Lifetime Occupational History Research Articles

Occupational exposure to ionizing radiation and risk of lymphoma subtypes: results of the Epilymph European case-control study

BackgroundEvidence linking risk of lymphoma and B-cell lymphoma subtypes to ionizing radiation is inconclusive, particularly at low exposure levels.MethodsWe investigated risk of lymphoma (all subtypes), B-cell lymphomas, and its major subtypes, associated with low-level occupational exposure to ionizing radiation, in 2346 lymphoma cases and 2463 controls, who participated in the multicenter EpiLymph case-control study. We developed a job-exposure matrix to estimate exposure to ionizing radiation, distinguishing between internal and external radiation, and we applied it to the lifetime occupational history of study subjects, We calculated the Odds Ratio (OR) and its 95% confidence interval (95% CI) for lymphoma (all subtypes combined), B-cell lymphoma, and its major subtypes using unconditional, polytomous logistic regression adjusting for age, gender, and education.ResultsWe did not observe an association between exposure metrics of external and internal radiation and risk of lymphoma (all subtypes), nor with B-cell lymphoma, or its major subtypes, at the levels regularly experienced in occupational settings. An elevated risk of diffuse large B cell lymphoma was observed among the most likely exposed study subjects with relatively higher exposure intensity, which would be worth further investigation.ConclusionsFurther investigation is warranted on risk of B cell lymphoma subtypes associated with low-level occupational exposure to external ionizing radiation, and to clarify whether lymphoma should be included among the cancer outcomes related to ionizing radiation.

Silica and asbestos exposure at work and the risk of bladder cancer in Canadian men: a population-based case-control study

BackgroundSilica and asbestos are recognized lung carcinogens. However, their role in carcinogenesis at other organs is less clear. Clearance of inhaled silica particles and asbestos fibers from the lungs may lead to translocation to sites such as the bladder where they may initiate carcinogenesis. We used data from a Canadian population-based case-control study to evaluate the associations between these workplace exposures and bladder cancer.MethodsData from a population-based case-control study were used to characterize associations between workplace exposure to silica and asbestos and bladder cancer among men. Bladder cancer cases (N = 658) and age-frequency matched controls (N = 1360) were recruited within the National Enhanced Cancer Surveillance System from eight Canadian provinces (1994–97). Exposure concentration, frequency and reliability for silica and asbestos were assigned to each job, based on lifetime occupational histories, using a combination of job-exposure profiles and expert review. Exposure was modeled as ever/never, highest attained concentration, duration (years), highest attained frequency (% worktime) and cumulative exposure. Odds ratios (OR) and their 95% confidence intervals (CI) were estimated using adjusted logistic regression.ResultsA modest (approximately 20%) increase in bladder cancer risk was found for ever having been exposed to silica, highest attained concentration and frequency of exposure but this increase was not statistically significant. Relative to unexposed, the odds of bladder cancer were 1.41 (95%CI: 1.01–1.98) times higher among men exposed to silica at work for ≥27 years. For asbestos, relative to unexposed, an increased risk of bladder cancer was observed for those first exposed ≥20 years ago (OR:2.04, 95%CI:1.25–3.34), those with a frequency of exposure of 5–30% of worktime (OR:1.45, 95%CI:1.06–1.98), and for those with < 10 years of exposure at low concentrations (OR:1.75, 95%CI:1.10–2.77) and the lower tertile of cumulative exposure (OR:1.69, 95%CI:1.07–2.65). However, no clear exposure-response relationships emerged.ConclusionsOur results indicate a slight increase in risk of bladder cancer with exposure to silica and asbestos, suggesting that the effects of these agents are broader than currently recognized. The findings from this study inform evidence-based action to enhance cancer prevention efforts, particularly for workers in industries with regular exposure.

