Chronic exposure to work-related mental stressors has been linked to higher risk of disease, possibly mediated by effects on the normal diurnal cortisol concentration pattern due to allostatic overload. The purpose of this study was to examine if the diurnal cortisol pattern changed with exposure to work-related stressors according to the demand-control-support (DCS) and the effort-reward-imbalance (ERI) stress models. In 2007, 4467 Danish public service employees participated in a study on job stress and mental health, and 3217 were reexamined in 2009, using identical methods. DCS and ERI-exposures were assessed from self-administered questionnaires. Cortisol concentrations were assessed from saliva samples, one in the morning and one in the evening. Saliva sampling time distributions enabled us to estimate exposure effects on cortisol concentration patterns for the first two hours after awakening and for nine hours in the evening, and on the peak-to-nadir slope. Associations between the exposures and the diurnal cortisol pattern were examined by linear mixed model analyses, separately for DCS- and ERI-exposures, with mutual adjustment for main and composite variables of the stress model and a large set of potential confounders. DCS- and ERI-exposures were not associated with changes in the diurnal cortisol pattern. In contrast, many associations between potential confounders and cortisol were statistically significant, including the diurnal slope pattern assessed from saliva sampling times. We found no support for the hypothesis that DCS- or ERI- exposures are associated with changes of the diurnal pattern of cortisol concentrations in saliva samples.
We examined leisure-time physical activity (LTPA) and active commuting (AC) and their associations with subsequent sickness absence (SA) among young and early midlife employees. The 2017 Helsinki Health Study survey among employees of the City of Helsinki aged 19–39 was prospectively linked to register-based data on total, short- and long-term SA spells (2017–2020). LTPA (n=3618) and AC (n=3513) were assessed as weekly metabolic equivalent (MET) hours in 2017. LTPA was categorized into five groups based on intensity and weekly volume (inactivity, moderate, moderate-to-vigorous, vigorous and high vigorous) and AC into four groups (inactive, low moderate, moderate-to-vigorous, vigorous). Analyses were stratified by sex and adjusted for sociodemographic and lifestyle factors using negative binomial regression to estimate incidence rate ratios (IRRs) and their 95
The Effort–Reward Imbalance (ERI) model is widely used to explain work-related stress and its health consequences. In policing, ERI research has primarily focused on sworn officers, while civilian employees have received limited attention. The purpose of this study was to examine whether ERI variables are associated with mental health and occupational functioning among police employees, and whether these associations differ between sworn officers and civilian personnel. This cross-sectional study included sworn police officers and civilian employees in the Norwegian police. A random sample of 4000 employees was invited to complete an online survey, and 560 employees participated. Effort, reward, and overcommitment were measured with the 16-item short ERI questionnaire, and the ERI ratio was calculated from the effort and reward scales. Anxiety symptoms, depressive symptoms, work engagement, and job-related self-efficacy were assessed using separate questionnaires. Group differences were examined using analyses of covariance, and associations between ERI predictors and outcome variables were tested using hierarchical regression analyses with interaction terms for occupational role. In the covariate-adjusted analytic sample (N = 558), no significant differences were observed between sworn officers and civilian employees in ERI variables, mental health outcomes, or occupational functioning. Higher ERI ratio was associated with higher anxiety symptoms (β = 0.28) and depressive symptoms (β = 0.33) and with lower work engagement (β = − 0.27) and job-related self-efficacy (β = − 0.16). Overcommitment showed stronger associations with anxiety symptoms (β = 0.50) and depressive symptoms (β = 0.46) and was inversely associated with job-related self-efficacy (β = − 0.28) and work engagement (β = − 0.14). Occupational role did not moderate these associations. The findings support the ERI model by demonstrating consistent associations between effort–reward imbalance, overcommitment, mental health, and occupational functioning in policing. Neither the levels of the ERI variables nor their associations with the outcomes differed by occupational role, suggesting that ERI processes operate similarly across occupational categories within a highly regulated welfare-state context.
