Occupation and cancer – follow-up of 15 million people in five Nordic countries

Indirect adjustment of tobacco smoking in occupational studies of lung cancer: A systematic review of the available methods and their applications

Tobacco smoking is an important risk factor and potentially a major confounding factor in occupational lung cancer studies. However, as individual information on tobacco smoking is often not available, indirect adjustment methods may be used to account for potential confounding from smoking. Therefore, we aimed at providing an overview of the available indirect adjustment methods for smoking in studies of occupational exposures and lung cancer risk. We conducted a systematic search of relevant studies that applied statistical methods for indirect adjustment of tobacco smoking and were published between 1-Jan-2000 and 2-Apr-2025 to capture developments in recent decades. Studies were retrieved from Embase, MEDLINE, and Web of Science. Fifteen studies fulfilled our inclusion criteria and were included. We grouped the studies into four methods of indirect smoking adjustment: (1) without distributions for adjusted data; (2) distributions for adjusted data; (3) negative control outcomes; (4) factor analysis models. For studies with an external comparison group, percentage change in estimates from before to after indirect adjustment ranged -36.1 %_to_+ 17.3 %, while the corresponding range for those with internal comparison was -16.2 %_to_+ 47.8 %. The choice of indirect adjustment method depends on the use of reference group (external vs. internal) and the data available. Adjustment methods 1 and 2 use partial cohort data or ancillary data from other similar workers and may be preferable over methods 3 and 4, if such data are available. Methods 3 and 4 may be well suited if such data are lacking but have stronger assumptions.

Welding Fumes Exposure and the Risk of Head and Neck and Gastrointestinal Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

The association between welding fumes and cancers other than lung cancer remains undefined. We conducted a systematic review and meta-analysis on occupational exposure to welding fumes and the risk of head and neck cancer (HN, comprising oral, pharynx, and larynx) and gastrointestinal cancer (GI, comprising esophagus, stomach, colorectal, liver, and pancreas).

METHODS

A systematic search was performed in PubMed, Scopus, and Embase using PRISMA guidelines. Cohort studies on occupational exposure to welding fumes were identified. Study quality was assessed through the CASP score. Data were analyzed in random-effects models to calculate the relative risks (RR) and 95% confidence intervals (CI) of HN and GI cancer overall and stratified by cancer site.

RESULTS

Seven independent studies with data on oral, pharynx, larynx, esophagus, stomach, colorectal, liver, or pancreas cancer were identified. We observed the following associations: HN RR=1.10 (95% CI 1.00-1.22); GI RR= 1.03 (95% CI 0.97-1.10); oral and pharynx RR=1.06 (95%, CI 0.93-1.20, eleven risk estimates); larynx RR=1.17 (95%, CI 1.01-1.37, nine risk estimates); esophagus RR=0.98 (95%, CI 0.83-1.15, three risk estimates); stomach RR= 1.10 (95%, CI 1.02-1.19, five risk estimates); colorectal RR=0.99 (95%, CI 0.85-1.15, seven risk estimates); liver RR=1.23 (95%, CI 0.79-1.90, five risk estimates); and pancreas cancer RR=1.05 (95%, CI 0.94-1.16, three risk estimates).

CONCLUSIONS

We observed an association between occupational exposure to welding fumes and larynx and stomach cancer. No association was found for other HN or GI cancers. Our study stresses the need to investigate the risk of cancers other than lung following occupational exposure to welding fumes.

Cancer incidence and cause-specific mortality in 2663 male submariners with service in the Royal Norwegian Navy between 1942 and 2005: a registry-based cohort study

OBJECTIVES

A previous cohort study of male Norwegian Navy submariners showed higher overall cancer incidence and lower all-cause mortality than the general Norwegian population. We have extended the follow-up and show more precise estimates through seven decades.

DESIGN

Historical cohort study using outcome data from Norwegian cancer incidence and cause-of-death registries.

SETTING

Linkage with the outcome registries was performed by means of unique national identification numbers given to all Norwegian citizens.

PARTICIPANTS

2663 military men who ever served aboard a Navy submarine between 1942 and 2005.

OUTCOME MEASURES

Standardised incidence ratios for cancer and mortality ratios were calculated from national period-specific, gender-specific and age-specific rates. Poisson regression was used to compare cancer incidence in groups with different length of submarine service (>2 years vs ≤2 years).

RESULTS

The overall cancer incidence was 15% higher than expected from the national rates, with colon, lung, skin (melanoma and non-melanoma) and urinary tract contributing 90% of the excess number of cases. Most of the excess was confined to those with shorter-time service, who also showed elevated risk of alcohol-related cancers. Excess non-melanoma skin cancer was most clearly seen among submariners with >2 years of service. Mortality from all causes combined was lower among submariners than in the general population, due to a markedly low mortality from non-neoplastic diseases and external causes.

CONCLUSIONS

Increased risk of non-melanoma skin cancer was found among submariners with long-term service, and skin exposure to carcinogens in petroleum products was hypothesised as an explanation. Less support for occupational risks was found for other cancers, although the lack of specific exposure data and limited statistical power reduced the possibility of identifying such associations. A 'healthy soldier effect' appeared in the mortality data, mainly restricted to low mortality from non-neoplastic diseases and external causes.

Socioeconomic position and risk of cervical cancer in the Nordic countries: Results from the Nordic Occupational Cancer Study

The Nordic countries benefited from declines in cervical cancer incidence rates due to the implementation of screening programmes. However, it is unclear whether all social groups have equally benefited from these preventive services. We provide an assessment of the temporal trends in cervical cancer incidence by socioeconomic position (SEP) in Denmark, Norway, Finland and Sweden, using data from the Nordic Occupational Cancer Study. Truncated age-standardized incidence rates and 95% confidence intervals (CI) of cervical cancer per 100,000 person-years were computed for women aged 50-69 by SEP and country within the period 1961-2005. We used Poisson regression models to compute relative risks (RRs) and 95% CIs of cervical cancer across SEP, pooling data for the three most recent 5-year periods (except for Denmark 1991-1995 and Norway 1991-2003). Throughout the study period, declines in the rates of cervical cancer were observed among all SEP groups. Lower SEP rates, which started from higher values, declined faster than those for higher SEP. At the conclusion of the study period, we still observed a social gradient, with higher rates seen in lower SEP women. Farmers had the lowest risk in all four countries. The RRs for lowest versus highest SEP ranged from 1.33 (95% CI 1.05-1.69) in Sweden to 1.76 (95% CI 1.13-2.85) in Denmark, with a pooled RR of 1.41 (95% CI 1.22-1.64). Lower SEP women still face the highest risks, indicating a need for continued efforts to provide equitable access to preventive services.

Is work burden associated with postmenopausal breast cancer? A population-based 25-year follow-up

OBJECTIVE

To study the association between breast cancer and work burden over 25 years.

METHODS

The study was based on the Kuopio Osteoporosis Risk Factor and Prevention (OSTPRE) cohort (n = 14,220) and included women who had answered the questionnaire from the year 1994 and had no previous breast cancer. Breast cancer cases were recorded from the Finnish Cancer Registry during the study period: from 1st June 1994 till December 31, 2019. Using questionnaires, we collected information on work burden, body mass index (BMI), menopausal hormone therapy (MHT), alcohol consumption, parity, and family history of breast cancer. Work burden was categorized as low or high. Variables were used both in the univariate and multivariate Cox regression analyses to explore their associations with breast cancer.

RESULTS

Altogether 825 women (6.9%) were diagnosed with breast cancer during the study period with a mean follow-up of 13.3 ± 7.2 years. Women with breast cancer were compared to those without breast cancer during the follow-up period (n = 11,117). A low work burden was associated with a 1.3-fold higher incidence of breast cancer (95% confidence interval 1.2-1.6) than a high work burden. Low work burden was associated with an increased breast cancer risk.

CONCLUSION

Low work burden is associated with elevated postmenopausal breast cancer risk in the 25-year follow-up period.

Management and Collection of Occupational Data for Health (ODH) in National Public Health Statistics: Evaluation and Recommendations for Korea

Background

The aims of this study are to examine how occupation-related data and information for health (ODH) are collected and managed from census-based surveys and potential occupational illness and injuries (POIS) statistics, and to propose a national strategy for the systematic collection, analysis, and management of ODH by building on the Korean Standard Classification of Occupation (KSCO) and using a job exposure matrix (JEM).

Methods

The status of the collection and management of ODH registered as national statistics, drawn not only from the census-based general population and workforce, but also from POIS statistics was reviewed and evaluated.

Results

ODH from the Republic of Korea's Census of Population and Labor Force are collected and classified according to the KSCO. In contrast, national statistics on POIS are not systematically collected for KSCO coding, reflecting the lack of an KSCO and related guidelines on how to collect ODH. Key frameworks for the construction of both an KSCO and a reference JEM for public health surveillance are proposed.

Conclusions

Further research is needed to develop a national system for collecting and managing ODH, which will ultimately contribute to the use of a national KSCO and the construction of JEM for public health surveillance.

Occupational Diesel Exposure and Brain Tumors: A Systematic Review and Meta-Analysis

Diesel exhaust (DE) is recognized as a carcinogen for the lungs, although evidence linking it to adult brain tumors is limited. We aimed to systematically review the evidence regarding the association between occupational DE exposure and adult brain and other central nervous system (CNS) tumors. A systematic literature review was conducted to identify cohort studies on occupational DE exposure and the risk of adult cancers other than lung cancer. We meta-analyzed relative risks (RRs) and 95% confidence intervals (CIs) for brain or CNS tumors using the DerSimonian and Laird random-effects model. Fourteen studies were included in the meta-analysis. The results showed no in-creased risk of brain or CNS tumors among workers exposed to DE (RR: 0.99; 95% CI: 0.91, 1.07). Findings were consistent when analyzing studies based on incidence (RR: 0.96; 95% CI: 0.90, 1.03; six studies) and mortality (RR: 1.09; 95% CI: 0.87, 1.37; nine studies) separately, as well as in subgroup analyses based on sex, publication year, geographic region, and study quality score. No evidence of publication bias was found (p=0.244). The findings of our meta-analysis suggest that occupational DE exposure is not associated with adult brain or CNS tumors. Given the limitations of the included studies, these results should be interpreted with caution.