Diesel exhaust and bladder cancer risk by pathologic stage and grade subtypes

BackgroundThe International Agency for Research on Cancer (IARC) classifies diesel engine exhaust as carcinogenic to humans based on sufficient evidence for lung cancer. IARC noted, however, an increased risk of bladder cancer (based on limited evidence). ObjectiveTo evaluate the association between quantitative, lifetime occupational diesel exhaust exposure and risk of urothelial cell carcinoma of the bladder (UBC) overall and according to pathological subtypes. MethodsData from personal interviews with 1944 UBC cases, as well as formalin-fixed paraffin-embedded tumor tissue blocks, and 2135 controls were pooled from two case-control studies conducted in the U.S. and Spain. Lifetime occupational histories combined with exposure-oriented questions were used to estimate cumulative exposure to respirable elemental carbon (REC), a primary surrogate for diesel exhaust. Unconditional logistic regression and two-stage polytomous logistic regression were used to calculate odds ratios (ORs) and 95% confidence intervals (CIs), adjusting for smoking and other risk factors. ResultsExposure to cumulative REC was associated with an increased risk of UBC; workers with cumulative REC >396 μg/m3-years had an OR of 1.61 (95% CI, 1.08–2.40). At this level of cumulative exposure, similar results were observed in the U.S. and Spain, OR = 1.75 (95% CI, 0.97–3.15) and OR = 1.54 (95% CI, 0.89–2.68), respectively. In lagged analysis, we also observed a consistent increased risk among workers with cumulative REC >396 μg/m3-years (range of ORs = 1.52–1.93) for all lag intervals evaluated (5–40 years). When we accounted for tumor subtypes defined by stage and grade, a significant association between diesel exhaust exposure and UBC was apparent (global test for association p = 0.0019). ConclusionsCombining data from two large epidemiologic studies, our results provide further evidence that diesel exhaust exposure increases the risk of UBC.

&lt;p&gt;Lifetime Occupational History, Respiratory Symptoms and Chronic Obstructive Pulmonary Disease: Results from a Population-Based Study&lt;/p&gt;

PurposeTo ascertain the effect of lifelong occupational history, ambient air pollution, and biochemically verified smoking status on chronic obstructive pulmonary disease (COPD) in a general population of one the largest cities in Central Asia, Almaty.Patients and methods1500 adults (median age 49, interquartile range (IQR) 28 years), 50% females, were randomly selected from a registry of enlisted population of a primary care facility in Almaty, Kazakhstan and they filled in the questionnaire on demographics, respiratory symptoms (CAT and mMRC), smoking status, verified by exhaled carbon monoxide, and detailed lifetime occupational history. COPD was defined as postbronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity (FVC) below lower limit of normal (LLN) using Belintelmed MAS-2 spirometer (Belarus).Results230 (15%) subjects had CAT≥10; 136 (9%) participants had mMRC score ≥2. Greater CAT score was associated with age, smaller income, and less exercise, but not with smoking or living closer to a major road. 26% of the population was ever exposed to vapors, gases, dusts, and fumes (VGDF). In age group 40 years and above (N=1024), COPD was found in 57 participants (prevalence 5.6%), more in men (8.7% vs 3.4%). In the multivariate model adjusted for age, sex, ever-smoking, income, and exercise, any exposure to VGDF increased the odds of COPD (odds ratio (OR) 1.71; 95% confidence interval (CI) 1.03; 2.84), more in the highest exposure category (OR 2.36 (95% CI 1.20; 4.66)).ConclusionLifetime exposure to VGDF, found in ¼ of the general population, increased the odds of COPD independent of smoking by 71%.