Deepwater Horizon oil spill (DWHOS) responders potentially experienced multiple stressors. We examined associations between DWHOS deployment-related stressor patterns and neurological and endocrine/metabolic conditions among U.S. Coast Guard active duty responders who completed post-deployment surveys (n = 3102). Deployment-related stressor patterns were identified using principal component analysis of self-reported stressors. Neurological and endocrine/metabolic outcomes were classified from military health encounter records. Associations between principal components (PCs) and incident outcomes (2010–2015) were estimated through Cox proportional hazards regression. A five-component solution explained 79.2
To examine effects of night work on low-grade systemic inflammation, measured as high-sensitivity C-reactive protein (hsCRP concentration), in hospital-employed women. We analyzed baseline data from 929 women in the 1001 nights-cohort. Seven self-reported metrics captured night work history (never, past, current), night work duration (years) and recency (time since last night shift), current schedule (e.g., permanent night or 2- or 3-shift work), and intensity (number of weekly and consecutive night shifts, and night shifts in the past six days). We measured hsCRP concentration in blood. Associations between night work and log-transformed hsCRP concentration were estimated using generalized linear models: Model 1 adjusted for age and education; Model 2 additionally for body mass index (BMI), blood pressure, and health behaviors; Model 3 further for sleep duration and quality. Permanent night workers had a 49
Thai sugarcane workers often work in very hot, humid conditions. This study investigated the effect of heat stress exposure on heat-related symptoms and severe heat-related symptoms associated with heat stroke in Thai sugarcane workers. Sugarcane workers in Nakhon Sawan Province, Thailand, recruited during cooler and hotter months of 2023 provided information on demographics, health behaviours, working conditions, and 21 heat-related symptoms, including 8 severe heat-related symptoms. Environmental heat was assessed using Wet-Bulb Globe Temperature (WBGT). Full shift time-weighted average effective WBGTs (WBGTeff-FS-TWA) were estimated and adjusted for clothing to represent heat stress exposure. Associations between heat stress exposure and symptom counts were examined using generalised negative binomial regression, adjusting for available confounders. Generalised binary logistic regression assessed associations between heat stress exposure and having ≥ 10 heat-related symptoms or ≥ 3 severe heat-related symptoms. The mean measured WBGT was 28.9 ± 2.6 °C. The mean WBGTeff-FS-TWA was 31.3 ± 2.8 °C, with more than 40
ObjectivesThis study aimed to investigate the associations between urinary metabolites of Volatile organic compounds (mVOCs) and serum Lactate dehydrogenase (LDH) levels in a representative sample of the U.S. adults.MethodsWe analyzed data from 4907 participants in NHANES 2011-2018. Seventeen urinary mVOCs were measured, and serum LDH was used as the outcome. Generalized linear models (GLM), restricted cubic splines (RCS), and weighted quantile sum (WQS) regression were used to assess linear, nonlinear, and mixture effects. Sensitivity analyses were conducted using urinary creatinine-corrected mVOC concentrations, and quantile g-computation (qgcomp) was applied as an alternative mixture modeling approach to validate the robustness of our findings. Furthermore, false discovery rate (FDR) correction was applied to account for multiple comparisons.ResultsSeveral mVOCs were significantly associated with serum LDH. Notably, 2MHA, 34MHA, ATCA, and CYMA showed robust inverse associations, while PHEM was positively associated with LDH. RCS models revealed non-linear exposure-response relationships for multiple mVOCs. WQS regression indicated that both positively and negatively weighted mVOCs contributed to LDH levels, with DHBMA as a major positive contributor and 34MHA as a negative contributor. Most associations remained stable after sensitivity analyses.ConclusionsThis study demonstrates that urinary mVOCs are associated with serum LDH levels, suggesting potential subclinical toxic effects of VOC exposure. These findings underscore the need for environmental risk management and further investigation into the biological pathways linking VOCs to systemic health outcomes.
Long-term hearing effects of occupational noise exposure below 85 dBA TWA remain insufficiently characterized in semiconductor manufacturing environments. This study evaluated longitudinal hearing-threshold changes among silicon wafer manufacturing workers exposed to moderate workplace noise over approximately 20 years. This retrospective cohort study examined serial pure-tone air-conduction audiometry (0.5–6 kHz) in 71 male semiconductor workers exposed to process-specific noise levels ranging from 72.2 to 80.9 dBA TWA. Participants were classified into normal-hearing (n = 53) and hearing-impaired (n = 18) groups according to Korean special health examination criteria and further categorized by manufacturing process: Process A (utilities), Process B (ingot processing), and Process C (wafer slicing). Longitudinal hearing-threshold changes were analyzed using repeated-measures ANOVA and compared with ISO 1999:2013 reference predictions. Both groups demonstrated significant deterioration in high-frequency hearing thresholds, particularly at 4–6 kHz (p < 0.001). Workers with normal baseline hearing showed threshold shifts of approximately 6–8 dB at 4 kHz and 8–10 dB at 6 kHz during follow-up, whereas workers with pre-existing hearing impairment demonstrated substantially greater progression. Process C, which had the highest recent exposure levels, showed the most pronounced longitudinal deterioration. Observed high-frequency threshold shifts were greater than conservative ISO 1999 reference predictions despite exposure levels below 85 dBA. Prolonged exposure to moderate occupational noise below current regulatory limits was associated with progressive high-frequency hearing deterioration in semiconductor manufacturing workers. These findings suggest that cumulative exposure duration and process-specific exposure characteristics should be considered in occupational hearing conservation programs.
