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.

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.

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.

Coccomyxa actinabiotis sp. nov. (Trebouxiophyceae, Chlorophyta), a new green microalga living in the spent fuel cooling pool of a nuclear reactor.

Life can thrive in extreme environments where inhospitable conditions prevail. Organisms which resist, for example, acidity, pressure, low or high temperature, have been found in harsh environments. Most of them are bacteria and archaea. The bacterium Deinococcus radiodurans is considered to be a champion among all living organisms, surviving extreme ionizing radiation levels. We have discovered a new extremophile eukaryotic organism that possesses a resistance to ionizing radiations similar to that of D. radiodurans. This microorganism, an autotrophic freshwater green microalga, lives in a peculiar environment, namely the cooling pool of a nuclear reactor containing spent nuclear fuels, where it is continuously submitted to nutritive, metallic, and radiative stress. We investigated its morphology and its ultrastructure by light, fluorescence and electron microscopy as well as its biochemical properties. Its resistance to UV and gamma radiation was assessed. When submitted to different dose rates of the order of some tens of mGy · h-1 to several thousands of Gy · h-1 , the microalga revealed to be able to survive intense gamma-rays irradiation, up to 2,000 times the dose lethal to human. The nuclear genome region spanning the genes for small subunit ribosomal RNA-Internal Transcribed Spacer (ITS) 1-5.8S rRNA-ITS2-28S rRNA (beginning) was sequenced (4,065 bp). The phylogenetic position of the microalga was inferred from the 18S rRNA gene. All the revealed characteristics make the alga a new species of the genus Coccomyxa in the class Trebouxiophyceae, which we name Coccomyxa actinabiotis sp. nov.

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 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.

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.

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.

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.

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.

Body mass index and lung cancer risk: results from the ICARE study, a large, population-based case-control study.

BACKGROUND: The association between body mass index (BMI) and lung cancer is still disputed because of possible residual confounding by smoking and preclinical weight loss in case-control studies. We examined this association using data from the multicenter ICARE study in France, a large, population-based case-control study. METHODS: A total of 2,625 incident lung cancer cases and 3,381 controls were included. Weight was collected at interview, 2 years before the interview, and at age 30. Lifetime smoking exposure was calculated using the comprehensive smoking index (CSI). Adjusted odds ratios (aORs) and 95 % confidence intervals were estimated by unconditional logistic regression and controlled for age, area, education, CSI, occupational exposure, previous chronic bronchitis, and parental history of lung cancer. We also examined the role of weight change. Analyses were stratified by smoking status and sex. RESULTS: When compared with that of men with normal BMI 2 years before the interview, lung cancer aORs (95 % CI) among men with BMIs of <18.5, 25-29.9, 30-32.4, and ≥32.5 kg/m(2) were 2.7 (95 % CI 1.2-6.2), 0.9 (95 % CI 0.7-1.1), 0.8 (95 % CI 0.6-1.1), and 0.8 (95 % CI 0.6-1.0), respectively (p(trend) = 0.02). Results were more pronounced among current smokers and were similar in men and women. Weight gain over time was associated with a significant decreased risk of lung cancer. CONCLUSIONS: We found an inverse dose-dependent association between lung cancer risk and BMI 2 years prior to interview in current smokers. IMPACT STATEMENT: BMI might be an individual factor impacting the risk of lung cancer related to smoking's carcinogen-induced DNA damage.

Occupational exposures to asbestos, polycyclic aromatic hydrocarbons and solvents, and cancers of the oral cavity and pharynx: a quantitative literature review.

PURPOSE: The role of occupational risk factors in oral and pharyngeal cancer is not well known and is possibly underestimated. This quantitative review summarizes epidemiological findings on exposure to asbestos, polycyclic aromatic hydrocarbons and solvents, and cancers of the oral cavity and pharynx. METHODS: A systematic literature search was performed. We analyzed 63 publications: 8 from case-control studies and 55 from cohort studies. For agents with at least five available studies with homogenous exposure, a series of meta-analyses was conducted to provide quantitative pooled estimates of risks, using random effect models. RESULTS: Exposure to asbestos (meta-RR 1.25; 95% CI 1.10-1.42) and to polycyclic aromatic hydrocarbons (meta-RR 1.14; 95% CI 1.02-1.28) was found to be associated with oral and pharyngeal cancer risk. On the other hand, no association was found with exposure to solvents in general (meta-RR 0.98; 95% CI 0.77-1.23) but the strong heterogeneity between studies suggested differences in exposures. The small number of studies with homogeneous exposure did not allow meta-analyses for specific solvents. CONCLUSIONS: Future investigations should overcome common weaknesses of past studies, in terms of sample size, characterization of exposure, and classification of cancer sites.