Is radiographic lumbar spondylolisthesis associated with occupational exposures? Findings from a nested case control study within the Wakayama spine study

BackgroundTo explore the relationship between radiographic spondylolisthesis and occupational factors in a case-control study nested within the Wakayama Spine Study (WSS).MethodsThe WSS is a cross-sectional observational study amongst Japanese adults. All participants completed a lifetime occupational history and underwent X-rays of the lumbar spine (L1-S1) according to a pre-defined protocol. One trained surgeon graded the presence of a spondylolisthesis based upon ≥5% anterior or posterior slip at one or more levels. Cases, with lumbar spondylolisthesis, were compared with controls without, for their principal occupation and occupational exposures.ResultsIn total, data were available for 722 adults (245 men and 477 women), mean age 70.1 (range 53–93) years. According to the pre-defined radiographic criteria, 117 were defined with spondylolisthesis (cases), leaving 605 controls. Cases were not significantly different from controls for age, gender, BMI, smoking or alcohol intake. However, cases were more than twice as likely to report occupational driving ≥4 h/day (OR 2.39, 95% CI 1.08–5.27) after adjustment for age, gender and BMI. Additionally, after stratification by age using 75 years as a cut-point, cases were more than 3-fold more likely to report having worked in the agricultural/ fishing industries (OR 3.47, 95% CI 1.29–9.29) among those aged < 75 years. A reduced risk of being a case was associated with climbing slopes/steps and walking.ConclusionsA history of occupational driving and working in the agricultural/fishing industry were associated with radiographic spondylolisthesis in this cross-sectional population study. This finding requires further evaluation in longitudinal studies.

RE: “ASSOCIATIONS OF ELECTRIC SHOCK AND EXTREMELY LOW-FREQUENCY MAGNETIC FIELD EXPOSURE WITH THE RISK OF AMYOTROPHIC LATERAL SCLEROSIS: THE EURO-MOTOR PROJECT”

We explored the associations of occupational exposure to extremely low-frequency magnetic fields (ELF-MF) and electric shocks with the risk of amyotrophic lateral sclerosis (ALS) in a pooled case-control study (European Multidisciplinary ALS Network Identification to Cure Motor Neurone Degeneration (Euro-MOTOR)) of data from 3 European countries. ALS patients and population-based controls were recruited in Ireland, Italy, and the Netherlands between 2010 and 2015. Lifetime occupational and lifestyle histories were obtained using structured questionnaires. We applied previously developed job exposure matrices assigning exposure levels to ELF-MF and potential for electric shocks. Odds ratios and 95% confidence intervals were estimated by means of logistic regression for exposure to either ELF-MF or electric shocks, adjusted for age, sex, study center, education, smoking, and alcohol consumption and for the respective other exposure. Complete occupational histories and information on confounding variables were available for 1,323 clinically confirmed ALS cases and 2,704 controls. Both ever having had exposure to ELF-MF above the background level (odds ratio = 1.16, 95% confidence interval: 1.01, 1.33) and ever having had potential exposure above background for electric shocks (odds ratio = 1.23, 95% confidence interval: 1.05, 1.43) were associated with ALS. Adjustment for the respective other exposure resulted in similar risk estimates. Heterogeneity in risks across study centers was significant for both exposures. Our findings support possible independent associations of occupational exposure to ELF-MF and electric shocks with the risk of ALS.

Shift Work Patterns, Chronotype, and Epithelial Ovarian Cancer Risk.

Shift work causing circadian disruption is classified as a "probable carcinogen" and may contribute to the pathogenesis of hormone-sensitive cancers. This study investigated shift work exposure in relation to epithelial ovarian cancer (EOC) risk. In a population-based case-control study with 496 EOC cases and 906 controls, lifetime occupational histories were collected and used to calculate cumulative years of shift work exposure, average number of night shifts per month, and average number of consecutive night shifts per month. ORs and 95% confidence intervals (CI) for associations with EOC risk were estimated using logistic regression. Associations were also examined according to chronotype and menopausal status. More than half of the cases (53.4%) and controls (51.7%) worked evening and/or night shifts. There was no clear pattern of increasing EOC risk with increasing years of shift work; the adjusted OR of EOC comparing the highest shift work category versus never working shift work was 1.20 (95% CI, 0.89-1.63). This association was more pronounced among those self-identified as having a "morning" chronotype (OR, 1.64; 95% CI, 1.01-2.65). Associations did not greatly differ by menopausal status. These results do not strongly demonstrate a relationship between shift work and EOC risk. This study collected detailed shift work information and examined shift work patterns according to shift times and schedules. The findings highlight that chronotype should be considered in studies of shift work as an exposure.

