Occupational exposure to wood dust and risk of lung cancer: the ICARE study.

OBJECTIVES: In a previous analysis of data from a French population-based case-control study (the Investigation of occupational and environmental CAuses of REspiratory cancers (ICARE) study), 'having ever worked' in wood-related occupations was associated with excess lung cancer risk after adjusting for smoking but not for occupational factors. The present study aimed to investigate the relationship between lung cancer risk and wood dust exposure after adjusting for occupational exposures. METHODS: Data were obtained from 2276 cases and 2780 controls on smoking habits and lifelong occupational history, using a standardised questionnaire with a job-specific questionnaire for wood dust exposure. Logistic regression models were used to calculate ORs and 95% CIs adjusted for age, area of residence, tobacco smoking, the number of job periods and exposure to silica, asbestos and diesel motor exhaust (DME). RESULTS: No significant association was found between lung cancer and wood dust exposure after adjustment for smoking, asbestos, silica and DME exposures. The risk of lung cancer was slightly increased among those who were exposed to wood dust more than 10 years, and had over 40 years since the first exposure. CONCLUSION: Our findings do not provide a strong support to the hypothesis that wood dust exposure is a risk factor for lung cancer. This study showed the importance of taking into account smoking and occupational coexposures in studies on lung cancer and wood dust exposure. Further studies evaluating the level and frequency of exposure during various tasks in woodwork are needed.

Poor Perceived Health is Associated with Current use of Electronic Cigarette among Current and Former Smokers: Findings from the CONSTANCES Cohort.

BACKGROUND: Electronic cigarettes (e-cigarettes) have become increasingly popular, yet beyond social or technical features, the specific health-related reasons adults use e-cigarettes remain poorly understood. OBJECTIVE: To explore the cross-sectional associations between perceived health and current e-cigarette use in a large population-based cohort. METHODS: From the participants included in the French CONSTANCES cohort (a large general-purpose national population-based cohort) from 2015 to 2017, we included 18,300 ever tobacco smokers with data on their e-cigarette use. We used logistic regressions to estimate the associations between e-cigarette use and perceived health (global and respiratory), stratifying on participants' smoking status and adjusting for sociodemographic characteristics. To examine the role of objective health features (reported diagnoses and measured parameters during a health examination), we adjusted for prior history of respiratory and cardiovascular diseases, diabetes, cancer, spirometry, and blood pressure. Finally, we examined the effect of additionally adjusting for several health-related behaviors. RESULTS: Participants with poor perceived health (global and respiratory) were at greater risk of e-cigarette use. These associations remained unchanged after adjustment for objective health features and health-related behaviors (e.g., in current smokers, for global perceived health, an odds ratio of 1.10 [95% CI 1.03-1.16] per increase on an 8-point scale from very good to very poor). CONCLUSIONS: Our findings suggest that the more current and former smokers felt unhealthy, the more they tended to currently use e-cigarettes. People who regularly use e-cigarettes should obtain medical supervision that takes into account not only objective diagnoses and measurements but also perceived health. Counseling practices could include assessing perceived health status to reinforce motivation to quit smoking.

Occupational exposure to flour dust and the risk of head and neck cancer.

BACKGROUND: To investigate the association between head and neck squamous cell cancer (HNSCC) risk and occupational exposure to flour dust in women and men, using data from ICARE, a French population-based case-control study. METHODS: The analysis included 2053 cases of HNSCC and 3507 controls. Lifelong occupational history was collected. A job-exposure matrix was used to assess exposure to flour dust. Odds-ratios (ORs) and 95% confidence intervals (CI), adjusted for smoking, alcohol drinking, and asbestos exposure, were estimated with logistic regression models. RESULTS: Ever exposure to flour dust was associated with elevated ORs in women (OR = 2.15, 95%CI: 1.01 4.55) and in men (OR = 1.55, 95%CI: 1.11 2.17). In women, the risk increased with the probability, the duration, and the cumulative level of exposure. No dose-response relationships were observed in men. CONCLUSIONS: Although the results were less conclusive in men than in women, overall, these findings provide some support to the hypothesis of a role of flour dust in the occurrence of HNSCC.

Occupational exposure to organic solvents and risk of male breast cancer: a European multicenter case-control study.

