Description: Objectives Noise-induced hearing loss is one of the most serious occupational diseases worldwide. It is caused by interactions between environmental and genetic factors. The purpose of this study was to examine the association between the genetic susceptibility of the eye absent homolog 4 (EYA4) gene and the risk of developing noise-induced hearing loss in China. Methods A case–control association study was carried out with 326 hearing loss cases and 326 controls matched with age and duration of noise exposure, drawn from a cohort of steel workers. Five single nucleotide polymorphisms (SNPs) in the EYA4 were selected and genotyped. Logistic regression was performed to analyse the main effect of genotypes and interactions between genotypes and individual/environmental factors adjusted for confounding factors. Moreover, generalised multiple dimensionality reduction was applied to further detect interaction among the 5 selected SNPs. Results Analysis revealed that locus polymorphism of rs3813346 was associated with the risk of developing noise-induced hearing loss in the dominance model, the codominance model and the addictive model (p=0.004, 0.009 and 0.003, respectively). A significant interaction between rs9321402 and cumulative noise exposure was found (p=0.002). A significant main effect p value (p=0.006) was obtained in the high-level exposure group (cumulative noise exposure ≥98 dB(A)). Generalised multiple dimensionality reduction indicated that the combined interaction of the 2 loci—rs3813346 and rs9493627—significantly affected the incidence of noise-induced hearing loss. Conclusions The research suggests that EYA4 genetic variant and its interaction with noise levels may modify the susceptibility to develop noise-induced hearing loss in Chinese population.

Description: Background MRI has developed into one of the most important medical diagnostic imaging modalities, but it exposes staff to static magnetic fields (SMF) when present in the vicinity of the MR system, and to radiofrequency and switched gradient electromagnetic fields if they are present during image acquisition. We measured exposure to SMF and motion-induced time-varying magnetic fields (TVMF) in MRI staff in clinical practice in the UK to enable extensive assessment of personal exposure levels and variability, which enables comparison to other countries. Methods 8 MRI facilities across National Health Service sites in England, Wales and Scotland were included, and staff randomly selected during the days when measurements were performed were invited to wear a personal MRI-compatible dosimeter and keep a diary to record all procedures and tasks performed during the measured shift. Results 98 participants, primarily radiographers (71%) but also other healthcare staff, anaesthetists and other medical staff were included, resulting in 149 measurements. Average geometric mean peak SMF and TVMF exposures were 448 mT (range 20–2891) and 1083 mT/s (9–12 355 mT/s), and were highest for radiographers (GM=559 mT and GM=734 mT/s). Time-weighted exposures to SMF and TVMF (GM=16 mT (range 5–64) and GM=14 mT/s (range 9–105)) and exposed-time-weighted exposures to SMF and TVMF (GM=27 mT (range 11–89) and GM=17 mT/s (range 9–124)) were overall relative low—primarily because staff were not in the MRI suite for most of their shifts—and did not differ significantly between occupations. Conclusions These results are comparable to the few data available from the UK but they differ from recent data collected in the Netherlands, indicating that UK staff are exposed for shorter periods but to higher levels. These data indicate that exposure to SMF and TVMF from MRI scanners cannot be extrapolated across countries.

Description: Background The current knowledge on respiratory work disability is based on studies that used crude categories of exposure. This may lead to a loss of power, and does not provide sufficient information to allow targeted workplace interventions and follow-up of patients with respiratory symptoms. Objectives The aim of this study was to identify occupations and specific exposures associated with respiratory work disability. Methods In 2013, a self-administered questionnaire was mailed to a random sample of the general population, aged 16–50, in Telemark County, Norway. We defined respiratory work disability as a positive response to the survey question: ‘Have you ever had to change or leave your job because it affected your breathing?’ Occupational exposures were assessed using an asthma-specific job-exposure matrix, and comparison of risks was made for cases and a median of 50 controls per case. Results 247 workers had changed their work because of respiratory symptoms, accounting for 1.7% of the respondents ever employed. The ‘breath-taking jobs’ were cooks/chefs: adjusted OR 3.6 (95% CI 1.6 to 8.0); welders: 5.2 (2.0 to 14); gardeners: 4.5 (1.3 to 15); sheet metal workers: 5.4 (2.0 to 14); cleaners: 5.0 (2.2 to 11); hairdressers: 6.4 (2.5 to 17); and agricultural labourers: 7.4 (2.5 to 22). Job changes were also associated with a variety of occupational exposures, with some differences between men and women. Conclusions Self-report and job-exposure matrix data showed similar findings. For the occupations and exposures associated with job change, preventive measures should be implemented.