Precarious employment (PE), characterized by job insecurity, instability, low wages, and limited access to social protections, has been linked to adverse health outcomes. This study examines whether PE, measured using a newly validated precarious employment index (PEI), is associated with high stress and poor self-rated health (SRH) in Danish workers. We conducted a cross-sectional study including 3339 Danish workers aged 18–45 years. The PEI captures six dimensions of working conditions: instability, salary, power and rights, work task planning, work time planning, and workers’ collective. PEI scores ranged from 0 (no PE) to 100 (most PE) and were dichotomized at the mean + 1 Standard Deviation (SD) into “no PE” and “PE”; 15
The health effects of high and moderate doses of ionizing radiation are recognized, but the impacts at lower doses are less clear. Medical workers represent the largest occupational group exposed to radiation. Herein, we examine mortality patterns in a Canadian cohort of medical workers, sex differences in risk, and trends in exposure over time. Annual whole-body effective doses for 301,740 medical workers between 1951 and 2018 were obtained from the Canadian National Dose Registry. Dose trends were characterised by job class and sex. Underlying cause of death was ascertained using linkage to mortality data through 2020. Standardized mortality ratios (SMRs) were estimated to compared the risk of mortality among 124,180 workers with with a lifetime cumulative dose > 0 mSv to the Canadian general population. Internal cohort comparisons incorporated person-time and events among unexposed workers. Poisson regression was used for internal cohort comparisons to explore healthy worker bias. The mean annual radiation dose among workers declined from 0.56 mSv during 1948–1977 to 0.09 mSv in 2000–2018. Compared to the general Canadian population, all-cause mortality was lower for both men (SMR = 0.54, 95
It is analyzed whether differences in how the daily usage time is determined in a population exposed to hand-transmitted vibration are the cause of discrepancies between exposure-response models constructed for vibration-induced white finger (VWF). The predictions of the models are then used to evaluate the one in ISO 5349-1:2001. Pooled analyses employing data from epidemiologic studies of vibration-exposed occupations deemed the most reliable, together with published ratios between daily tool or machine usage times determined by questionnaire or interview and measured values, are used to construct exposure-response relations. These models are compared to those in which the daily usage time is not compensated. Of 17 data points, for 7 the usage time ratio is greater than 1, and for the rest the ratio is equal to 1. Adjusting daily vibration exposures, expressed as A(8)-values, by means of such ratios, results in reductions of varying magnitude. However, the exposure-response models show minor changes, and the scatter in the data points previously observed remains. Methods for estimating 10 m/s^2 .
This study examined associations between urinary 3-diethyl-carbamoyl benzoic acid (DCBA), the principal metabolite of the insect repellent DEET, and liver fibrosis (LF) as well as non-alcoholic fatty liver disease (NAFLD) using a nationally representative sample. Network toxicology approaches were employed to explore underlying molecular mechanisms. We analyzed 5,960 adults from NHANES with DCBA measurements obtained through liquid chromatography-tandem mass spectrometry. LF severity was determined using NAFLD Fibrosis Score (NFS ≥ 0.676), whereas NAFLD was identified via sex-specific alanine aminotransferase criteria. Weighted logistic regression models incorporated progressive adjustment for demographic, anthropometric, and clinical factors. Network toxicology identified molecular targets, with molecular docking and dynamics simulations validating mechanistic pathways. DCBA exposure showed significant positive correlations with LF risk after full adjustment (OR = 1.254, 95
Currently, there is no standardized method to quantify musculoskeletal health of hand-arm vibration syndrome (HAVS). This study evaluated passive stiffness (PS) of the abductor pollicis brevis (APB) muscle among groundskeepers and examined the potential relationship of the PS with lifetime hand-arm vibration (HAV) exposure of the workers. PS of APB muscle was measured using a myotonometer among 17 groundskeepers and 10 office workers for 3 days. Study participants’ HAV exposure, demographic information, social history, and health-related information were pulled from our previous studies conducted in parallel with the present study. Linear mixed models were employed to estimate the association between lifetime HAV exposure dose and PS. The average PS for right and left hands was 509.7 N/m (range 402.2–752.9 N/m) and 501.7 N/m (range 380.4–660.7 N/m), respectively, in the exposure group and 422.0 N/m (range 365.0–517.2 N/m) and 430.3 N/m (range 359.2–591.9 N/m), respectively, in the reference group. A significant positive association between lifetime HAV exposure and PS was observed in the multivariable linear mixed model after adjusting for age, body mass index, and race/ethnicity (right hand: β = 6.972 and p-value = 0.0128; left hand: β = 9.039 and p-value = 0.0108). A significant association between lifetime HAV exposure and PS was found, supporting PS measurement using myotonometry as a promising health indicator for muscular disorders induced by HAV.