Multicentre, population-based, case–control study of particulates, combustion products and amyotrophic lateral sclerosis risk

ObjectiveTo investigate whether exposure to particulates and combustion products may explain the association between certain occupations and amyotrophic lateral sclerosis (ALS) risk in a large, multicentre, population-based, case–control study, based...

Associations of Electric Shock and Extremely Low-Frequency Magnetic Field Exposure With the Risk of Amyotrophic Lateral Sclerosis.

We explored the associations of occupational exposure to extremely low-frequency magnetic fields (ELF-MF) and electric shocks with the risk of amyotrophic lateral sclerosis (ALS) in a pooled case-control study (European Multidisciplinary ALS Network Identification to Cure Motor Neurone Degeneration (Euro-MOTOR)) of data from 3 European countries. ALS patients and population-based controls were recruited in Ireland, Italy, and the Netherlands between 2010 and 2015. Lifetime occupational and lifestyle histories were obtained using structured questionnaires. We applied previously developed job exposure matrices assigning exposure levels to ELF-MF and potential for electric shocks. Odds ratios and 95% confidence intervals were estimated by means of logistic regression for exposure to either ELF-MF or electric shocks, adjusted for age, sex, study center, education, smoking, and alcohol consumption and for the respective other exposure. Complete occupational histories and information on confounding variables were available for 1,323 clinically confirmed ALS cases and 2,704 controls. Both ever having had exposure to ELF-MF above the background level (odds ratio = 1.16, 95% confidence interval: 1.01, 1.33) and ever having had potential exposure above background for electric shocks (odds ratio = 1.23, 95% confidence interval: 1.05, 1.43) were associated with ALS. Adjustment for the respective other exposure resulted in similar risk estimates. Heterogeneity in risks across study centers was significant for both exposures. Our findings support possible independent associations of occupational exposure to ELF-MF and electric shocks with the risk of ALS.

Association between Occupational Exposure to Textile Fibre Dusts and Lung Cancer in a Population-Based Case-Control Study in Montreal: A Preliminary Analysis Comparing Results from Three Analytical Methods

Objectives: To compare results estimated using two causal inference methods, inverse probability of exposure weighting (IPEW) and G-computation, to that estimated using the conventional multivariable logistic regression, on the association between occupational exposure to textile fibre dusts and lung cancer risk.Methods: A population-based case-control study on lung cancer was conducted from 1996 to 2001 in Montreal, Canada. Cases were individuals diagnosed with incident lung cancer and population controls were randomly selected from electoral lists and frequency-matched to cases by age, sex and electoral district. Questionnaires on lifetime occupational history, smoking and demographic characteristics were collected during in-person interview. Experts reviewed subjects&amp;#8217; work history and assessed exposure to 294 agents, including textile fibre dusts. Odds ratios (OR) and their 95% confidence intervals (CIs) for the association between ever exposure to textile fibre dusts and lung cancer risk were estimated using three different methods: 1) IPEW, 2) G-computation, and 3) conventional multivariable regression.Results: The two causal inference methods produced higher point estimates (ORIPEW&amp;#61;1.17, 95% CI&amp;#61;0.86-1.57; ORG-computation&amp;#61;1.11, 95% CI&amp;#61;0.80-1.49) compared to that estimated using the conventional multivariable logistic regression (OR&amp;#61;0.87, 95% CI&amp;#61;0.68-1.11). However, all three sets of OR results were close to the null value.Conclusion: The different methods provided rather similar results, albeit not identical. They are compatible with a null association between occupational exposure to textile fibre dusts and lung cancer.

Occupational Exposure to Diesel and Gasoline Engine Exhausts and the Risk of Kidney Cancer in Canadian Men.

