLD-100 personal dosimeters exhibit no significant impact from the static magnetic field of the 3 T PET/MRI, supporting their suitability for personal dosimetry in PET/MRI settings. This study addresses a notable gap in existing literature on the effect of MRI static magnetic field on TLDs.

Parameter uncertainty analysis of the equivalent lung dose coefficient for the intake of radon in mines: A review.

Radon presents significant health risks due to its short-lived progeny. The evaluation of the equivalent lung dose coefficient is crucial for assessing the potential health effects of radon exposure. This review focuses on the uncertainty analysis of the parameters associated with the calculation of the equivalent lung dose coefficient attributed to radon inhalation in mines. This analysis is complex due to various factors, such as geological conditions, ventilation rates, and occupational practices. The literature review systematically examines the sources of radon and its health effects among underground miners. It also discusses the human respiratory tract model used to calculate the equivalent lung dose coefficient and the associated parameters leading to uncertainties in the calculated lung dose. Additionally, the review covers the different methodologies employed for uncertainty quantification and their implications on dose assessment. The text discusses challenges and limitations in current research practices and provides recommendations for future studies. Accurate risk assessment and effective safety measures in mining environments require understanding and mitigating parameter uncertainties.

Slovakian glass fibre factory genotoxicity biomonitoring study - unsupported adverse outcome pathway (AOP) from the toxicology and human epidemiological experience of synthetic vitreous fibres (SVFs).

The article by Ceppi and colleagues, Genotoxic Effects of Occupational Exposure to, Glass Fibres - A Human Biomonitoring Study, published in Mutation Research -Genetic Toxicology and Environmental Mutagenesis in 2023 was reviewed with great interest. The authors undertook a novel approach to conducting a biomonitoring study of genotoxicity markers among a population of glass fibre manufacturing workers in Slovakia. On the surface, the Ceppi et al. (2023) study provides an interesting application of genotoxicity markers among a human population of workers to explore potential markers of effect (DNA strand breaks) and potential risk of susceptibility (e.g., genetic damage, disease, death). However, limited data for exposure reconstruction, uncertain influences from smoking history, and lack of consideration of decades of human epidemiology research showing no increased risk of malignant or non-malignant respiratory disease and mortality among glass fibre manufacturing workers, reveals that the conclusions of the authors are overreaching and inconsistent with the existing science. The limitations of this study preclude the ability to draw causal inferences or conclusions about DNA strand breaks as a marker of exposure, effect, or susceptibility within this population of Slovakian glass fibre workers. Further longitudinal research is required (e.g., more robust temporal assessment of occupational exposures - fibres and other compounds - and smoking history) to support the study conclusions.

Radon Exposure Assessment in Occupational and Environmental Settings: An Overview of Instruments and Methods.

Radon is a naturally occurring noble radioactive gas that poses significant health risks, particularly lung cancer, due to its colorless, odorless, and tasteless nature, which makes detection challenging without formal testing. It is found in soil, rock, and water, and it infiltrates indoor environments, necessitating regulatory standards and guidelines from organizations such as the Environmental Protection Agency, the World Health Organization, and the Occupational Health and Safety Agency to mitigate exposure. In this paper, we present various methods and instruments for radon assessment in occupational and environmental settings. Discussion on long- and short-term monitoring, including grab sampling, radon dosimetry, and continuous real-time monitoring, is provided. The comparative analysis of detection techniques-active versus passive-is highlighted from real-time data and long-term exposure assessment, including advances in sensor technology, data processing, and public awareness, to improve radon exposure evaluation techniques.

Occupational exposure, carcinogenic and non-carcinogenic risk assessment of formaldehyde in the pathology labs of hospitals in Iran.

Formaldehyde, a known carcinogenic compound, is commonly used in various medical settings. The objective of this study was to assess the carcinogenic and non-carcinogenic risks associated with occupational exposure to formaldehyde. This study was conducted in the pathology labs of four hospitals in Tehran. Cancer and non-cancer risks were evaluated using the quantitative risk assessment method proposed by the United States environmental protection agency (USEPA), along with its provided database known as the integrated risk information system (IRIS). Respiratory symptoms were assessed using the American thoracic society (ATS) questionnaire. The results indicated that 91.23% of exposure levels in occupational groups exceed the NIOSH standard of 0.016 ppm. Regarding carcinogenic risk, 41.03% of all the studied subjects were in the definite carcinogenic risk range (LCR > 10-4), 23.08% were in the possible carcinogenic risk range (10-5 < LCR < 10-4), and 35.90% were in the negligible risk range (LCR < 10-6). The highest index of occupational carcinogenesis was observed in the group of lab technicians with a risk number of 3.7 × 10-4, followed by pathologists with a risk number of 1.7 × 10-4. Furthermore, 23.08% of the studied subjects were within the permitted health risk range (HQ < 1.0), while 76.92% were within the unhealthy risk range (HQ > 1.0). Overall, the findings revealed significantly higher carcinogenic and non-carcinogenic risks among lab technicians and pathologists. Therefore, it is imperative to implement control measures across various hospital departments to mitigate occupational formaldehyde exposure levels proactively. These findings can be valuable for policymakers in the health sector, aiding in the elimination or reduction of airborne formaldehyde exposure in work environments.

Medical staff dose estimation during pediatric cardiac interventional procedures.