Malignant Mesotelioma (MM) is known for its association with asbestos exposure and long latency. Few studies examine a large series of MM patients investigating the past exposure intensity by autopsy findings. The aim was to describe the characteristics of MM cases diagnosed in Friuli Venezia Giulia, a region with several shipyards, and to assess past exposure levels by biological/histological markers, paying attention to some parameters of occupational exposure. For the period 1995–2023, all MM cases were retrieved from the Regional registry and information on diagnosis and exposure were evaluated. Pleural plaques (PP), lung fibrosis and asbestos bodies (ABs) counts were identified by autopsy reports and their relationship to past asbestos exposure was analyzed. Out of 1756 patients (1,487 men, 269 women; mean age at diagnosis 72.3 ± 10.4 years), autopsy reports were available for 896 cases (763 males and 133 females). PP, lung fibrosis and high ABs count (≥ 10,000 per gram of dry lung tissue) were more often present in men and in occupational exposure group than in women and in non-occupational one (p = 0.01). Among males occupationally exposed to asbestos (567 pleural and 33 peritoneal mesotheliomas), individuals with PP (66
So far there is no reference value for lead (Pb) established for the not occupationally exposed Ghanaian population. This is of special interest and will enable interpretation of data from high-risk areas like the Agbogbloshie e-waste dumpsite. The study suggests preliminary reference values for populations in Southern and Western Ghana. Blood specimens from non-exposed population were obtained in three key regions (Ashanti-Offinso, Western-Eikwe and Greater Accra-Accra). Three age groups were evaluated (15–24, 25–34, > 34 years). Individual habits (nutrition, occupation etc.) were documented using a standardized questionnaire. Graphite furnace atomic absorption spectrometry was used for Pb analysis. There was a total of 292 participants (Offinso = 124, Eikwe = 130, Accra = 38). The total mean Pb blood concentration of the Southern Ghanaian population was 43.3 µg/l ± 17.7, with a mean of 48.3 µg/l ± 17.2 for men and a mean of 38.1 µg/l ± 16.8 for women (P = .2.93–10). This value is twice as high as the mean Pb level among Germans, and higher than in most European countries. The 95th percentile for the total collective in Ghana was 81 µg/l and 76 µg/l for men and women, respectively. Based on the 95th percentile of the non-exposed population > 25 years data suggest a preliminary reference value for Pb in Ghana of 81 µg/l for men and of 76 µg/l for women. Since environmental load decreases with increasing distance when unleaded fuel became standard this should be re-evaluated in about 10 years. Future studies should include the eastern and northern regions of Ghana and the analysis of soil for its Pb content as environmental factor.
PurposeOrganophosphate (OP) pesticides are widely used in agriculture, vector control, and represent a global public health concern, particularly for occupationally exposed farmers and applicators. This study aimed to evaluate the associations among urinary dialkylphosphate (DAP) metabolites, cholinesterase activities, and butyrylcholinesterase (BuChE) polymorphisms in an indigenous population in Mexico.MethodsA cross-sectional study was conducted among 191 farmworkers. Data were collected using a structured questionnaire addressing sociodemographic characteristics, lifestyle factors, pesticide exposure, and dietary intake. Venous blood and urine samples were obtained to determine cholinesterase activities and urinary DAP concentrations, respectively.ResultsDetectable urinary DAP levels were identified, with dimethylthiophosphate (DMTP) as the predominant metabolite. BuChE activity was significantly associated with dietary lipid and carbohydrate intake. A high prevalence of ancestral genotypes was observed in the BuChE gene. Age-stratified analyses demonstrated differences in cholinesterase activities, and males with low BuChE activity exhibited higher urinary DAP metabolite concentrations.ConclusionThese findings highlight variability in OP pesticide metabolite levels and their relationships with dietary factors and genetic background among indigenous agricultural workers. Improved understanding of these interactions is essential for mitigating exposure-related health risks in vulnerable populations.