Cancer mortality and sectors of employment: a cohort study in Italy

BACKGROUND

Cancer is a multifactorial disease. The large impact of occupational exposure on the burden of cancer continues to be a paramount public health concern that deserves more attention. The study aims to evaluate cancer-specific mortality risk in relation to sectors of employment.

METHODS

We used a cohort from the Rome Longitudinal Study (ROL) and linked it with the National Social Insurance Agency (INPS) database to obtain working histories. We considered the longest duration of employment in a sector as a proxy of exposure, and insurance activities as the reference category. A Cox regression adjusted model was used to examine the associations between cancer-specific causes of death and the sector of employment in men and women. A similar analysis was performed considering the length of employment (≤ 10 years versus ≥ 10 years).

RESULTS

The study population comprised 910,559 (52% of the total population of the cohort after linkage with INPS) 30 + yr employees (53% men and 47% women) followed for a total period of approximately 7 million years. The outcomes confirmed some well-known associations (e.g. lung and pleura in construction, pleura in paper and printing, and lung in wood and leather) and suggested possible high-risk sectors that have not yet been thoroughly investigated. In men we observed an increased mortality risk for stomach cancer in the printing and paper industry (HR = 1.69, 95% CI:1.11-2.57) as well as for stomach and lung cancer in cleaning activities (HR = 1.98, 95% CI:1.13-3.49 and HR = 1.55, 95% CI:1.22-1.98, respectively). Among women, there was an elevated mortality risk in the cleaning industry for all malignant cancers (HR = 1.15, 95% CI:1.03-1.29), liver cancer (HR = 1.94, 95% CI:1.08-3.48) and cancer of the lympho-hematopoietic tissue (HR = 1.65, 95% CI:1.09-2.50).

CONCLUSIONS

The results showed an increased risk of cancer death in some traditional industrial sectors compared to the reference category of insurance activities such as construction and wood and leather products and limited evidence in sectors like cleaning, accommodation and food services and hairdressing. The adopted method proved to be effective in monitoring occupational risks and activating proper prevention initiatives and further insights.

Global, regional and national burden of lung cancer attributable to occupational carcinogens, 1990-2019: A study of trends, inequalities and predictions based on GBD 2019

BACKGROUND

Lung cancer, a leading cause of cancer-related mortality, is significantly influenced by occupational carcinogens. This study aimed to assess and predict global, regional and national trends of lung cancer burden attributable to occupational carcinogens.

METHODS

Data on the lung cancer burden attributable to nine occupational carcinogens were obtained from the Global Burden of Disease Study 2019. Regions were categorized by the Socio-Demographic Index (SDI). Descriptive statistics, Joinpoint regression, and Age-Period-Cohort (APC) models were employed to analyze trends in mortality and Disability-Adjusted Life Years (DALYs). Using the Slope Index of Inequality and Concentration Index, health inequalities were quantified. The ARIMA-LSTM model was developed to predict the burden from 2020 to 2030.

RESULTS

From 1990-2019, lung cancer deaths and DALYs due to occupational carcinogens increased. Global age-standardized mortality (ASMR) and DALY (ASDR) rates declined, while middle and lower SDI regions increased. Joinpoint regression and APC analysis revealed that the local drift, period, and cohort effects exhibited increasingly unfavorable trends in lower SDI regions, while they were decreasing trends in higher SDI regions. Conversely, age effects increased similarly across all SDI regions. Health inequalities worsened over time. The ARIMA-LSTM model demonstrated global ASMR and ASDR would decrease, while low-middle and low SDI regions were expected to experience substantial increases from 2020 to 2030.

CONCLUSION

Health inequality of lung cancer burden attributable to occupational carcinogens remained a critical concern, underscoring the urgent need for targeted occupational health policies for low and low-middle SDI regions.

Leveraging Administrative Health Databases to Address Health Challenges in Farming Populations: Scoping Review and Bibliometric Analysis (1975-2024)

BACKGROUND

Although agricultural health has gained importance, to date, much of the existing research relies on traditional epidemiological approaches that often face limitations related to sample size, geographic scope, temporal coverage, and the range of health events examined. To address these challenges, a complementary approach involves leveraging and reusing data beyond its original purpose. Administrative health databases (AHDs) are increasingly reused in population-based research and digital public health, especially for populations such as farmers, who face distinct environmental risks.

OBJECTIVE

We aimed to explore the reuse of AHDs in addressing health issues within farming populations by summarizing the current landscape of AHD-based research and identifying key areas of interest, research gaps, and unmet needs.

METHODS

We conducted a scoping review and bibliometric analysis using PubMed and Web of Science. Building upon previous reviews of AHD-based public health research, we conducted a comprehensive literature search using 72 terms related to the farming population and AHDs. To identify research hot spots, directions, and gaps, we used keyword frequency, co-occurrence, and thematic mapping. We also explored the bibliometric profile of the farming exposome by mapping keyword co-occurrences between environmental factors and health outcomes.

RESULTS

Between 1975 and April 2024, 296 publications across 118 journals, predominantly from high-income countries, were identified. Nearly one-third of these publications were associated with well-established cohorts, such as Agriculture and Cancer and Agricultural Health Study. The most frequently used AHDs included disease registers (158/296, 53.4%), electronic health records (124/296, 41.9%), insurance claims (106/296, 35.8%), population registers (95/296, 32.1%), and hospital discharge databases (41/296, 13.9%). Fifty (16.9%) of 296 studies involved >1 million participants. Although a broad range of exposure proxies were used, most studies (254/296, 85.8%) relied on broad proxies, which failed to capture the specifics of farming tasks. Research on the farming exposome remains underexplored, with a predominant focus on the specific external exposome, particularly pesticide exposure. A limited range of health events have been examined, primarily cancer, mortality, and injuries.

CONCLUSIONS

The increasing use of AHDs holds major potential to advance public health research within farming populations. However, substantial research gaps persist, particularly in low-income regions and among underrepresented farming subgroups, such as women, children, and contingent workers. Emerging issues, including exposure to per- and polyfluoroalkyl substances, biological agents, microbiome, microplastics, and climate change, warrant further research. Major gaps also persist in understanding various health conditions, including cardiovascular, reproductive, ocular, sleep-related, age-related, and autoimmune diseases. Addressing these overlooked areas is essential for comprehending the health risks faced by farming communities and guiding public health policies. Within this context, promoting AHD-based research, in conjunction with other digital data sources (eg, mobile health, social health data, and wearables) and artificial intelligence approaches, represents a promising avenue for future exploration.

Incidence rates of soft tissue sarcoma among U.S. military servicemen: Comparison with the rates in the general U.S. population

BACKGROUND

Soft tissue sarcoma (STS) is one of the most frequently diagnosed cancers among men younger than age 30 years and a leading cause of cancer death in men younger than age 40 years. The military may be more exposed to STS risk factors and have generally better health and health care access than the general population, which may relate to lower cancer risk and/or early detection. This study compared STS incidence between servicemen and men in the general U.S.

POPULATION

METHODS

Data were from the Department of Defense's Automated Central Tumor Registry (ACTUR) and the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program. Subjects were active-duty servicemen in ACTUR and men in SEER aged 18-59 years diagnosed with STS from 1990 to 2013. Age-adjusted rates, incidence rate ratios (IRR), and 95% CIs were calculated.

RESULTS

STS incidence rates were lower in ACTUR than SEER overall (IRR = 0.86 [0.78-0.93]), for 18- to 39-year-old men (IRR = 0.78 [0.70-0.86]), by race (White: IRR = 0.85 [0.77-0.95]; Black: IRR = 0.77 [0.63-0.94]), for sites other than skin/connective/soft tissue (IRR = 0.49 [0.37-0.63]), other specified histologies (IRR = 0.84 [0.71-0.98]), and unspecified histology (IRR = 0.57 [0.38-0.82]). Rates were lower in ACTUR for regional (IRR = 0.37 [0.28-0.47]) and distant metastases (IRR = 0.58 [0.43-0.76]), even when race and age stratified. However, rates were higher in ACTUR for 40- to 59-year-old men (IRR = 1.25 [1.04-1.48]) and localized tumors (IRR = 1.16 [1.04-1.29]).

CONCLUSION

Lower STS rates among servicemen may relate to better health and early detection and treatment of STS-associated conditions within the military health system, which provides universal care. Higher rates among 40- to 59-year-old servicemen may result from greater cumulative military-related exposures.

Laryngeal Cancer in Women: Unveiling Gender-Specific Risk Factors, Treatment Challenges, and Survival Disparities

Laryngeal cancer is one of the main causes of morbidity and mortality worldwide, with a significantly higher prevalence among men than women. However, the incidence, clinical characteristics, and specific treatment of laryngeal cancer in women have often been overlooked by research. This review aims to examine gender differences in incidence, risk factors, hormonal mechanisms, survival, and therapeutic approaches for laryngeal cancer in women. Although smoking and alcohol remain the main risk factors, evidence suggests that women may be more vulnerable to the harmful effects of these behaviors, with a relative higher risk than men. In addition, hormonal factors such as estrogen may influence women's susceptibility to laryngeal cancer, accelerating tumor growth and complicating treatment. Differences in treatment between the sexes, with women tending to receive less intensive treatment than men, is another crucial aspect that needs more attention. This article also analyses the disparities in survival, highlighting that women often have a better prognosis, although this trend varies according to demographic characteristics and the health system. The increasing incidence of laryngeal cancer in women requires increased research to fully understand risk factors and underlying biological mechanisms in order to develop more personalized treatments and optimize clinical outcomes for patients.