The purpose of this study is to evaluate the occupational doses (eye lens, extremities and whole body) in paediatric cardiac interventional and diagnostic catheterization procedures performed in a paediatric reference hospital located in Recife, Pernambuco. For eye lens dosimetry, the results show that the left eye receives a higher dose than the right eye, and there is a small difference between the doses received during diagnostic (D) and therapeutic (T) procedures. The extrapolated annual values for the most exposed eye are close to the annual limit. For doses to the hands, it was observed that in a significant number of procedures (37 out of 45 therapeutic procedures, or 82%) at least one hand of the physician was exposed to the primary beam. During diagnostic procedures, the physician's hand was in the radiation field in 11 of the 17 catheterization procedures (65%). This resulted in a 10-fold increase in dose to the hands. The results underscore the need for optimization of radiation safety and continued efforts to engage staff in a radiation safety culture.

A study of inflammatory biomarkers in crystalline silica exposed rock drillers.

BACKGROUND: Crystalline silica (CS) exposure can cause serious lung disease in humans, but mechanisms of pulmonary toxicity have not been completely elucidated. AIMS: To assess pro-inflammatory and anti-inflammatory biomarkers and biomarkers related to the development of chronic obstructive pulmonary disease and fibrosis in serum of rock drillers exposed to CS. METHODS: Rock drillers (N = 123) exposed to CS and non-specified particulate matter (PM) were compared to 48 referents without current or past exposure to PM in a cross-sectional study. RESULTS: The rock drillers had been exposed to CS for 10.7 years on average. Geometric mean (GM) current exposure was estimated to 36 µg/m3. Their GM concentration of matrix metalloproteinase 12 (MMP-12) was significantly higher (16 vs. 13 ng/L; p = 0.04), while interleukin (IL) 6 and IL-8 were significantly lower compared to the referents. Also pentraxin 3 was significantly lower (3558 vs. 4592 ng/L; p = 0.01) in the rock drillers. A dose-response relationship was observed between cumulative exposure to CS and MMP-12, the highest exposed subgroup having significantly higher MMP-12 concentrations than the referents. CONCLUSION: Exposure to CS may increase circulating MMP-12 concentrations in a dose-response related fashion. The results may also suggest a down-regulation of pro-inflammatory pathways.

[Comparison of the application of new and old specification for occupational health surveillance of radiation workers and analysis of influencing factors].

Objective: To investigate the impact of the implementation of GBZ 98-2020 "Health Requirements and Surveillance Specifications for Radiation Worker" on the results of occupational health examination for radiation workers. Methods: In April 2022, the subjects of the study were the radiation workers who underwent occupational health examination in Occupational Disease Prevention and Treatment Institute of Hefei. The radiation workers whose registration period was from May 1, 2021 to April 30, 2022 were the new standard group, and the occupational health surveillance standard was GBZ 98-2020 "Health Requirements and Surveillance Specifications for Radiation Worker". The radiationl workers registered from May 1, 2020 to April 30, 2021 were the old standard group, whose occupational health surveillance standards were GBZ 98- 2017 "Health Requirements for Radiation Workers" and GBZ 235-2011 "Specifications for Occupational Health Surveillance for Radiation Workers". To analyze whether there were differences between the two groups in the detection rate of missing items in the examination, re-examination, and the detection rate of occupational contraindications. The radiation workers whose occupational health examination results showed re-examination and/or occupational contraindications were judged to be in the unqualified group. Univariate and multivariate logistic regression analysis was used to find the factors affecting the determination of unqualified group. Results: The missing item detection rate of radiation workers in the new standard group was 3.04% (63/2074) , significantly higher than that in the old standard group (0.68%, 14/2054) (P<0.05) . The re-examination and occupational contraindications detection rates in the new standard group were 5.93% (123/2074) and 0.58% (12/2074) , respectively, which were significantly lower than those in the old standard group (13.83%, 284/2054) and 2.34% (48/2054) (P<0.05) . The missing item detection rate of males in the new standard group was 2.78% (40/1440) , which was significantly higher than that in the old standard group (0.72%, 11/1536) (P<0.05) . The re-examination and occupational contraindications detection rates of males in the new standard group were 3.61% (52/1440) and 0.21% (3/1440) , respectively, which were significantly lower than those in the old standard group (12.17%, 187/1536) and 2.08% (32/1536) (P<0.05) . The missing item detection rate of females in the new standard group was 3.63% (23/634) , which was significantly higher than that in the old standard group (0.58%, 3/518) (P<0.05) . The re-examination detection rate of females in the new standard group was 11.20% (71/634) , which was significantly lower than that of females in the old standard group (18.73%, 97/518) (P<0.05) . Univariate logistic regression analysis showed that gender, radiation classification, determination basis, occupational health examination category, and registration category were all influencing factors for the unqualified occupational health examination results of radiation workers (P<0.05) . Multivariate logistic regression analysis showed that the risk of being judged as unqualified based on the old standard was 2.466 times that of the new standard (95%CI: 1.975-3.080, P<0.05) , and the risk of being judged as unqualified for females was 1.869 times that of males (95%CI: 1.498-2.333, P<0.05) , the risk of being judged as unqualified for radiation workers during and after employment was 0.802 times that of pre-employment individuals (95%CI: 0.650-0.989, P<0.05) , and the risk of being judged as unqualified for re-examined individuals was 4.056 times that of initial examinees (95%CI: 3.161-5.203, P<0.05) . Conclusion: The results of occupational health examination of radiation workers are related to the determination basis, gender, occupational health examination category, and registration category. The implementation of GBZ 98-2020 "Health Requirements and Surveillance Specifications for Radiation Worker" may reduce the detection rate of unqualified personnel.