This study aimed to determine whether workers in fixed chimney Bull’s trench kilns (FCBTK) experience greater occupational exposure to air pollutants and more pronounced respiratory impairment than those in zigzag kilns, and to evaluate how seasonal production variations affect the relationship between exposure and respiratory outcomes. We hypothesized that FCBTK workers would demonstrate higher pollutant exposure and greater respiratory dysfunction, with seasonal peaks exacerbating these differences. A cross-sectional comparative study was conducted in Jaranwala, district Faisalabad, between April to August (Low) and November to January (High) in 2022–2023, among 160 male workers from 20 kilns (10 FCBTK, 10 zigzag). Ambient PM2.5, PM10, CO, and SO2 were measured at kiln worksites using calibrated portable monitors. Spirometry was performed according to ATS/ERS guidelines and expressed as
Psychosocial working conditions influence the risk for sickness absence days. These relationships can differ for employees with common mental disorders (CMDs). This study therefore investigates relationships between psychosocial working conditions and sickness absence days in employees reporting CMD symptoms. Data of participants of a randomized controlled trial are investigated (n = 529). The Copenhagen Psychosocial Questionnaire assessed 12 scales of working conditions at baseline. The outcomes number of sickness absence days were assessed nine and 15 months later, as well as during the follow-up period. Negative binomial regression analyses were adjusted for several factors and were conducted for imputed data and supplemented by complete case analyses. Influence at work was associated with lower risks of sickness absence days nine (RR= -0.009, CI= − 0.018; − 0.001) and 15 months later (RR= − 0.008, CI= − 0.015; 0.000). Dissolution (i.e., reporting to work outside of work hours or being available for colleagues during free time) was associated with lower risks of sickness absence days during the follow-up period. Complete case analyses showed positive associations between social support and sickness absence days nine (RR = 0.01, CI = 0.0; 0.02; n = 377) and 15 months later (RR = 0.01, CI = 0.0; 0.03; n = 320). Among employees reporting symptoms of CMDs, influence at work and dissolution predicted sickness absence days for different time periods. However, many psychosocial working conditions showed no such relevance, indicating that other factors may be more relevant in regard of sickness absence days among this particular group of employees. The randomized controlled trial was registered at the German Clinical Trial Register on 01.03.2021 (DRKS00023049; https://drks.de/search/en/trial/DRKS00023049).
Traffic-related air pollution (TRAP) poses significant health risks to children. While adverse outcomes have been reported, the biological mechanisms underlying these effects remain unclear. This study investigates the association between TRAP exposure and DNA methylation (DNAm) changes in TNFα and CYP1A1 genes as potential epigenetic markers among school children in Malaysia. A cross-sectional comparative study was conducted involving 248 children aged 7–11 years from high-traffic (HT) and low-traffic (LT) areas in the Klang Valley. Environmental monitoring was performed at both schools and residences to measure levels of PM10, PM2.5, PM1, NO2, SO2, O3, CO, total volatile organic compounds (TVOC), and black carbon (BC). Dietary intake and other potential confounders were assessed via validated questionnaires. Saliva samples were collected and analyzed for DNAm status using methylation-specific polymerase chain reaction (MS-PCR) targeting TNFα and CYP1A1 genes. Pollutant levels were significantly elevated in HT schools (p < 0.001), whereas LT schools recorded higher CO2 concentrations. Children in HT areas had significantly higher methylation in TNFα (54.0
To examine associations between maternal occupational physical activity (OPA) during pregnancy and childhood cancer risk in offspring. The study population included all cancer cases born in Denmark between 1968 and 2013, aged 0–19 at diagnosis between 1968 and 2016 (N = 7077). Sex- and birth-year matched controls (ratio 1:25) were randomly selected from the Central population registry. maternal OPA was assessed by a job exposure matrix based on the nordic occupational cancer study (score: heavy or rather heavy physical work versus all other levels). Unconditional logistic regression adjusted for potential confounders was used to estimate effects. Dose-response relationships examined by OPA exposure probability groups (high, medium, low versus no exposure). Medium cumulative maternal OPA exposure was associated with an average 8