Night shift work and prostate cancer: a large cohort study from UK Biobank and Mendelian randomisation study

OBJECTIVE

The global concern regarding the health implications of night shift work has escalated. Nevertheless, variations exist in the observed association between night shift work and prostate cancer (PCa). This study aims to systematically explore the association between night shift work and the risk of PCa.

DESIGN

Cohort study and Mendelian randomisation (MR) study were used.

SETTING

Cohort study data was from the UK Biobank (UKB). MR study using data was from the Finngen study and UKB through the Integrative Epidemiology Unit (IEU) Open Genome-Wide Association Study Project.

PARTICIPANTS

Participants without prior PCa in paid employment or self-employment were include in the current work schedule cohort, participants without PCa who provided employment history formed the lifetime night shift work cohort.

MAIN OUTCOME MEASURES

The outcome, incident PCa, was obtained from cancer register through linkage to national cancer databases. National cancer registries centralised information received from separate regional cancer centres around the UK.

RESULTS

A total of 130 853 participants were included in the current work schedule cohort, while the lifetime night shift work cohort comprised 49 511 participants. Over a median follow-up duration of 13.9 years, the current work schedule cohort witnessed 4993 incident cases of PCa, while the lifetime night shift work cohort recorded 2022 PCa cases. In the analysis of the current work schedule, final model showed that no significant association was found between shift work and PCa risk, whether it involved shift but no night shifts (HR 0.96, 95% CI 0.85 to 1.08), some night shifts (HR 1.16, 95% CI 0.99 to 1.33) and usual night shifts (HR 1.01, 95% CI 0.85 to 1.19). In the analysis of the average frequency of night shift work, final model showed no significant impact of different night shift frequencies (<3/month: HR 0.97, 95% CI 0.73 to 1.29; 3-8/month: HR 0.99, 95% CI 0.83 to 1.19; >8/month: HR 0.89, 95% CI 0.73 to 1.07) on the risk of PCa. No significant association was found for either <10 years (HR 0.89, 95% CI 0.72 to 1.09) or ≥10 years (HR 1.00, 95% CI 0.86 to 1.16) of night shift work. Subsequent subgroup and sensitivity analyses demonstrated consistent results without significant alterations. Furthermore, in the two-sample MR analysis, no statistically significant causal relationship was identified between night shift work and the incidence of PCa.

CONCLUSION

In both the cohort studies and MR analysis, our investigation did not find any association between night shift work and PCa.

Literacy in the Scope of Radiation Protection for Healthcare Professionals Exposed to Ionizing Radiation: A Systematic Review

Background: The use of radiation is important in different medical procedures, and to ensure a high level of good medical practice, radiation protection (RP) should be seen as a very important subject. This review shows information about the knowledge in the scope of radiation protection among healthcare professionals exposed to ionizing radiation. There are not many studies that evaluate the radiation exposure of healthcare professionals. Methods: A systematic search was performed, using PRISMA guidelines, in Pubmed and Scopus databases and manually to identify relevant articles to answer the PICOS question, "Is there an adequate level of literacy in the scope of radiation protection among healthcare professionals exposed to ionizing radiation?". This systematic review included cross-sectional studies with the following inclusion criteria: (i) in Portuguese, Spanish, or English; (ii) about literacy in the scope of radiation protection; (iii) published between 2017 and 2024; and (iv) participants must be dentists, radiographers, doctors, and nurses. The JBI critical assessment tool was used to assess the risk of bias. Results: The search identified 566 potentially relevant references, which, after applying inclusion/exclusion criteria, resulted in 12 articles. Studies found that the overall knowledge of these healthcare workers was unsatisfactory, and a lack of knowledge in radiation protection negatively affects health services' quality. Training is essential and must emphasize how radiation exposure can be minimized, safeguarding health professionals' trust and sense of security. Results showed that more years of experience make workers more attentive to protection measures, suggesting that training strategies focused on basic radiological risks and radiation safety are needed. Conclusions: Key findings recommend implementing a standardized national training program on the basic principles and safety of ionizing radiation for all healthcare professionals.

Environmental Risk Factors for Gallbladder Cancer: Field-Wide Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Cholelithiasis is the most well-recognized risk factor for gallbladder cancer (GBC), the predominant biliary-tract malignancy; however, credibility on other modifiable exposures remains uncertain. We performed a field-wide systematic review and meta-analysis on environmental factors associated with GBC.

METHODS

We systematically searched Medline/PubMed and Embase up to May 8, 2023, to identify randomized and nonrandomized studies examining environmental factors for GBC. We conducted random-effects meta-analyses focusing on longitudinal studies. Evidence from case-control studies was considered complementary. Evidence credibility was graded by prespecified criteria including the random-effects estimate, 95% confidence interval (CI), P value, statistical heterogeneity, small-study effects, and robustness to unmeasured confounding.

RESULTS

We identified 215 eligible primary studies and performed 350 meta-analyses across 7 domains: lifestyle, reproductive, metabolic, dietary, infections, interventions, and contaminants and occupational exposures. Based on longitudinal evidence, body mass index (relative risk [RR] per 5-unit increase, 1.27; 95% CI, 1.21‒1.33), hip circumference (RR per 5-cm increase, 1.16; 95% CI, 1.11‒1.22), infection of bile ducts (RR, 31.7; 95% CI, 24.8-40.6), high parity (RR, 1.48; 95% CI, 1.30‒1.68), obesity (RR, 1.70; 95% CI, 1.44‒2.01), overweight (RR, 1.28; 95% CI, 1.14‒1.43), waist circumference (RR per 5-cm increase, 1.14; 95% CI, 1.10‒1.18), and waist-to-height ratio (RR per 0.1 increase, 1.49; 95% CI, 1.36‒1.64) were robustly associated with increased GBC risk, whereas high education (RR, 0.63; 95% CI, 0.49‒0.82) was associated with reduced risk (moderate-to-high credibility). Another 39 significant associations showed lower credibility, including different exposure scenarios of tobacco smoking, alcohol consumption, and insufficient physical activity.

CONCLUSIONS

This study offers a detailed appraisal and mapping of the evidence on modifiable factors for GBC. Further high-quality prospective studies are essential to validate emerging associations and inform preventive strategies in high-incidence areas. (Systematic review registration: CRD42023434673.).

Analysis of the Stockholm Public Health Cohort: Exploring How Ultraviolet Radiation and Other Factors Associate with Skin Cancer

Objective

The primary aims of the study were to (1) explore the association of skin cancer and four ultraviolet radiation (UVR) indicators (sunbed use, healthcare data on diagnosed melanocytic nevi (MN) and actinic keratosis (AK), and latitude of birthplace), and (2) find factors other than UVR that could explain the increasing trend in incidence of skin cancers, including basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and cutaneous malignant melanoma (CMM).

Methods

This population-based cohort study used self-reported questionnaire data from the Stockholm Public Health Cohort, encompassing 103 questions, merged with data from Swedish national registers. The study population included almost 35,000 Swedish-born people aged 30-66 years in 2014. Binomial logistic regression was employed for analysis. A forward stepwise regression was applied to select significant risk factors among all the factors included. We tentatively tested >30 variables separately for any relationship with each of the three skin cancers. A 5% level of significance was applied. Melanoma in situ and SCC in situ were excluded.

Results

The four UVR-related factors (sunbed use, being diagnosed with AK or MN, birthplace latitude) had a significant association with at least one of the three skin cancers that remained after adjustment including behavioural, social, hereditary, and medical factors. Sunbed use >10 times before age 30 years was related to all three skin cancers; SCC adjusted odds ratio (aOR) 1.66, 95% confidence interval (CI) 1.12-2.47, CMM (aOR 1.57, 95% CI 1.11-2.22), and the clearest dose-response association with BCC (aOR 1.74, 95% CI 1.46-2.06). None of the examined lifestyle factors, except physical activity, had any significant associations with UVR indicators or skin cancer.

Conclusion

We did not find any preventable explanatory cause other than UVR exposure for the increasing incidence of skin cancers. This result remained when adjusting for an array of possible confounders including behavioural, social, hereditary, and medical factors.

Meta-Analysis of the Relationship Between Occupational/Environmental Exposure to Wood Dust and Laryngeal Cancer

OBJECTIVE

Wood dust is a human carcinogen. However, studies examining the relationship between wood dust exposure and laryngeal cancer have yielded inconsistent findings. Therefore, we systematically reviewed relevant studies examining the relationship between wood dust exposure and laryngeal cancer development, followed by a meta-analysis.

METHODS

Publications in the following databases were searched: PubMed, Medline, Embase, Cochrane Library, and China National Knowledge Infrastructure (CNKI). The Newcastle-Ottawa scale was used to evaluate the study quality. A random-effects model was used for the meta-analysis.

RESULTS

Eighteen case-control studies and one cohort study, involving a total of 4426 patients with laryngeal cancer and 319,129 control participants, were identified. The association between occupational/environmental exposure to wood dust and laryngeal cancer, if any, was unclear (adjusted combined OR: 1.11; 95% CI: 0.94-1.31). However, subgroup analyses according to the number of cases, geographic region, publication year, and follow-up duration revealed correlations between wood dust exposure correlated and laryngeal cancer, as follows: number of cases > 200 (OR: 1.14; 95% CI: 1.01-1.25 [n = 10]); studies conducted in the US (OR: 1.21; 95% CI: 1.07-1.37 [n = 5]); follow-up time > 5 years (OR: 1.19; 95% CI: 1.07-1.32 [n = 10]); and publication after the year 2000 (OR: 1.15; 95% CI: 1.04-1.28 [n = 8]). A high heterogeneity in the results was observed (I2 = 42.5%, p = 0.024). The results were stable, and no publication bias existed, according to sensitivity analysis.