Objectives The etiology of male breast cancer (MBC) is largely unknown but a causal role of exposure to organic solvents has been suggested. Previous studies on occupational risk factors of breast cancer were often restricted to women who are frequently exposed to lower levels and at a lower frequency than men. We investigated the association between MBC and occupational exposure to petroleum and oxygenated and chlorinated solvents in a multicenter case-control study of rare cancers in Europe. Methods The study included 104 MBC cases and 1901 controls. Detailed lifetime work history was obtained during interviews, together with sociodemographic characteristics, medical history and lifestyle factors. Occupational exposures to solvents were estimated from a job-exposure matrix. Odds ratios (OR) and their 95% confidence intervals (CI) were calculated using unconditional logistic regression models. Results Lifetime cumulative exposure to trichloroethylene >23.9 ppm years was associated with an increased MBC risk, compared to non-exposure [OR (95% CI): 2.1 (1.2-4.0); P trend <0.01). This increase in risk persisted when only exposures that occurred ≥10 years before diagnosis were considered. In addition, a possible role for benzene and ethylene glycol in MBC risk was suggested, but no exposure-response trend was observed. Conclusions These findings add to the evidence of an increased risk of breast cancer among men professionally exposed to trichloroethylene and possibly to benzene or ethylene glycol. Further studies should be conducted in populations with high level of exposure to confirm our results.

Occupational exposure to solvents and risk of head and neck cancer in women: a population-based case-control study in France.

OBJECTIVE: Our objective was to investigate the association between head and neck cancer and occupational exposure to chlorinated, oxygenated and petroleum solvents in women. METHODS: Investigation of occupational and environmental CAuses of REspiratory cancers (ICARE), a French population-based case-control study, included 296 squamous cell carcinomas of the head and neck (HNSCC) in women and 775 female controls. Lifelong occupational history was collected. Job-exposure matrices allowed to assess exposure to 5 chlorinated solvents (carbon tetrachloride; chloroform; methylene chloride; perchloroethylene; trichloroethylene), 5 petroleum solvents (benzene; special petroleum product; gasoline; white spirits and other light aromatic mixtures; diesel, fuels and kerosene) and 5 oxygenated solvents (alcohols; ketones and esters; ethylene glycol; diethyl ether; tetrahydrofuran). OR and 95% CIs, adjusted for smoking, alcohol drinking, age and geographical area, were estimated with logistic models. RESULTS: Elevated ORs were observed among women ever exposed to perchloroethylene (OR=2.97, 95% CI 1.05 to 8.45) and trichloroethylene (OR=2.15, 95% CI 1.21 to 3.81). These ORs increased with exposure duration (OR=3.75, 95% CI 0.64 to 21.9 and OR=4.44, 95% CI 1.56 to 12.6 for 10 years or more, respectively). No significantly increased risk of HNSCC was found for occupational exposure to the other chlorinated, petroleum or oxygenated solvents. CONCLUSIONS: These findings suggest that exposure to perchloroethylene or trichloroethylene may increase the risk of HNSCC in women. In our study, there is no clear evidence that the other studied solvents are risk factors for HNSCC.

Welding, a risk factor of lung cancer: the ICARE study.

OBJECTIVES: We investigated the relationship between lung cancer and occupational exposure to welding activity in ICARE, a population-based case-control study. METHODS: Analyses were restricted to men (2276 cases, 2780 controls). Welding exposure was assessed through detailed questionnaires, including lifelong occupational history. ORs were computed using unconditional logistic regression, adjusted for lifelong cigarette smoking and occupational exposure to asbestos. RESULTS: Among the regular welders, welding was associated with a risk of lung cancer (OR=1.7, 95% CI 1.1 to 2.5), which increased with the duration (OR=2.0, 95% CI 1.0 to 3.9 when duration >10 years), and was maximum 10-20 years since last welding. The risk was more pronounced in case of gas welding (OR=2.0, 95% CI 1.2 to 3.3), when the workpiece was covered by paint, grease, or other substances (OR=2.0, 95% CI 1.2 to 3.4) and when it was cleaned with chemical substances before welding. No statistically significant increase in lung cancer risk was observed among occasional welders. CONCLUSIONS: Although these results should be confirmed, we showed that type of welding and mode of workpiece preparation are important determinants of the lung cancer risk in regular welders.