IntroductionKidney cancer is the fifth most common incident cancer in Canadian men. Diesel and gasoline exhausts are common workplace exposures that have been examined as risk factors for non-lung cancer sites, including the kidney, but limitations in exposure assessment methods have contributed to inconsistent findings. The objective of this study was to assess the relationship between occupational gasoline and diesel engine exhausts and the risk of kidney cancer in men.MethodsThe National Enhanced Cancer Surveillance System (NECSS) is a Canadian population-based case–control study conducted in 1994–1997. Incident kidney cancer cases were identified using provincial registries, while the control series was identified through random-digit dialing, or provincial administrative databases. Self-reported questionnaires were used to obtain information on lifetime occupational history and cancer risk factors. Two hygienists, blinded to case status, coded occupational histories for diesel and gasoline exhaust exposures using concentration, frequency, duration, and reliability. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) separately by exhaust type. The separate and combined impacts of both engine exhausts were also examined. ORs were adjusted for age, province, body mass index, occupational secondhand smoke exposure, and education.ResultsOf the kidney cancer cases (n = 712), 372 (52%) had exposure to both exhausts at some point, and 984 (40%) of the controls (n = 2457) were ever exposed. Workers who had ever been exposed to engine exhausts were more likely to have kidney cancer than those who were never exposed (OR diesel = 1.23, 95% CI = 0.99–1.53; OR gasoline = 1.51, 95% CI = 1.23–1.86). Exposure to gasoline exhaust was consistently associated with kidney cancer in a dose–response manner (P value for trends in highest attained and cumulative exposure both <0.0001). Those men with high cumulative exposure to both gasoline and diesel exhaust had a 76% increased odds of kidney cancer (95% CI = 1.27–2.43).ConclusionsThis study provides evidence that occupational gasoline, and to a lesser extent, diesel exhaust exposure may increase the risk of kidney cancer.

Occupational exposure to organic solvents and risk of breast cancer: Results of the CECILE study, a population-based case-control study in France

Introduction Breast cancer is the leading cause of cancer death in women worldwide. Its incidence is only partially explained by well-established risk factors related to hormones and reproduction. It has been suggested that exposure to organic solvents in the workplace may play a role in the etiology of breast cancer, but epidemiological studies on these occupational exposures in female breast cancer did not assess exposure to specific solvents and reported inconsistent results. Methods We examined the risk of breast cancer-related to lifetime exposure to organic solvents in a large population-based case-control study carried out in France between 2005 and 2008; 1230 women newly diagnosed for a breast cancer and 1315 population controls were included. A standardized questionnaire was administered during in-person interviews by trained interviewers to obtain information on socio-demographic characteristics, medical and family history, anthropometric measurements, reproductive history, tobacco and alcohol consumption, diet, and lifetime occupational history. All jobs held during occupational history were coded using the International Standard Classification of Occupations (ISCO 1968) and the Classification of Activities in the European Community (NACE 1991). Exposure to chlorinated (n = 4), petroleum (n = 5) and oxygenated (n = 5) solvents was assessed using a detailed job-exposure matrix (JEM) developed by the French National Agency for Public Health. Each job held was assigned indices of exposure probability, frequency and intensity. A Cumulative Exposure Score (CES) was calculated for each subject as the sum of the products of exposure probability, frequency and intensity, and duration for each job held over the entire occupational life. Odds ratio (ORs) and their 95% confidence intervals (95% CI) were estimated using unconditional logistic regression adjusting for potential confounders. Results The highest lifetime exposure prevalence was found for alcoholic solvents (41.8% of the cases and 41.4% of the controls); white spirit (8.3% of the cases and 10.2% of the controls); and trichloroethylene (10.7% of the cases and 11.8% of the controls). Compared to non-exposed subjects, women in the highest cumulative exposure quartile for alcoholic solvents had an OR of 1.17 (95% CI = 0.90–1.52). This OR increased to 1.61 (95% CI = 1.06–2.46) in premenopausal women. Exposure to ethylene glycol was also associated with an increased OR of 1.36 (95% CI = 0.93–1.97) in premenopausal women. No association was observed for other oxygenated solvents, petroleum solvents or chlorinated solvents. Conclusions These findings suggest a role of occupational exposure to oxygenated solvents, notably to alcohols, in the occurrence of breast cancer. Further studies conducted in cohorts of women with high prevalence of exposure to solvents are needed to confirm these results.