CONCLUSIONS

This meta-analysis suggests that wood dust exposure is associated with laryngeal cancer. Additional large-scale studies are warranted to clarify the relationship between wood dust exposure and laryngeal cancer.

Gastrointestinal cancer and occupational diesel exhaust exposure: a meta-analysis of cohort studies

BACKGROUND

Diesel exhaust exposure and cancer other than the lungs have been limitedly investigated.

AIMS

To conduct a systematic review and meta-analysis on the association between occupational exposure to diesel exhaust and gastrointestinal cancers.

METHODS

Two researchers performed a systematic literature review to identify all cohort studies on occupational exposure to diesel exhaust and risk of cancers other than lung. Of the 30 retained studies, 10 reported risk estimates for oesophageal, 18 on gastric, 15 on colon and 14 on rectal cancer. We performed random-effects meta-analyses to calculate summary relative risks (RRs) and 95% confidence intervals (CIs) for ever-exposure to diesel exhaust.

RESULTS

We calculated summary RR = 1.08 (95% CI 0.97-1.21, P heterogeneity = 0.06) for oesophageal, 1.06 (95% CI 0.99-1.14, P < 0.001) for gastric, 0.98 (95% CI 0.96-1.00, P = 0.453) for colon, and RR = 1.04 (95% CI 0.97-1.11, P = 0.013) for rectal cancer. Drivers showed an association with oesophageal (RR = 1.26, 95% CI 0.99-1.62), gastric (RR = 1.20, 95% CI 0.91-1.59) and rectal cancer (RR = 1.41, 95% CI 1.13-1.75); machine operators with oesophageal (RR = 1.09, 95% CI 1.00-1.20) and gastric (RR = 1.15, 95% CI 1.10-1.20) and handlers with oesophageal cancer (RR = 1.95, 95% CI 1.23-3.09). Studies from Europe revealed an association with gastric cancer while those from North America did not (P < 0.05). No difference was found by quality score except for gastric cancer, where high-quality studies but not low-quality ones showed increased risk (P heterogeneity = 0.04). There was no evidence of publication bias.

CONCLUSIONS

An increased but insignificant risk of oesophageal, gastric and rectal, but not colon cancer, was suggested in workers exposed to diesel exhaust. Residual confounding cannot be excluded.

Occupational exposure to diesel exhaust and head and neck cancer: a systematic review and meta-analysis of cohort studies

Exposure to diesel exhaust (DE) and other fossil fuels in the workplace can cause several health effects including cancer. We conducted a systematic review and meta-analysis of cohort studies examining the association between occupational DE exposure and the risk of head and neck cancer (HNC), including cancer of the oral cavity, pharynx and larynx. We included cohort studies mentioned in the Monograph of the International Agency for Research on Cancer, 2014, on DE. Forest plots of relative risk (RR) were constructed for HNC overall and its anatomical subtypes. A random-effects model was used to address heterogeneity between studies. Fifteen articles were included after removing duplicates and irrelevant reports. The summary RR for DE exposure was 1.08 [95% confidence interval (CI) = 1.01-1.17, P heterogeneity = <0.001] for HNC overall, 0.98 (95% CI = 0.87-1.11) for oral cavity, 1.05 (95% CI = 0.77-1.43) for pharyngeal, 1.15 (95% CI = 0.96-1.38) for oral cavity and pharyngeal combined, and 1.13 (95% CI = 1.03-1.24) for laryngeal cancer. There were elevated RRs for incidence studies of HNC (RR = 1.13; 95% CI = 1.05-1.22, P  = 0.001), European studies (RR = 1.13; 95% CI = 1.05-1.23, P  = 0.001), and female studies (RR = 1.77; 95% CI = 1.31-2.39, P  = 0.003). Our study suggested an association between occupational DE exposure and the risk of HNC, particularly laryngeal cancer. Although residual confounding cannot be ruled out, our results support the importance of controlling occupational DE exposure.

Influence of Rurality on Oral Cancer Trends among Organisation for Economic Co-Operation and Development (OECD) Member Countries-A Scoping Review

Oral cancer is the general term used to describe cancers of the oral cavity and oropharyngeal region. These cancers are one of the leading causes of death in elderly residents within the Organisation for Economic Co-operation and Development (OECD) member countries in the 21st century. This scoping review was carried out to assess the influence of rurality on oral cancer trends and patterns among OECD member countries. Four online databases (Medline, PubMed, Scopus, and CINAHL) were searched for studies that reported on oral cancer trends in rural and remote areas in OECD member countries. A total of 1143 articles were obtained initially; among them, 995 papers were screened to include 18 articles for this scoping review. Studies have reported increasing incidence and prevalence in the United States, Australia, Canada, and European countries wherein risk factors such as tobacco, alcohol, and human papilloma virus (HPV) infections were associated with oral and oropharyngeal cancers. Awareness among people living in rural areas about HPV-related cancers was very low, while rates of tobacco and alcohol abuse were noted to be rising more rapidly than among their urban counterparts. Furthermore, the ageing population was most affected compared to the younger age groups of people with oral and oropharyngeal cancer that are prevalent in these regions. Overall, despite living in developed countries, rurality was noted to be a significant factor in the lower life expectancy of oral cancer patients, mainly due to the limited accessibility to tertiary cancer care centres and advanced medical care.

Exposure to fibres and risk of pleural mesothelioma in the Norwegian Offshore Petroleum Workers cohort

OBJECTIVES

Pleural mesothelioma is a rare respiratory cancer, mainly caused by inhalation of asbestos fibres. Other inorganic fibres are also suggested risk factors. We aimed to investigate the association between exposure to asbestos or refractory ceramic fibres (RCFs) and pleural mesothelioma among male Norwegian offshore petroleum workers.

METHODS

Among 25 347 men in the Norwegian Offshore Petroleum Workers (NOPW) cohort (1965-1998), 43 pleural mesothelioma cases were identified through the Cancer Registry of Norway (1999-2022). A case-cohort study was conducted with 2095 randomly drawn non-cases from the cohort. Asbestos and RCF exposures were assessed with expert-made job-exposure matrices (JEMs). Weighted Cox regression was used to estimate HRs and 95% CIs, adjusted for age at baseline and pre-offshore employment with likely asbestos exposure.

RESULTS

An increased risk of pleural mesothelioma was indicated for the highest versus lowest tertile of average intensity of asbestos (HR=1.21, 95% CI: 0.57 to 2.54). Pre-offshore asbestos exposure (vs no such exposure) was associated with increased risk of pleural mesothelioma (HR=2.06, 95% CI: 1.11 to 3.81). For offshore workers with no pre-offshore asbestos exposure, an increased risk of pleural mesothelioma was found for the highest tertile of average intensity of asbestos (HR=4.13, 95% CI: 0.93 to 18), versus the lowest tertile. No associations were found between RCF and pleural mesothelioma.

CONCLUSIONS

Associations between JEM-based offshore asbestos exposure and pleural mesothelioma were confirmed in the NOPW cohort. Pleural mesothelioma risk was also associated with asbestos exposure before work in the offshore petroleum industry.

Leukemia Incidence by Occupation and Industry: A Cohort Study of 2.3 Million Workers from Ontario, Canada

Although a significant body of evidence has attributed certain occupational exposures with leukemia, such as benzene, formaldehyde, 1,3-butadiene and ionizing radiation, more research is needed to identify work environments at increased risk for this disease. Our study aimed to identify occupational and industry groups associated with an elevated incidence of leukemia using a diverse cohort of workers' compensation claimants from Ontario, Canada. A total of 2,363,818 workers in the Occupational Disease Surveillance System (ODSS) cohort, with claims between 1983-2019, were followed for malignant leukemia diagnoses up to 31 December 2019. We used a Cox proportional-hazards model to estimate the relative incidence of leukemia in specific occupation and industry groups. After adjusting for age and birth year, males in protective services (HR = 1.17, 95% CI = 1.02-1.35), metal machining (HR = 1.23, 95% CI = 1.07-1.41), transport (HR = 1.15, 95% CI = 1.06-1.25), and mining occupations (HR = 1.28, 95% CI = 1.02-1.60) had elevated risks of leukemia compared to other workers in the ODSS, with comparable findings by industry. Among female workers, slight risk elevations were observed among product fabricating, assembling, and repairing occupations, with other increased risks seen in furniture and fixture manufacturing, storage, and retail industries. These findings underscore the need for exposure-based studies to better understand occupational hazards in these settings.

Methodological and Practical Challenges in Synthesizing Occupational Cancer Studies

Studies examining occupational exposures and cancer risk frequently report mixed findings; it is thus imperative for researchers to synthesize study results and identify any potential sources that explain such variabilities in study findings. However, when synthesizing study results using meta-analytic techniques, researchers often encounter a number of practical and methodological challenges. These challenges include (1) an incomparability of effect size measures due to large variations in research methodology; (2) a violation of the independence assumption for meta-analysis; (3) a violation of the normality assumption of effect size measures; and (4) a variation in cancer definitions across studies and changes in coding standards over time. In this paper, we first demonstrate these challenges by providing examples from a real dataset collected for a large meta-analysis project that synthesizes cancer mortality and incidence rates among firefighters. We summarize how each of these challenges has been handled in our meta-analysis. We conclude this paper by providing practical guidelines for handling challenges when synthesizing study findings from occupational cancer literature.