The joint effect of asbestos exposure, tobacco smoking and alcohol drinking on laryngeal cancer risk: evidence from the French population-based case-control study, ICARE.

OBJECTIVE: The objective of the study was to investigate the joint effect of occupational exposure to asbestos, and tobacco and alcohol consumption, on the risk of laryngeal cancer among men. METHODS: We used data from a large population-based case-control study conducted in France. We estimated two-way and three-way interactions between asbestos exposure (never vs ever exposed), tobacco consumption (<20 vs. ≥20 pack-years) and alcohol consumption (<5 vs. ≥5 drinks per day). The interaction on an additive scale was assessed by estimating the relative excess risk due to interaction (RERI) and the attributable proportion due to interaction, and the interaction on a multiplicative scale was assessed by estimating the multiplicative interaction parameter (ψ). Multiplicative interactions were also assessed using fractional polynomials for alcohol drinking, tobacco smoking and asbestos exposure. RESULTS: When compared with light-to-moderate smokers and drinkers never exposed to asbestos, the increase in laryngeal cancer risk was smallest among light-to-moderate drinkers and smokers exposed to asbestos (OR=2.23 (1.08 to 4.60)), and highest among heavy smokers and drinkers ever exposed to asbestos (OR=69.39 (35.54 to 135.5)). We found an additive joint effect between asbestos exposure and alcohol consumption (RERI=4.75 (-4.29 to 11.12)), whereas we observed a more than additive joint effect between asbestos exposure and tobacco consumption (RERI=8.50 (0.71 to 23.81)), as well as between asbestos exposure, and tobacco and alcohol consumption (RERI=26.57 (11.52 to 67.88)). However, our results did not suggest any interaction on a multiplicative scale. CONCLUSIONS: Our results suggest that asbestos exposure, in combination with tobacco and alcohol exposure, accounted for a substantial number of laryngeal cancer cases. Our findings therefore highlight the need for prevention in activities, such as construction work, where exposure to asbestos-containing materials remains.

Population attributable risks of oral cavity cancer to behavioral and medical risk factors in France: results of a large population-based case-control study, the ICARE study.

BACKGROUND: Population attributable risks (PARs) are useful tool to estimate the burden of risk factors in cancer incidence. Few studies estimated the PARs of oral cavity cancer to tobacco smoking alone, alcohol drinking alone and their joint consumption but none performed analysis stratified by subsite, gender or age. Among the suspected risk factors of oral cavity cancer, only PAR to a family history of head and neck cancer was reported in two studies. The purpose of this study was to estimate in France the PARs of oral cavity cancer to several recognized and suspected risk factors, overall and by subsite, gender and age. METHODS: We analysed data from 689 oral cavity cancer cases and 3481 controls included in a population-based case-control study, the ICARE study. Unconditional logistic regression models were used to estimate odds ratios (ORs), PARs and 95% confidence intervals (95% CI). RESULTS: The PARs were 0.3% (95% CI -3.9%; +3.9%) for alcohol alone, 12.7% (6.9%-18.0%) for tobacco alone and 69.9% (64.4%-74.7%) for their joint consumption. PAR to combined alcohol and tobacco consumption was 74% (66.5%-79.9%) in men and 45.4% (32.7%-55.6%) in women. Among suspected risk factors, body mass index 2 years before the interview <25 kg.m(-2), never tea drinking and family history of head and neck cancer explained 35.3% (25.7%-43.6%), 30.3% (14.4%-43.3%) and 5.8% (0.6%-10.8%) of cancer burden, respectively. About 93% (88.3%-95.6%) of oral cavity cancers were explained by all risk factors, 94.3% (88.4%-97.2%) in men and only 74.1% (47.0%-87.3%) in women. CONCLUSION: Our study emphasizes the role of combined tobacco and alcohol consumption in the oral cavity cancer burden in France and gives an indication of the proportion of cases attributable to other risk factors. Most of oral cavity cancers are attributable to concurrent smoking and drinking and would be potentially preventable through smoking or drinking cessation. If the majority of cases are explained by recognized or suspected risk factors in men, a substantial number of cancers in women are probably due to still unexplored factors that remain to be clarified by future studies.