Night work and prostate cancer risk: results from the EPICAP Study

ObjectiveTo investigate the role of night work in prostate cancer based on data from the EPICAP Study.MethodsEPICAP is a French population-based case-control study including 818 incident prostate cancer cases and...

Time-dependent effect of intensity of smoking and of occupational exposure to asbestos on the risk of lung cancer: results from the ICARE case–control study

ObjectiveTo estimate the impact of intensity of both smoking and occupational exposure to asbestos on the risk of lung cancer throughout the whole exposure history.MethodsData on 2026 male cases and...

Occupational exposure to petroleum-based and oxygenated solvents and hypopharyngeal and laryngeal cancer in France: the ICARE study

BackgroundTo examine associations between occupational exposure to petroleum-based and oxygenated solvents and the risk of hypopharyngeal and laryngeal cancer.MethodsICARE is a large, frequency-matched population-based case-control study conducted in France. Lifetime occupational history, tobacco smoking and alcohol consumption were collected. Analyses were restricted to men and included 383 cases of hypopharyngeal cancer, 454 cases of laryngeal cancer, and 2780 controls. Job–exposure matrices were used to assess exposure to five petroleum-based solvents (benzene; gasoline; white spirits; diesel, fuels and kerosene; special petroleum products) and to five oxygenated solvents (alcohols; ketones and esters; ethylene glycol; diethyl ether; tetrahydrofuran). Odds ratios (ORs) adjusted for smoking, alcohol drinking and other potential confounders and 95% confidence intervals (CI) were estimated with unconditional logistic models.ResultsNo significant association was found between hypopharyngeal or laryngeal cancer risk and exposure to the solvents under study. Non-significantly elevated risks of hypopharyngeal cancer were found in men exposed to high cumulative levels of white spirits (OR = 1.46; 95% CI: 0.88–2.43) and tetrahydrofuran (OR = 2.63; 95CI%: 0.55–12.65), with some indication of a dose-response relationship (p for trend: 0.09 and 0.07 respectively).ConclusionThis study provides weak evidence for an association between hypopharyngeal cancer and exposure to white spirits and tetrahydrofuran, and overall does not suggest a substantial role of exposure to petroleum-based or oxygenated solvents in hypopharyngeal or laryngeal cancer risk.

Risk factors for salivary gland cancers in France: Results from a case-control study, the ICARE study

ObjectivesEpidemiological studies on the risk factors for salivary gland cancers (SGC) are rare, concern a small sample size, and show inconsistent results. The aim of the present work was to analyze several risk factors for SGC, using the data from the ICARE study, a multicenter, population-based case-control study. Materials and methodsData from 73 SGC cases and 3555 controls were collected using a standardized questionnaire on lifestyle habits, personal and family medical history, and lifetime occupational history. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regressions. ResultsTobacco use and alcohol consumption were not associated with the risk of SGC. A history of head and neck cancer or that of cervicofacial radiotherapy was associated with a higher risk of SGC (OR = 17.06, 95% CI: 4.34–67.05, and OR = 31.74, 2.48–405.25, respectively). Significantly increased risks were observed for some occupations: waiter (OR = 2.94, 1.11–7.78), charworker (OR = 3.02, 1.38–6.60), electrical and electronic equipment assembler (OR = 7.16, 2.02–25.38), plumber (OR = 3.95, 1.33–11.67), electric arc welder (OR = 6.15, 1.76–21.48), sheet-metal worker (OR = 2.89, 1.01–8.32), building painter (OR = 3.42, 1.01–11.49), and material handling equipment operator (OR = 5.05, 1.71–14.84). Results for industries were consistent with those observed for occupations. ConclusionOur results showed that a history of head and neck cancer, cervicofacial radiotherapy, and several occupations and industries, were associated with an increased risk of SGC. Further studies with larger sample sizes are indicated to confirm our results.