Polymorphisms in drug-metabolizing genes and urinary bladder cancer susceptibility and prognosis: Possible impacts and future management

Epidemiological studies have shown the association of genetic variants with risks of occupational and environmentally induced cancers, including bladder (BC). The current review summarizes the effects of variants in genes encoding phase I and II enzymes in well-designed studies to highlight their contribution to BC susceptibility and prognosis. Polymorphisms in genes codifying drug-metabolizing proteins are of particular interest because of their involvement in the metabolism of exogenous genotoxic compounds, such as tobacco and agrochemicals. The prognosis between muscle-invasive and non-muscle-invasive diseases is very different, and it is difficult to predict which will progress worse. Web of Science, PubMed, and Medline were searched to identify studies published between January 1, 2010, and February 2023. We included 73 eligible studies, more than 300 polymorphisms, and 46 genes/loci. The most studied candidate genes/loci of phase I metabolism were CYP1B1, CYP1A1, CYP1A2, CYP3A4, CYP2D6, CYP2A6, CYP3E1, and ALDH2, and those in phase II were GSTM1, GSTT1, NAT2, GSTP1, GSTA1, GSTO1, and UGT1A1. We used the 46 genes to construct a network of proteins and to evaluate their biological functions based on the Reactome and KEGG databases. Lastly, we assessed their expression in different tissues, including normal bladder and BC samples. The drug-metabolizing pathway plays a relevant role in BC, and our review discusses a list of genes that could provide clues for further exploration of susceptibility and prognostic biomarkers.

Gingiva squamous-cell carcinoma in a non-smoking patient with occupational exposure to solvent siphoning using mouth: case report and literature review

Background

While overall head and neck cancer incidence decreases due to reduced tobacco and alcohol consumption, the incidence of HPV negative oral cavity squamous cell carcinoma (SCC) is raising in several industrialized countries, especially in non-smoking and non-drinking patients.

Case presentation

We document a case of gingiva SCC in a 56 years old never-smoker patient reporting low alcohol consumption and unusual occupational solvent exposure. The HPV-negative lesion was surgically removed in 2018, and the patient remains in complete remission 4 years after recurrent surgery in 2019. In 2021, the patient was referred to the occupational cancer consultation. The patient worked as screen printer for 18 years. He reported mouth siphoning every 2-3 days to transfer organic solvents (mainly aromatic hydrocarbons and ketones) from containers into smaller recipients, with regular passage of solvents into his mouth.

Conclusion

According to the literature, the frequency of solvent siphoning using mouth is likely to be underestimated. While our review did not find studies reporting longterm consequences to the oral cavity of mouth siphoning, current evidence supports a positive association of upper aero digestive tract SCC with occupational exposures to organic solvents and printing processes. In absence of major extraprofessional factors, the HPV-negative gingiva SCC of this patient might be attributable to the regular occupational oral solvent exposure. While the available evidence remains limited to formally establish a causal relationship, clinicians should investigate this hazardous work practice in patients with OSCC and history of solvent exposures.

Lived Experiences and Fear of Cancer Recurrence Among Survivors of Localized Cutaneous Melanoma

Importance

Most of the rapid increase in cutaneous melanoma incidence in the US has been localized disease that is treated surgically and is associated with high survival rates. However, little is known about the psychological well-being of survivors in the US.

Objective

To explore the lived experiences and fear of cancer recurrence among survivors of localized cutaneous melanoma.

Design, Setting, and Participants

This was a qualitative and survey-based study that used semistructured interviews and the Fear of Cancer Recurrence Inventory short form (FCRI-SF) survey tool with participants recruited from an academic dermatology practice affiliated with the University of Texas, Austin. Interviews were completed via telephone or in person from August 2021 to September 2022. Each of the 9 items in the FCRI-SF was rated on a 5-point Likert scale, scored from 0 to 4, with a maximum possible score of 36 points. Data analyses were performed from February 2022 to June 2023.

Main Outcomes and Measures

Semistructured interviews were analyzed for themes and subthemes associated with the lived experiences of survivors of cutaneous melanoma. The FCRI-SF scores were tabulated, with scores of 13 or greater identifying potential cases of clinically significant fear of cancer recurrence.

Results

In all, 51 participants (mean [SD] age, 49.5 [11.7] years; 34 [67%] female and 17 [33%] male) with a history of localized melanoma (stage 0-IIA) completed the interview and survey. Among them, 17 (33%) had survived a diagnosis of stage 0 melanoma, and the remainder, at least 1 invasive melanoma diagnosis (stage I-IIA). Semistructured interviews revealed several themes: (1) emotions surrounding follow-up appointments, (2) intensity of melanoma surveillance, (3) lifestyle changes regarding sun exposure, and (4) thoughts about life and death. Thirty-eight of 51 participants had an FCRI-SF score above the threshold for clinical fear of cancer recurrence.

Conclusions and Relevance

This qualitative and survey-based study found that despite having an excellent prognosis, some survivors of localized melanoma, even those who had stage 0, have high rates of fear of cancer recurrence and intense survivorship experiences that affect their psychological well-being.

Occupation and tongue cancer in Nordic countries

PURPOSE

Almost 200,000 tongue cancers were diagnosed worldwide in 2020. The aim of this study was to describe occupational risk variation in this malignancy.

METHODS

The data are based on the Nordic Occupational Cancer (NOCCA) study containing 14.9 million people from the Nordic countries with 9020 tongue cancers diagnosed during 1961-2005. The standardized incidence ratio (SIR) of tongue cancer in each occupational category was calculated using national incidence rates as the reference.

RESULTS

Among men, the incidence was statistically significantly elevated in waiters (SIR 4.36, 95% confidence interval (CI) 3.13--5.92), beverage workers (SIR 3.42, 95% CI 2.02-5.40), cooks and stewards (SIR 2.55, 95% CI 1.82-3.48), seamen (SIR 1.66, 95% CI 1.36-2.00), journalists (SIR 1.85, 95% CI 1.18-2.75), artistic workers (SIR 2.05, 95% CI 1.54-2.66), hairdressers (SIR 2.17, 95% CI 1.39-3.22), and economically inactive persons (SIR 1.57, 95% CI 1.42-1.73). Among women, the SIR was statistically significantly elevated only in waitresses (SIR 1.39, 95% CI 1.05-1.81). Statistically significant SIRs ≤ 0.63 were observed in male farmers, gardeners, forestry workers and teachers, and in female launderers.

CONCLUSIONS

These findings may be related to consumption of alcohol and tobacco, but the effect of carcinogenic exposure from work cannot be excluded.

Risk of bladder, kidney and prostate cancer from occupational exposure to welding fumes: a systematic review and meta-analysis

BACKGROUND

Our aimed to conduct a meta-analysis of cohort studies on risk of genitourinary (GU) cancers in workers exposed to welding fumes (WF).

METHODS

We performed a systematic review of studies published on Pubmed, Scopus and Embase following PRISMA criteria. Two researchers selected cohort studies on WF exposure. From 2582 articles, 7 non-overlapping studies were included. Quality of studies was scored according to CASP. We run a random effects meta-analysis to calculate the relative risk (RR) and 95% confidence intervals (CI) of GU cancer, overall and stratified by cancer, country, and quality score.

RESULTS

We included seven studies reporting results on GU cancers, including prostate, bladder and kidney cancer (PC, BC, and KC). The RR was 1.19 (95% CI = 1.07-1.32, 16 risk estimates) for GU cancer; 1.13 (95% CI = 0.90-1.42, 4 risk estimates) for PC; 1.26 (95% CI = 0.98-1.60, 7 risk estimates) for BC and 1.28 (95% CI = 1.12-1.47, 5 risk estimates) for KC. Heterogeneity was present in all meta-analyses (p < 0.001). The increased risk was more pronounced in North American than in European studies (respectively, OR = 1.35, 95% CI = 1.18-1.55; OR = 1.13, 95% CI = 1.01-1.27 p heterogeneity = 0.03). There was no heterogeneity according to quality score (p = 0.4). Data were insufficient to investigate associations by industry or welding type. Publication bias for each cancer was excluded.

CONCLUSION

This meta-analysis suggests increased risk of KC and BC, but not of PC, in workers exposed to WF. Confounding by other occupational and non-occupational risk factors could not be excluded. Data were not adequate to address the risk of specific exposure circumstances.

A review for the impacts of circadian disturbance on urological cancers

Circadian rhythm is an internal timing system and harmonizes a variety of cellular, behavioral, and physiological processes to daily environment. Circadian disturbance caused by altered life style or disrupted sleep patterns inevitably contributes to various disorders. As the rapidly increased cancer occurrences and subsequent tremendous financial burdens, more researches focus on reducing the morbidity rather than treating it. Recently, many epidemiologic studies demonstrated that circadian disturbance was tightly related to the occurrence and development of cancers. For urinary system, numerous clinical researches observed the incidence and progress of prostate cancer were influenced by nightshift work, sleep duration, chronotypes, light exposure, and meal timing, this was also proved by many genetic and fundamental findings. Although the epidemiological studies regarding the relationship between circadian disturbance and kidney/bladder cancers were relative limited, some basic researches still claimed circadian disruption was closely correlated to these two cancers. The role of circadian chemotherapy on cancers of prostate, kidney, and bladder were also explored, however, it has not been regularly recommended considering the limited evidence and poor standard protocols. Finally, the researches for the impacts of circadian disturbance on cancers of adrenal gland, penis, testis were not found at present. In general, a better understanding the relationship between circadian disturbance and urological cancers might help to provide more scientific work schedules and rational lifestyles which finally saving health resource by reducing urological tumorigenesis, however, the underlying mechanisms are complex which need further exploration.

Prevalent occupational exposures and risk of lung cancer among women: Results from the application of the Canadian Job-Exposure Matrix (CANJEM) to a combined set of ten case-control studies

BACKGROUND

Worldwide, lung cancer is the second leading cause of cancer death in women. The present study explored associations between occupational exposures that are prevalent among women, and lung cancer.