Occupational Exposure to Diesel Motor Exhaust and Lung Cancer: A Dose-Response Relationship Hidden by Asbestos Exposure Adjustment? The ICARE Study.

Background. In a French large population-based case-control study we investigated the dose-response relationship between lung cancer and occupational exposure to diesel motor exhaust (DME), taking into account asbestos exposure. Methods. Exposure to DME was assessed by questionnaire. Asbestos was taken into account through a global indicator of exposure to occupational carcinogens or by a specific JEM. Results. We found a crude dose response relationship with most of the indicators of DME exposure, including with the cumulative exposure index. All results were affected by adjustment for asbestos exposure. The dose response relationships between DME and lung cancer were observed among subjects never exposed to asbestos. Conclusions. Exposure to DME and to asbestos is frequently found among the same subjects, which may explain why dose-response relationships in previous studies that adjusted for asbestos exposure were inconsistent.

Occupational biomechanical exposure predicts low back pain in older age among men in the Gazel Cohort.

PURPOSE: Occupational biomechanical exposures are considered as risk factors for low back pain in the working population. It has also been suggested that their effects persist after retirement. Our objectives were to assess the role of past biomechanical occupational exposure on low back pain in early old age among male participants of the Gazel Cohort. METHODS: Low back pain for more than 30 days in the past 12 months (LBP30) was assessed in 1996 and 2006 using a French version of the Nordic questionnaire in a subsample of the Gazel Cohort. Logistic regression models were used to study associations between LBP30 in 2006 and past occupational biomechanical exposure, self-reported in 1996, taking into account personal and psychosocial work factors self-reported in 1996, and the date of retirement provided by the company. A multinomial model served to study persistent and new cases, according to LBP30 in 1996. RESULTS: We studied 1,520 men aged 58-67 in 2006, most of them retired. Low back pain for more than 30 days in the past 12 months reported in 2006 was related to occupational biomechanical exposure encountered many years earlier (OR 1.55, 95% CI 1.05-2.27 for 10-20 years of exposure to bending/twisting, OR 1.71, 95% CI 1.17-2.49 for >20 years). These associations appeared specific to low back pain for more than 30 days in the past 12 months which persisted between 1996 and 2006. CONCLUSION: These results suggest that occupational biomechanical exposure during active life has persistent effects among men in early old age, even for people who left the workforce. They point out the importance of preventive measures at work for better health later and appear relevant for policy-making decisions concerning age at retirement.

Occupation and head and neck cancer in women-Results of the ICARE study.

BACKGROUND: Few occupational studies have addressed head and neck cancer, and these studies have been predominantly conducted in men. Accordingly, our objective was to investigate the association between head and neck cancer and occupation in women. METHODS: ICARE, a French population-based case-control study, included 296 squamous cell carcinomas of the head and neck in women and 775 controls. Lifelong occupational history was collected. Odds ratios (ORs) and 95% confidence intervals (CI), adjusted for smoking, alcohol drinking and education level, were estimated for occupations and industries. RESULTS: An elevated OR was observed for working proprietors working for 10 years or more (OR = 3.83, 95% CI: 1.12-13.0) with a significant trend with duration of employment (P = 0.047). Elevated but non-significant ORs were observed for street vendors (OR = 3.76, 95% CI: 0.99-14.3, P for trend = 0.13), bakers (OR = 4.19, 95% CI: 0.63-27.9, P for trend = 0.06), and welders and flame cutters (OR = 2.18, 95% CI: 0.33-14.4, P for trend = 0.05). CONCLUSIONS: This exploratory study suggests a role of occupational exposures in the development of HN cancer in women. Further investigations of exposures to specific agents are needed.

Exposure to chlorinated solvents and lung cancer: results of the ICARE study.