Description: Background The association between lung cancer and occupational exposure to organic solvents is discussed. Since different solvents are often used simultaneously , it is difficult to assess the role of individual substances. Objectives The present study is focused on an in-depth investigation of the potential association between lung cancer risk and occupational exposure to a large group of organic solvents, taking into account the well-known risk factors for lung cancer, tobacco smoking and occupational exposure to asbestos. Methods We analysed data from the Investigation of occupational and environmental causes of respiratory cancers (ICARE) study, a large French population-based case–control study, set up between 2001 and 2007. A total of 2276 male cases and 2780 male controls were interviewed, and long-life occupational history was collected. In order to overcome the analytical difficulties created by multiple correlated exposures, we carried out a novel type of analysis based on Bayesian profile regression. Results After analysis with conventional logistic regression methods, none of the 11 solvents examined were associated with lung cancer risk. Through a profile regression approach, we did not observe any significant association between solvent exposure and lung cancer. However, we identified clusters at high risk that are related to occupations known to be at risk of developing lung cancer, such as painters. Conclusions Organic solvents do not appear to be substantial contributors to the occupational risk of lung cancer for the occupations known to be at risk.

Description: Background To date, the association of the neurotoxic agent cadmium (Cd) with depression in elderly people has been poorly evaluated. By investigating the relationship between blood cadmium levels and scores on a depression screening test, we aimed to investigate the impact of cadmium exposure on elderly depression. Methods From 2008 to 2010, a total of 395 elderly participants residing in Seoul, Korea, were evaluated 3 times. Demographic data and lifestyle information were obtained via a systemised questionnaire, and blood samples were collected for analysis. Participants underwent the Korean Version of the Short Form Generic Depression Scale test (SGDS-K) for screening depression and associations were estimated using logistic regression models adjusted for potential confounders. Results Blood cadmium levels were associated with depressive symptoms in the first visit data analysis. By analysing the first visit data, the highest quartile blood cadmium group (Q4) showed increased risk for depressive symptoms compared to the lowest quartile group (Q1) (OR 3.50, 95% CI 1.22 to 10.00). However, the data of the second and third visits suggested that blood cadmium may be protective against depressive symptoms (second visit data, Q4 vs Q1, OR 0.78, 95% CI 0.19 to 3.14; third visit data, Q4 vs Q1, OR 0.58, 95% CI 0.04 to 8.77). Conclusions Owing to inconsistent results in analyses between blood cadmium levels and depressive symptoms, we cannot conclude any solid association between blood cadmium levels and depressive symptoms in the elderly population. To clarify the relationship, other prospective studies are needed in the future.

Description: Objective Occupationally acquired noise-induced hearing loss (NIHL) is the most prevalent occupational disease in Austria and among the most common in many other countries. Because of the wide variation in hearing loss after equivalent exposures it has long been assumed that some individuals are more vulnerable to occupational NIHL than others. Earlier attempts to define predictors of NIHL before starting occupational noise exposure have largely failed. We present results of a prospective study evaluating the potential of temporary threshold shift (TTS) after a test exposure to predict NIHL. Methods Between 1982 and 1989, overall 311 apprentices were included into a prospective study during their initial health screening visit. At this occasion, a standardised noise exposure was applied (20 min, 200–500 Hz, 100 dBA) and the TTS at 4 kHz was determined during at least 10 min after exposure. Hearing loss was monitored at follow-up visits every 3–5 years. Follow-up was 13 years on average. Results Permanent threshold shift was predicted by duration of noise exposure, frequency of wearing noise protectors and especially by the initial TTS at 4 kHz. Using 14 dB TTS as a cut-off had 82% sensitivity and 53% specificity to predict 20 dB or higher levels of NIHL. Conclusions The TTS model can be successfully applied as a method to detect individuals at greater risk of occupational NIHL. It is recommended to routinely include such a procedure into initial workers’ examinations for suitability to work under occupational noise conditions and for counselling on the use of hearing protectors.

Description: Objectives To estimate the numbers of workers exposed to known and suspected occupational carcinogens in Canada, building on the methods of CARcinogen EXposure (CAREX) projects in the European Union (EU). Methods CAREX Canada consists of estimates of the prevalence and level of exposure to occupational carcinogens. CAREX Canada includes occupational agents evaluated by the International Agency for Research on Cancer as known, probable or possible human carcinogens that were present and feasible to assess in Canadian workplaces. A Canadian Workplace Exposure Database was established to identify the potential for exposure in particular industries and occupations, and to create exposure level estimates among priority agents, where possible. CAREX EU data were reviewed for relevance to the Canadian context and the proportion of workers likely to be exposed by industry and occupation in Canada was assigned using expert assessment and agreement by a minimum of two occupational hygienists. These proportions were used to generate prevalence estimates by linkage with the Census of Population for 2006, and these estimates are available by industry, occupation, sex and province. Results CAREX Canada estimated the number of workers exposed to 44 known, probable and suspected carcinogens. Estimates of levels of exposure were further developed for 18 priority agents. Common exposures included night shift work (1.9 million exposed), solar ultraviolet radiation exposure (1.5 million exposed) and diesel engine exhaust (781 000 exposed). Conclusions A substantial proportion of Canadian workers are exposed to known and suspected carcinogens at work.