METHODS

Data from 10 case-control studies of lung cancer from Europe, Canada, and New Zealand conducted between 1988 and 2008 were combined. Lifetime occupational history and information on nonoccupational factors including smoking were available for 3040 incident lung cancer cases and 4187 controls. We linked each reported job to the Canadian Job-Exposure Matrix (CANJEM), which provided estimates of probability, intensity, and frequency of exposure to each selected agent in each job. For this analysis, we selected 15 agents (cleaning agents, biocides, cotton dust, synthetic fibers, formaldehyde, cooking fumes, organic solvents, cellulose, polycyclic aromatic hydrocarbons from petroleum, ammonia, metallic dust, alkanes C18+, iron compounds, isopropanol, and calcium carbonate) that had lifetime exposure prevalence of at least 5% in the combined study population. For each agent, we estimated lung cancer risk in each study center for ever-exposure, by duration of exposure, and by cumulative exposure, using separate logistic regression models adjusted for smoking and other covariates. We then estimated the meta-odds ratios using random-effects meta-analysis.

RESULTS AND CONCLUSIONS

None of the agents assessed showed consistent and compelling associations with lung cancer among women. The following agents showed elevated odds ratio in some analyses: metallic dust, iron compounds, isopropanol, and organic solvents. Future research into occupational lung cancer risk factors among women should prioritize these agents.

Occupational-related exposure to diesel exhaust and risk of leukemia: systematic review and meta-analysis of cohort studies

PURPOSE

Diesel exhaust (DE) is an established lung carcinogen. The association with leukemia is not well established. We conducted a systematic review and meta-analysis of cohort studies to determine the association between occupational DE exposure and risk of leukemia.

METHODS

A systematic literature review was performed to identify all cohort studies on occupational exposure to DE and associated risk of leukemia. STROBE guidelines and PECOS criteria were followed. Meta-analyses with fixed effects (and random-effects model in cases of high heterogeneity) were performed to calculate summary relative risks (RR) and 95% confidence intervals (CI), including subgroup analyses by outcome (mortality or incidence), sex, geographic region, industry type, and study quality. Study quality was assessed using the the Joanna Briggs Institute (JBI) critical appraisal checklist for cohort studies.

RESULTS

Of the 30 studies retained, 20 (8 from North America, 12 from Europe) reported a total of 33 estimates of the risk of leukemia. Overall, the relative risk (RR) of leukemia was 1.01 (95% CI = 0.97-1.05, I2 = 21.2%, n = 33); corresponding results for leukemia incidence and mortality were RR = 1.02 (95% CI = 0.98-1.06, I2 = 27.9%, n = 19) and RR = 0.91 (95% CI = 0.81-1.02, I2 = 0.0%, n = 15), respectively. The main results were confirmed in analyses by sex and geographic area. A statistically significant association was detected for miners (RR = 1.58, 95% CI = 1.15-2.15, I2 = 77.0%, n = 2) but not for other occupational groups. Publication bias was not detected (p = 0.7).

CONCLUSION

Our results did not indicate an association between occupational DE exposure and leukemia, with the possible exception of miners. Residual confounding cannot be excluded.

Occupational exposure to diesel exhausts and liver and pancreatic cancers: a systematic review and meta-analysis

BACKGROUND

Diesel exhaust (DE) is human carcinogen with sufficient evidence only for lung cancer. Systematic evidence on other cancer types is scarce, thus we aimed to systematically review current literature on the association between occupational DE exposure and risk of liver and pancreatic cancers.

METHODS

We performed a systematic literature review to identify cohort studies on occupational DE exposure and risk of cancers other than lung. We computed pooled relative risks (RRs) and corresponding 95% confidence intervals (CIs) for liver and pancreatic cancers using DerSimonian and Laird random-effects model.

RESULTS

Fifteen studies reporting results on pancreatic cancer and fourteen on liver cancer were included. We found a weakly increased risk of pancreatic cancer in workers exposed to DE (RR: 1.07, 95% CI: 1.00, 1.14), mainly driven by results on incidence (RR: 1.11, 95% CI: 1.02, 1.22). As for liver cancer, results were suggestive of a positive association (RR: 1.09; 95% CI: 0.99, 1.19), although a significant estimate was present in studies published before 2000 (RR: 1.41; 95% CI: 1.09, 1.82). We found no compelling evidence of publication bias.

CONCLUSIONS

Our findings suggest an association between occupational DE exposure and liver and pancreatic cancer. Further studies with detailed exposure assessment, environmental monitoring data, and appropriate control for confounders are warranted.

Agricultural exposure and risk of ovarian cancer in the AGRIculture and CANcer (AGRICAN) cohort

BACKGROUND

Ovarian cancer is rare with a poor prognosis and few established risk factors. Hormones and reproductive factors significantly impact its development, suggesting a potential link with endocrine disrupters.

METHODS

In the AGRICAN cohort, 59 391 female farmers completed data on lifelong agricultural exposures and reproductive life. Cox models with attained age as timescale (HR and 95% CI) were used. The role of hormonal factors as potential confounders was considered along with specific time windows for exposure (childhood, puberty and menopause). Female farmers were the reference group (for the principal analyses).

RESULTS

Between enrolment (2005-2007) and the end of follow-up (31 December 2017), 262 incident ovarian cancers were identified. An increased risk was observed for females involved in pigs (HR=2.12 (95% CI 1.27 to 3.52)) including during puberty (HR=1.83 (95% CI 1.13 to 2.94)), fruit-growing (HR=2.17 (95% CI 1.09 to 4.30)) and potato seed treatment (HR=2.81 (95% CI 1.29 to 6.09)). Conversely, females born on farms growing grain cereals (HR=0.64 (95% CI 0.46 to 0.90)) or pig-breeding (HR=0.78 (95% CI 0.55 to 1.12)) presented a reduced risk of ovarian cancer. Triazine herbicide exposure was not associated with ovarian cancer. The effect of agricultural exposures remained unchanged in multivariate models considering contraception, parity, puberty age, menopause age and body mass index.

CONCLUSION

This study is the first to assess the association between specific agricultural exposures and ovarian cancer comprehensively. Some of the positive associations observed suggest that some pesticide exposure (especially during puberty) could play a role in the development of ovarian cancer. On the other hand, agricultural exposure during early life could have a protective effect, as observed for lung cancer among farmers. Finally, we did not confirm the previous putative effect of exposure to triazine herbicides.

Occupational variation in incidence of oropharyngeal cancer in the Nordic countries

PURPOSE

Evaluate the occupational variation in incidence of oropharyngeal cancer (OPC).

METHODS

We calculated standardized incidence ratios (SIRs) of OPC in occupational categories in the Nordic countries relative to the entire national populations. The data covered 6155 OPC cases.

RESULTS

Among men high risk of OPC was observed, among else, in waiters (SIR 6.28, 95% CI 4.68-8.26), beverage workers (SIR 3.00, 95% CI 1.72-4.88), and artistic workers (SIR 2.97, 95% CI 2.31-3.76). Among women high risk of OPC was observed in waiters (SIR 2.02, 95% CI 1.41-2.81) and packers (SIR 1.73, 95% CI 1.07-2.64). The lowest SIRs were observed in female gardeners (SIR 0.27, 95% CI 0.12-0.51) and male farmers (SIR 0.30, 95% CI 0.25-0.35).

CONCLUSION

The 20-fold variation in incidence of OPC between occupations needs further investigation in studies with detailed information on occupational and non-occupational risk factors.

Personal exposure to gaseous and particulate phase polycyclic aromatic hydrocarbons (PAHs) and nanoparticles and lung deposited surface area (LDSA) for soot among Norwegian chimney sweepers

Exposure to polycyclic aromatic hydrocarbons (PAHs) of high molecular weight from chimney soot can cause cancer among chimney sweepers. These sweepers may also be exposed to high concentrations of nanosized particles, which can cause significant inflammatory responses due to their relatively greater surface area per mass. In this study, the authors aimed to assess the exposure profiles of airborne personal exposure to gaseous and particulate PAHs, and real-time samples of the particle number concentrations (PNCs), particle sizes, and lung-deposited surface areas (LDSAs), for chimney sweepers in Norway. Additionally, the authors aimed to assess the task-based exposure concentrations of PNCs, sizes, and LDSAs while working on different tasks. The results are based on personal samples of particulate PAHs (n = 68), gaseous PAHs (n = 28), and real-time nanoparticles (n = 8) collected from 17 chimney sweepers. Samples were collected during a "typical work week" of chimney sweeping and fire safety inspections, then during a "massive soot" week, where larger sweeping missions took place. Significantly higher PAH concentrations were measured during the "massive soot" week compared to the "typical work week," however, the time-weighted average (TWA) (8-hr) of all gaseous and particulate PAHs ranged from 0.52 to 4.47 µg/m3 and 0.49 to 2.50 µg/m3, respectively, well below the Norwegian occupational exposure limit (OEL) of 40 µg/m3. The PNCs were high during certain activities, such as emptying the vacuum cleaner. Additionally, during 2 days of sweeping in a waste sorting facility, the TWAs of the PNCs were 3.6 × 104 and 7.1 × 104 particles/cm3 on the first and second days, respectively, which were near and above the proposed nano reference limit TWA value of 4.0 × 104 particles/cm3 proposed by the International Workshop on Nano Reference Values. The corresponding TWAs of the LDSAs were 49.5 and 54.5 µm2/cm3, respectively. The chimney sweepers seemed aware of the potential health risks associated with exposure, and suitable personal protective equipment was used. However, the PNCs reported for the activities show that when the activities change or increase, the PNCs' TWAs can become unacceptably high.

Survival in oral and pharyngeal cancers is catching up with laryngeal cancer in the NORDIC countries through a half century

BACKGROUND

Cancers of the head and neck (HN) are heterogeneous tumors with incidence rates varying globally. In Northern Europe oral and oropharyngeal cancers are the most common individual types. Survival for HN varies by individual tumor type but for most of them survival trends are not well known over extended periods of time.