Association between shiftwork and the risk of colorectal cancer in females: a population-based case–control study

ObjectiveResearch indicates that shiftwork may be associated with increased risks of adverse health outcomes, including some cancers. However, the evidence of an association between shiftwork and colorectal cancer risk is...

Is There a Link between Occupational Silica or Asbestos Exposure and Kidney Cancer? A Case-Control Study in Canadian men

Background/Aim: Asbestos and crystalline silica are prevalent workplace exposures and are recognized human carcinogens. As few studies have investigated their associations with kidney cancer, we sought to address this gap using a Canadian case-control study. Methods: Incident cancer cases were identified by provincial cancer registries and self-reported questionnaires were used to obtain information on cancer risk factors and lifetime occupational history as part of the National Enhanced Cancer Surveillance System (NECSS). The NECSS is a population-based case-control study conducted from 1994-1997 in eight Canadian provinces. Occupational hygienists coded occupational histories for asbestos and silica exposure using concentration, frequency, and reliability, enabling the development of several exposure metrics. Logistic regression was used to estimate, separately by exposure, odds ratios (OR) and 95% confidence intervals. Models were adjusted for age, province, BMI, and cigarette smoking. Results: Complete occupational data were available for 652 cancer cases and 2,368 controls. Overall, 33% and 44% of workers were ever occupationally exposed to asbestos and silica, respectively. Obesity and older age were positively associated with kidney cancer, however smoking was not. Workers who had ever been exposed to asbestos were significantly more likely to have kidney cancer than those who were never exposed (OR 1.2, 95% CI 1.0 – 1.5). Ever-exposure to silica was not related to a significantly elevated risk of kidney cancer (OR 1.1, 95%CI 0.9 – 1.4). When examining duration of exposure as well as tertiles of cumulative asbestos exposure, calculated by multiplying relative frequency and concentration by duration, exposure was linked to an increased risk of kidney cancer, but only significantly so in the lowest tertile (OR 1.4, 1.0 – 1.9). In similar analyses for silica, no significant relationships were observed when comparing exposed to unexposed workers. Conclusions: We found evidence that occupational exposure to asbestos, but not silica, is positively associated with kidney cancer.

Case–control study to assess the association between colorectal cancer and selected occupational agents using INTEROCC job exposure matrix

BackgroundColorectal cancer is the third most prevalent cancer in the world and is twice as common in developed countries when compared with low-income and middle-income countries. Few occupational risk factors...

Anti-inflammatory drug use and progressive supranuclear palsy

BackgroundAnti-inflammatory drug use, particularly ibuprofen, has been associated with a lower risk of Parkinson's disease. Microglial activation and inflammatory cytokine expression have been shown to be pathological features of progressive supranuclear palsy. We examined the association between NSAID use and risk of PSP, disease severity and age at onset. MethodsThe ENGENE-PSP multicenter case-control study recruited incident PSP cases who met the NINDS-PSP Society diagnostic criteria and age-, sex- and race-matched controls primarily from the same geographical areas. All subjects underwent standardized interviews to obtain data on demographics, residential history, medication history and lifetime occupational history. NSAID use was specifically queried by telephone interview using a standardized questionnaire. ResultsInformation was obtained on anti-inflammatory drug exposure in 276 cases and 278 controls. No association was found between NSAID exposure and risk of PSP, age at onset or rate of change of UPDRS motor subscale, PSP Rating Scale or Mattis Dementia Rating Scale scores. This lack of association persisted when NSAID exposure was measured considering any NSAIDs, ibuprofen only, ASA only or non-ibuprofen, non-aspirin NSAIDs. ConclusionsThese results do not suggest an important association between NSAID use and PSP occurrence or expression. Despite the large size of our study, confidence intervals were wide. To rule out small associations, very large sample sizes will be required.