Description: Objectives To examine vascular endothelial growth factor (VEGF) and PGE2 levels in urine from the copper smelting workers exposed to arsenic and analyse the relationships between urinary VEGF or PGE2 level and arsenical metabolites. Methods The study was conducted in a group of 106 copper-smelting male workers. Information about each subject was obtained by questionnaire, inorganic As (iAs), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), VEGF and prostaglandin E2 (PGE2) in urine were determined. Standing height, body weight, and blood pressure were measured. Results According to the urine arsenic levels, participants were separated into three groups: Group 1: urine total arsenic 〈35 mg/L, Group 2: 35–100 mg/L, and Group 3: 〉100 mg/L. The median levels of urinary VEGF and PGE2 in Groups 1, 2 and 3 were 10.57 and 1032.0 pg/mL, 24.39 and 1060.9 pg/mL, and 49.0 and 1330.4 pg/mL, respectively. Urinary VEGF levels were positive associated with arsenical metabolites (iAs, MMA, DMA and TAs). Additionally, urinary VEGF and PGE2 levels were all correlated positively with the urinary MMA% (r=0.221, p=0.026 and r=0.206, p=0.037). While urinary VEGF was negatively with DMA% and secondary methylation index (r=–0.242, p=0.014 and r=–0.214, p=0.030, respectively). Conclusions Urinary VEGF and PGE2 levels increased in arsenic exposure copper smelting workers, and urinary VEGF levels are well associated with the urinary arsenicals. This finding may provide useful information for developing measurement, prevention and treatment of damage induced by arsenic in the future.

Description: Aims The relation between Dupuytren's contracture and occupational exposure to hand-transmitted vibration (HTV) has frequently been debated. We explored associations in a representative national sample of workers with well-characterised exposure to HTV. Methods We mailed a questionnaire to 21 201 subjects aged 16–64 years, selected at random from the age-sex registers of 34 general practices in Great Britain and to 993 subjects chosen randomly from military pay records, asking about occupational exposure to 39 sources of HTV and about fixed flexion contracture of the little or ring finger. Analysis was restricted to men at work in the previous week. Estimates were made of average daily vibration dose ( A (8) root mean squared velocity (rms)) over that week. Associations with Dupuytren's contracture were estimated by Poisson regression, for lifetime exposure to HTV and for exposures in the past week 〉 A (8) of 2.8 ms –2 rms. Estimates of relative risk (prevalence ratio (PR)) were adjusted for age, smoking status, social class and certain manual activities at work. Results In all 4969 eligible male respondents supplied full information on the study variables. These included 72 men with Dupuytren's contracture, 2287 with occupational exposure to HTV and 409 with A (8)〉2.8 ms –2 in the past week. PRs for occupational exposure to HTV were elevated 1.5-fold. For men with an A (8)〉2.8 ms –2 in the past week, the adjusted PR was 2.85 (95% CI 1.37 to 5.97). Conclusions Our findings suggest that risk of Dupuytren's contracture is more than doubled in men with high levels of weekly exposure to HTV.

Description: Objectives An ‘information gap’ has been identified regarding the effects of chronic disease on occupational injury risk. We investigated the association of ischaemic heart disease, hypertension, diabetes, depression and asthma with acute occupational injury in a cohort of manufacturing workers from 1 January 1997 through 31 December 2007. Methods We used administrative data on real-time injury, medical claims, workplace characteristics and demographics to examine this association. We employed a piecewise exponential model within an Andersen–Gill framework with a frailty term at the employee level to account for inclusion of multiple injuries for each employee, random effects at the employee level due to correlation among jobs held by an employee, and experience on the job as a covariate. Results One-third of employees had at least one of the diseases during the study period. After adjusting for potential confounders, presence of these diseases was associated with increased hazard of injury: heart disease (HR 1.23, 95% CI 1.11 to 1.36), diabetes (HR 1.17, 95% CI 1.08 to 1.27), depression (HR 1.25, 95% CI 1.12 to 1.38) and asthma (HR 1.14, 95% CI 1.02 to 1.287). Hypertension was not significantly associated with hazard of injury. Associations of chronic disease with injury risk were less evident for more serious reportable injuries; only depression and a summary health metric derived from claims remained significantly positive in this subset. Conclusions Our results suggest that chronic heart disease, diabetes and depression confer an increased risk for acute occupational injury.