METHODS

Data for a retrospective survival study were obtained for Danish, Finnish, Norwegian, and Swedish patients from the NORDCAN database from 1971 to 2020. Relative 1- and 5-year survival rates and 5/1-year conditional survival for years 2-5 were calculated.

RESULTS

Both 1- and 5-year survival improved for all HN cancers but only marginally for laryngeal cancer. For the other cancers a 50-year increase in 5-year survival was about 30% units for nasopharyngeal and oropharyngeal cancers, 20% units for oral cancer and somewhat less for hypopharyngeal cancer.

CONCLUSIONS

5-year survival reached about 65% for all HN cancers, except for hypopharyngeal cancer (30%). Human papilloma virus infection is becoming a dominant risk factor for the rapidly increasing oropharyngeal cancer, the prevention of which needs to emphasize oral sex as a route of infection.

Occupational asbestos exposure and ovarian cancer: updated systematic review

BACKGROUND

The association between asbestos exposure and ovarian cancer has been questioned given the possible misdiagnosis of peritoneal mesothelioma as ovarian cancer.

AIMS

To update a systematic review on ovarian cancer risk in women occupationally exposed to asbestos, exploring the association with the time since first exposure and the duration of exposure.

METHODS

We searched PubMed from 2008 onwards, screened previous systematic reviews, combined standardized mortality ratios (SMR) using random effect models and quantified heterogeneity using the I2 statistic. To assess tumour misclassification, we compared the distribution of observed excess ovarian cancers (OEOC) to that expected (EEOC) from the distribution of peritoneal cancers in strata of latency and exposure duration.

RESULTS

Eighteen publications (20 populations), including a pooled analysis of 21 cohorts, were included. The pooled SMR was 1.79 (95% confidence interval 1.38-2.31), with moderate heterogeneity between studies (I2 = 42%), based on 144 ovarian cancer deaths/cases. The risk was increased for women with indirect indicators of higher exposure, longer duration and latency, and lower for chrysotile than for crocidolite exposure. The effect of duration and latency could not be completely disentangled, since no multivariate analysis was available for time-related variables. The dissimilarity index between OEOC and EEOC for the time since first exposure was small suggesting a similar pattern of risk.

CONCLUSIONS

While some misclassification between ovarian and peritoneal cancers cannot be excluded, the observed excess risk of ovarian cancer should be added to the overall disease burden of asbestos.

Mortality, cancer incidence, and disability among professional drivers in Slovenia

Literature data about all-cause and cause-specific mortality among professional drivers are inconsistent. Most studies report lower all-cause and higher cause-specific mortality. Higher cause-specific mortality is most often the result of malignant and circulatory diseases. The aim of our retrospective cohort study was to get a better insight into the mortality, cancer incidence, and occupational disability of the entire professional driver population in Slovenia (N=8,231) from 1997 to 2016 through standardised mortality ratio (SMR), standardised proportional mortality ratio (SPMR), standardised cancer incidence ratio (SIR), and standardised disability ratio (SDR). Total mortality was significantly lower than that of the general working population (SMR=0.49; 95 % CI=0.44-0.55). When SPMR was calculated, however, the risk of all-cause mortality increased to 1 (SPMR=1.00; 95 % CI=0.89-1.12), of cancer-related mortality to 1.13 (95 % CI=0.94-1.35), and of injury-related mortality to 1.25 (95 % CI=0.97-1.59). Cancer incidence was lower than in the general male working population for all types of cancer (SIR=0.66; 95 % CI=0.59-0.72), lung cancer included (SIR=0.56; 95 % CI=0.41-0.73). Occupational all-cause and cause-specific disability were also lower than in the rest of the working population. Even though all types of cancer and injuries were established among professional drivers in Slovenia, no major risk stand out. However, our findings may have been skewed by the healthy worker effect.

Analyzing the incidence of silicosis across various industries in Taiwan: a study of occupational disease surveillance by linking national-based workers' and medicoadministrative databases

OBJECTIVES

This study aimed to establish an occupational disease surveillance system by identifying high-risk industries for silicosis in Taiwan using a national database linkage approach.

METHODS

The study was based on a comprehensive analysis of benefit claims from the National Labor Insurance Research Database and medical records from the National Health Insurance Research Database between 2004 and 2020, providing coverage for more than 88.5% of the workforce and 99.9% of citizens. Silicosis was defined as having received compensation for labor insurance benefits or having received a diagnosis of silicosis (International Classification of Diseases, 10th Revision: J62 or International Classification of Diseases, Ninth Revision: 502). The study used the International Standard Industrial Classification of All Economic Activities for industry-specific classification. Cox proportional hazard models were used to compare the silicosis incidence and risk among each industry and identify high-risk industries for silicosis.

RESULTS

This study analyzed 1466 cases of silicosis between 2004 and 2020 and found that 28 industries had incidence rates of over 40 cases per 100,000 workers, indicating more than double the risk of developing silicosis. Of these industries, 14 were considered high risk (relative risk of over four times). Among these, this study identified industries rarely mentioned in the past, such as wholesale of brick, sand, cement, and products, artistic creation, landscape construction, and materials recovery. Stratification by years of work experience reveals those industries such as quarrying of stone, sand, clay, and other mining, construction of buildings, landscape construction, site preparation, foundation and structure construction, building completion and finishing, manufacture of ships, boats, and floating structures, and plumbing, heat, and air conditioning installation display higher hazard ratios for individuals with <10 years of work experience.

CONCLUSIONS

The current surveillance system has identified certain industries that are at a higher risk of developing silicosis, which could be used for future occupational epidemiological surveys and targeted preventive measures in these sectors.

Occupational Etiology of Oropharyngeal Cancer: A Literature Review

While abundant evidence exists linking alcohol, tobacco, and HPV infection to a carcinogenic impact on the oropharynx, the contribution of inhalational workplace hazards remains ill-defined. We aim to determine whether the literature reveals occupational environments at a higher-than-average risk of developing oropharyngeal cancer (OPC) and summarize the available data. To identify studies assessing the relationship between occupational exposure and risk of OPC, a search of the literature through the PubMed-NCBI database was carried out and, ultimately, 15 original articles meeting eligibility criteria were selected. Only original articles in English focusing on the association between occupational exposure and risk or death of specifically OPC were included. The available data are supportive of a potentially increased risk of OPC in waiters, cooks and stewards, artistic workers, poultry and meat workers, mechanics, and World Trade Center responders exposed to dust. However, the available literature on occupation-related OPC is limited. To identify occupational categories at risk, large cohorts with long follow-ups are needed. Identification of causal associations with occupation-related factors would require dose-response analyses adequately adjusted for confounders.

Cancer incidence among visual artists: 45 years of follow-up in four Nordic countries

INTRODUCTION

Professional visual artists constitute a heterogeneous vocational group, including, but not limited to painters, photographers, textile artists, and sculptors who may face exposure to workplace hazardous substances and lifestyle factors that may contribute to the development of selected cancers. The objective of this registry-based cohort study was to assess the cancer incidence among Nordic visual artists.

MATERIALS AND METHODS

This study is based on data from the Nordic Occupational Cancer (NOCCA) project that combines census data of 15 million people from all Nordic countries and cancer registries from 1961 to 2005. For the present study we selected a cohort of visual artists from Finland, Iceland, Norway, and Sweden. Standardized incidence ratio (SIR) analyses were conducted with the cancer incidence rates for the entire national study populations used as reference rates.

RESULTS

In male visual artists, there were statistically significant excesses in cancers of the tongue (SIR 2.91, 95% confidence interval 1.74-4.55), oral cavity (2.09, 1.26-3.27), pharynx (2.18, 1.45--3.15), testis (1.91, 1.11-3.05), renal pelvis (2.48, 1.42-4.03) and bladder (1.33, 1.14-1.55). The risk was significantly decreased for cancers of the lip (0.45, 0.18-0.93) and stomach (0.65, 0.50-0.84). In female visual artists, the only significantly increased risk was observed for breast cancer (1.29, 1.13-1.48) and the only significantly decreased risk for stomach cancer (0.43, 0.17-0.88). The incidence of lung cancer was close to the population average in both sexes.

CONCLUSIONS

The non-elevated incidence of lung cancer suggests a similar prevalence of smoking between visual artists and the general population, while the elevated risk of cancers of mouth and pharynx among male visual artists is suggestive of more widespread alcohol drinking. The excess risk of urogenital cancers might be associated with exposure to solvents.

Occupational exposure to cosmetic talc and mesothelioma in barbers, hairdressers, and cosmetologists: A systematic review of the epidemiology

Inhalation exposure to cosmetic talc has generated much scientific debate regarding its potential as a risk factor for mesothelioma, a rare, but fatal cancer. Barbers, hairdressers, and cosmetologists have regularly used cosmetic talc-containing products, but the collective epidemiological evidence for mesothelioma in these occupations has yet to be described. As such, we conducted a systematic review of PubMed and the National Institute for Occupational Safety and Health's (NIOSH) Numbered Publications list to identify original epidemiological literature reporting measures of association between these occupations and incidence of or death from mesothelioma. Literature screening was performed independently twice, the results of which were summarized and tabulated and underwent a review for their accuracy. A total of 12 studies met our inclusion criteria, including three cohort, six case-control, and three proportionate mortality/registration studies. The data from these studies were collected in 13 European and North American countries, spanning more than 50 years. We supplemented this review with queries of occupational mortality databases that are managed by the Washington State Department of Health and NIOSH for 26 U.S. states. Most findings were null and if statistically significant, nearly all showed an inverse relationship, indicative of a protective effect of these occupations on mesothelioma risk. Overall, the epidemiological evidence does not support an increased risk of mesothelioma for these occupations. This research fills an important data gap on the etiology of mesothelioma in barbers, hairdressers, and cosmetologists, and provides a benchmark for those with comparatively less exposure, such as non-occupational users of similar cosmetic talc-containing products.