OBJECTIVE: To investigate the role of occupational exposure to chlorinated solvents in lung cancer aetiology. METHODS: ICARE (Investigation of occupational and environmental CAuses of REspiratory cancers) is a French, multicentre, population-based, case-control study. Information on the lifelong work history of 2926 cases and 3555 controls was collected using standardised questionnaires. Occupational exposures were assessed using job-exposure matrices for five chlorinated solvents. Solvents were studied separately and in combinations. ORs were computed using unconditional logistic regression models adjusted for classic risk factors, including a history of cigarette smoking and exposure to asbestos. Adjustment for socioeconomic status (SES) was also made. RESULTS: After adjustment for exposure to asbestos, we observed a positive, statistically significant association with lung cancer for men and women exposed to a combination of perchloroethylene (PCE), trichloroethylene and dichloromethane (DCM). Further adjustment for SES slightly decreased this association. In contrast, no statistically significant associations were found for other solvent combinations. CONCLUSIONS: These results suggest that exposure to PCE may constitute a risk factor for lung cancer, especially among women, who seem to have a higher prevalence of exposure than men.

Family history of cancer, personal history of medical conditions and risk of oral cavity cancer in France: the ICARE study.

BACKGROUND: The aim of this study was to evaluate the role of family history of cancer and personal history of other medical conditions in the aetiology of the oral cavity cancer in France. METHODS: We used data from 689 cases of oral cavity squamous cell carcinoma and 3481 controls included in a population-based case-control study, the ICARE study. Odds-ratios (ORs) associated with family history of cancer and personal medical conditions and their 95% confidence intervals (95% CI) were estimated by unconditional logistic regression and were adjusted for age, gender, area of residence, education, body mass index, tobacco smoking and alcohol drinking. RESULTS: Personal history of oral candidiasis was related to a significantly increased risk of oral cavity cancer (OR 5.0, 95% CI 2.1-12.1). History of head and neck cancers among the first-degree relatives was associated with an OR of 1.9 (95% CI 1.2-2.8). The risk increased with the number of first-degree relatives with head and neck cancer. CONCLUSION: A family history of head and neck cancer is a marker of an increased risk of oral cavity cancer and should be taken into account to target prevention efforts and screening. Further studies are needed to clarify the association between oral cavity cancer and personal history of candidiasis.

Occupation and head and neck cancer risk in men: results from the ICARE study, a French population-based case-control study.

OBJECTIVE: To investigate the associations between occupations and head and neck (HN) cancer risk in men. METHODS: ICARE is a French population-based case-control study on HN cancer. Analyses included 1833 cases and 2747 controls. Complete occupational history was collected. Odds ratios (ORs) were estimated for occupations and industries ever held and according to duration of employment. RESULTS: Elevated ORs, increasing with duration of employment, were observed for several occupations, including cleaners (OR = 1.7; 95% confidence interval [CI], 1.0 to 2.8), launderers (OR = 6.8; CI, 1.3 to 34.4), firefighters (OR = 3.9; CI, 1.4 to 11.2), several agricultural occupations, welders (OR = 1.9; CI, 1.3 to 2.8), structural metal preparers and erectors (OR = 2.1; CI, 1.2 to 3.7), rubber workers (OR = 2.0; CI, 1.0 to 3.9), several construction occupations, and material-handling equipment operators (OR = 1.8; CI, 1.1 to 2.9). Analyses by industry corroborated these findings. CONCLUSIONS: These results confirmed the role of occupational exposures in HN cancer.

Occupational exposure to chlorinated and petroleum solvents and mycosis fungoides.

OBJECTIVE: To evaluate the potential association between occupational exposure to chlorinated and petroleum solvents and mycosis fungoides (MF). METHODS: A questionnaire on lifetime job history was administered to 100 patients diagnosed with MF and 2846 controls. Odds ratios (ORs) were calculated as the measure of the association between exposure to each specific solvent and MF. RESULTS: In the total sample and in men, cases and controls did not differ in relation to exposure to any of the solvents studied. In women, an association with MF was seen for the highest level of estimated exposure to perchloroethylene (OR = 11.38; 95% confidence interval: 1.04 to 124.85) and for exposure less than the median to kerosene/fuel/gasoil (OR = 8.53; 95% confidence interval: 1.11 to 65.62). CONCLUSIONS: These results do not provide conclusive evidence that exposure to solvents may increase risk of MF because they were not found in men.

Risk of lung cancer associated with occupational exposure to mineral wools: updating knowledge from a french population-based case-control study, the ICARE study.