Mutations in TP53 tumor suppressor gene in wood dust-related sinonasal cancer.

The causal role of work-related exposure to wood dust in the development of sinonasal cancer has long been established by numerous epidemiologic studies. To study molecular changes in these tumors, we analyzed TP53 gene mutations in 358 sinonasal cancer cases with or without occupational exposure to wood dust, using capillary electrophoresis single-strand conformation polymorphism analysis and direct sequencing. A significant association between wood-dust exposure and adenocarcinoma histology was observed [adjusted odds ratio (OR) 12.6, 95% confidence interval (CI), 5.0-31.6]. TP53 mutations occurred in all histologies, with an overall frequency of 77%. TP53 mutation positive status was most common in adenocarcinoma (OR 2.0, 95% CI, 1.1-3.7; compared with squamous cell carcinoma), and mutation positivity showed an overall, nonsignificant association with wood-dust exposure (OR 1.6, 95% CI, 0.8-3.1). Risk of TP53 mutation was significantly increased in association with duration (> or =24 years, OR 5.1, 95% CI, 1.5-17.1), average level (>2 mg/m(3); OR 3.6, 95% CI, 1.2-10.8) and cumulative level (> or =30 mg/m(3) x years; OR 3.5, 95% CI, 1.2-10.7) of wood-dust exposure; adjustment for formaldehyde affected the ORs only slightly. Smoking did not influence the occurrence of TP53 mutation; however, it was associated with multiple mutations (p = 0.03). As far as we are aware, this is the first study to demonstrate a high prevalence of TP53 mutation-positive cases in a large collection of sinonasal cancers with data on occupational exposure. Our results indicate that mutational mechanisms, in particular TP53 mutations, are associated with work-related exposure to wood dust in sinonasal cancer.

Hormonal exposures and the risk of uveal melanoma.

OBJECTIVES: Several studies suggest that hormonal mechanisms may be associated with the development of uveal melanoma. Therefore, the association between the risk of uveal melanoma and exposure to hormonal exposures was investigated in a case-control study from nine European countries. METHODS: Incident cases of uveal melanoma were frequency-matched to population and hospital controls by country, age, and sex. Female subjects were asked about their reproductive history, use of menopausal hormone replacement therapy and oral contraceptives. Among men, occupational handling of oils while working with transformers or capacitors which contain polychlorinated biphenyls (PCB) was solicited. Unconditional logistic regression analyses were calculated, adjusting for several potential confounders. Analyses were stratified by sex. RESULTS: Two hundred and ninety-three cases (165 men, 128 women) and 3,198 control subjects (2,121 men, 1,077 women) were interviewed. Among women, no associations were observed with hormonal status variables, intake of hormonal therapy or intake of oral contraceptives. Men showed an increased risk with occupational exposure to transformer/capacitor oils (OR = 2.74; Bonferroni-corrected 99.3% CI 1.07-7.02). However, these results were based on few exposed subjects only. CONCLUSION: The results of this study do not support the hypothesis of a hormonal influence in the carcinogenesis of uveal melanoma. Our finding of a potentially increased risk with PCB-containing oils requires further research.

The bibliographic impact of epidemiological studies: what can be learnt from citations?

OBJECTIVE: To document one dimension of the impact of an epidemiological study through citations in scientific journals. METHODS: Two sets of articles from studies performed in France were considered. They presented original results on occupational risk factors for low back pain and upper limb disorders. Citations of these articles were retrieved through the Web of Science and Google Scholar, and selected according to several criteria. Most citations present in the Web of Science were also retrieved from Google Scholar, except for the most recent articles. In the Web of Science, after exclusion of self-citations and duplicates, the total number of citations was 109 from 23 different countries for the low back pain articles, with 96 citations from 18 countries for upper limb disorders. A relatively large number of the citations belonged to clinical journals outside the fields of occupational health, ergonomics and public health. CONCLUSION: This study suggests that results dealing with occupational health disseminate into various fields of clinical research. However, this is only one dimension of the impact of a study.