OBJECTIVES: To assess the risk of lung cancer associated with exposure to mineral wools (MWs), while taking into account smoking, asbestos, and crystalline silica exposures. METHODS: The analyses were restricted to men (1350 cases and 1912 controls). Lifelong occupational history was collected. MWs and asbestos exposures were assessed, using task-exposure matrices and silica exposure, a job-exposure matrix. RESULTS: We observed consistent not-significant increased risks of lung cancer of the same order of magnitude among workers exposed to high levels of MWs (odds ratio, 1.4; 95% confidence interval: 0.9 to 2.2; for highest quartile of the Cumulative Exposure Index). CONCLUSIONS: These results do not allow to draw firm conclusion about a carcinogenic effect of MWs on the lung, but they cannot exclude it. Given the high number of potentially exposed workers, it will be necessary to replicate them in a future further removed from the asbestos ban.

Body mass index, body mass change, and risk of oral cavity cancer: results of a large population-based case-control study, the ICARE study.

OBJECTIVE: The association between body mass index (BMI) and the risk of oral cavity cancer, suggested by the few available studies, is controversial because of weight loss preceding cancer diagnosis and possible confounding by tobacco and alcohol consumption. The aim of this study was to evaluate in France, a high-incidence country, the association between the risk of oral cavity cancer and body mass index at interview, 2 years before the interview and at age 30, as well as BMI change. METHODS: We used data from a population-based case-control study, the Investigation of occupational and environmental CAuses of REspiratory cancers study, with personal interviews and standardized questionnaires including 689 cases of oral cavity squamous cell carcinoma and 3,481 controls. Odds ratios (ORs) and 95% confidence intervals (95% CI) were estimated by unconditional logistic regression and were adjusted for gender, age, area of residence, education, tobacco smoking, and alcohol drinking. RESULTS: ORs were increased in underweight subjects at interview (OR 6.25, 95% CI 3.74-10.45). No association with underweight 2 years before the interview and at age 30 was found. Overweight and obesity at interview, 2 years before the interview and at age 30 were associated with decreased ORs (ranging from 0.13 to 0.60). BMI gain greater than 5% between age 30 and 2 years before the interview was inversely associated with oral cavity cancer (OR 0.42, 95% CI 0.33-0.54). These associations were stronger in men, and in smokers and drinkers. CONCLUSION: These results add further support to the existence of a reduced risk of oral cavity cancer among overweight and obese people or among people who increased their BMI in adulthood. The underlying mechanisms remain to be clarified.

Tea and coffee consumption and risk of oral cavity cancer: results of a large population-based case-control study, the ICARE study.

BACKGROUND: Results on the relationship between coffee and tea drinking and the risk of oral cavity cancer are contrasted. The aim of this study was to evaluate the relation between coffee and tea drinking and the risk of oral cavity cancer in France, a high incidence area. MATERIAL AND METHODS: We conducted a population based case-control study with face-to-face interviews and standardized questionnaires (the ICARE study, Investigation of occupational and environmental causes of respiratory cancers). We used data from 689 cases of oral cavity squamous cell carcinoma and 3481 controls. Odds-ratios (ORs) and 95% confidence intervals (95% CI) associated with tea and coffee consumption (quantity, duration, cumulative consumption) were estimated by unconditional logistic regression with adjustment for age, gender, area of residence, education, body mass index, tobacco smoking and alcohol drinking. RESULTS: We observed inverse associations between oral cavity cancer and tea or coffee consumption (odds ratio, 0.39; 95% CI 0.21-0.70, for the highest quartile of tea consumption, and 0.60, 95% CI 0.34-1.05, for the highest quartile of coffee consumption). Exclusive tea or coffee consumption was associated with a reduced risk of oral cavity cancer and their joint effect was multiplicative. No differences in risk between men and women or between consumers of tobacco and alcohol and non-consumers were observed. The odds ratios related to the subsites usually included in the oropharynx (soft palate and base of the tongue) did not differ significantly from that observed for the other subsites of the oral cavity. CONCLUSIONS: Tea and coffee drinking may decrease the risk of oral cavity cancer through antioxidant components which play a role in the repair of cellular damages. These findings need further investigation in prospective studies and the underlying mechanisms in humans remain to be clarified.