Daytime, evening, and overnight: the 24-h radiology cycle and impact on interpretative accuracy

PURPOSE

To assess the influence of time of day when a study is interpreted on discrepancy rates for common and advanced studies performed in the acute community setting.

METHODS

This retrospective study used the databank of a U.S. teleradiology company to retrieve studies between 2012 and 2016 with a preliminary report followed by a final report by the on-site client hospital. Neuroradiology, abdominal radiology, and musculoskeletal radiology studies were included. Teleradiologists were fellowship trained in one of these subspecialty areas. Daytime, evening, and overnight times were defined. Associations between major and minor discrepancies, time of day, and whether the study was common or advanced were tested with significance set at p = .05.

RESULTS

A total of 5,883,980 studies were analyzed. There were 8444 major discrepancies (0.14%) and 17,208 minor discrepancies (0.29%). For common studies, daytime (0.13%) and evening (0.13%) had lower major discrepancy rates compared to overnight (0.14%) (daytime to overnight, RR = 0.57, 95%CI: 0.45, 0.72, p < 0.01 and evening to overnight, RR = 0.57, 95%CI: 0.49,0.67, p < 0.01). Minor discrepancy rates for common studies were decreased for evening (0.29%) compared to overnight (0.30%) (RR = 0.89, 95%CI: 0.80,0.99, p = 0.029). For advanced studies, daytime (.15%) had lower major discrepancy rates compared to evening (0.20%) and overnight (.23%) (daytime to evening, RR = 0.77, 95%CI: 0.61, 0.97, p = 0.028 and daytime to overnight, RR = 0.66, 95%CI: 0.50, 0.87, p ≤ 0.01).

CONCLUSION

Significantly higher major discrepancy rates for studies interpreted overnight suggest the need for radiologists to exercise greater caution when interpreting studies overnight and may require practice management strategies to help optimize overnight work conditions. The lower major discrepancy rates on advanced studies interpreted during the daytime suggest the need for reserving advanced studies for interpretation during the day when possible.

Review of sociodemographic risk factors for presentation with advanced non-melanoma skin cancer

PURPOSE

Non-melanoma skin cancers (NMSC) are often localized and associated with an excellent prognosis but a minority present with locally advanced or metastatic disease requiring extensive resection or systemic treatment. Medical factors that increase the risk of advanced skin cancers such as tobacco use, systemic immunosuppression or genetic syndromes have been described but the sociodemographic risk factors are relatively uninvestigated and under reported. In this review a cohort of patients presenting with periorbital NMSC is reviewed for social determinants of health correlated with presentation with advanced disease.

METHODS

Patients presenting with periorbital NMSC during a 10-year period are categorized as advanced (those tumors requiring extensive local resection, sacrifice of the globe or systemic therapy) or non-advanced and demographic features are compared between the two groups.

RESULTS

274 cases of periorbital NMSC were classified as either non-advanced (177) or advanced (97). Patients with public safety net health insurance were twice as likely to present with advanced disease (25% vs 13%). Patients with advanced disease were significantly less likely to be under the care of a primary care physician, lived in economically depressed areas with lower mean household incomes, and lived further from tertiary medical care.

CONCLUSION

Financial and sociodemographic features are strongly associated with presentation with advanced NMSC. Further work is needed to determine which sociodemographic features are independent risk factors. A better understanding of the relevant barriers to care may reduce the burden of advanced disease at presentation in the future.

Socioeconomic status and lifestyle patterns in the most common cancer types-community-based research

INTRODUCTION

As the global burden of chronic cancer increases, its correlation to lifestyle, socioeconomic status (SES) and health equity becomes more important. The aim of the present study was to provide a snapshot of the socioeconomic and lifestyle patterns for different cancer types in patients at a Nordic tertiary cancer clinic.

MATERIALS AND METHODS

In a descriptive observational study, questionnaires addressed highest-attained educational level, occupational level, economy, relationship status, exposures, and lifestyle habits. The questionnaire was distributed to all cancer patients attending the cancer clinic. Treating physicians added further information about the cancer disease, including primary origin, pathology report, TNM-classification and stage.

RESULTS

Patients with lung cancer had the lowest SES, and patients with gastrointestinal (GI) cancer, other cancer types and prostate cancer had the second, third and fourth lowest SES, respectively. However, breast cancer patients had the highest SES. Lifestyle and exposure patterns differed among the major cancer types. Lung cancer patients reported the highest proportion of unfavourable lifestyle and exposure patterns, and patients with GI cancer, prostate cancer and other cancer types had the second, third and fourth highest proportion of unfavourable lifestyle and exposure patterns, respectively. The most favourable exposure and lifestyle patterns were observed in breast cancer patients.

CONCLUSIONS

The present study indicated significant socioeconomic and lifestyle differences among cancer types at a Nordic cancer centre, with differences in lifestyle being more prominent than socioeconomic differences.

Lifelong differences in cancer incidence and mortality between subgroups of similar socioeconomic status in the Royal Norwegian Navy

OBJECTIVES

In a previous cohort study of 28 300 Navy servicemen, vessel crews showed higher cancer incidence and mortality than did land-based personnel. We have extended the follow-up to look for changes in cancer risk, and to explore temporal trends in cancer incidence and cancer mortality during more than six decades of follow-up.

METHODS

Cancer incidence and total cancer mortality were compared with the general population by calculating standardised ratios (standardised incidence ratios (SIRs), standardised mortality ratios) for the entire follow-up, with temporal trends through seven consecutive 10-year time spans from individual entry to follow-up. Rates were compared between the subgroups using Poisson regression, expressed as rate ratios (RRs).

RESULTS

Cancer incidence in Navy servicemen suggested a healthy soldier effect limited to the first three decades of follow-up and confined to land-based personnel. Overall, vessel crews showed 13% higher cancer incidence and 36% higher cancer mortality than other Navy servicemen. Some of the differences may be explained by a higher risk in vessel crews of cancers known to have less than 25% 5-year relative survival (RR=1.71), such as cancers of the lung, liver, pancreas and mesothelioma.

CONCLUSION

Through most of the observation time, vessel crews had an overall cancer SIR that was higher than that of land-based personnel. Much of this excess involved cancers with a generally poor prognosis, linked to lifestyle and work environment. The contrasts in cancer incidence and mortality between the two subgroups of Navy servicemen persisted through more than six decades.

Self-reported symptoms in Swedish hairdressers and association with exposure to volatile organic compounds (VOCs), including aldehydes

BACKGROUND

Working as a hairdresser involves combined exposure to multiple chemicals in hair treatment products that may induce symptoms in airways and skin.

METHODS

In this cross-sectional study, perceived symptoms among Swedish hairdressers at 10 hair salons were surveyed through a questionnaire. Associations with personal exposure to volatile organic compounds (VOCs), including aldehydes, and their corresponding hazard index (HI), based on the estimated risk for non-cancer health effects, were examined. The prevalence of four out of 11 symptoms was compared to available reference datasets from two other studies of office workers and school staff.

RESULTS

All 11 surveyed symptoms were reported among the hairdressers (n = 38). For the whole study group, the most prevalent symptoms were dripping nose (n = 7) and headache (n = 7), followed by eczema (n = 6), stuffed nose (n = 5), cough (n = 5) and discomfort with strong odors (n = 5). Significant relationships between exposure and symptoms were scarce. The exception was total VOC (TVOC) exposure adjusted to worked years in the profession; a difference was observed for any symptom between hairdressers in the group with 20 + years compared to 0-5 years in the profession (logistic regression, OR 0.03, 95% CI 0.001-0.70). Out of the four symptoms available for comparison, the prevalence of headache and cough was significantly higher in hairdressers than in controls (OR 5.18, 95% CI 1.86-13.43 and OR 4.68, 95% CI 1.17-16.07, respectively).

CONCLUSIONS

Adverse health effects related to occupation was common among the hairdressers, implying a need for exposure control measures in hair salons. Symptoms of headache and cough were more frequently reported by hairdressers than staff in offices and schools. A healthy worker effect among the hairdressers was indicated in the group with 20 + years compared to 0-5 years in the profession. Significant relationships between measured exposure and symptoms were scarce but gave information about advantages and disadvantages of the different exposure measures. The study design could be improved by increasing the size of the study population, using a better match of reference data and increasing the applicability and representability over time of the measured exposure.

No Excess Cancer Risk among Veterinarians in Denmark, Finland, Iceland, Norway, and Sweden after the 1980s

The cancer profile of veterinarians has received little research attention, despite the profession potentially being exposed to a wide range of known and suspected carcinogens. In this large-scale cohort study, we assessed cancer incidence in veterinarians in Denmark, Finland, Iceland, Norway, and Sweden, across more than 40 years (1961-2005). The cohort comprised 4708 veterinarians and 119,503 person-years at follow-up. The overall cancer incidence in veterinarians was close to the incidence in the total population in all countries and in all age groups. In male veterinarians, the standardized incidence ratios (SIR) in 1961-1990 were elevated for colon cancer (1.86, 95% confidence interval (CI) 1.39-2.44), prostate cancer (1.35, 95% CI 1.07-1.67), and especially skin melanoma (3.62, 95% CI 2.78-2.84), while there was no longer any statistically significant excess in the more recent follow-up period. Decreased SIRs were observed for lip cancer (0.11, 95% CI 0.00-0.62), laryngeal cancer (0.38, 95% CI 0.12-0.89), lung cancer (0.59, 95% CI 0.47-0.74), and stomach cancer (0.58, 95% CI 0.38-0.86), without a marked change in SIR over time. Non-significant excesses among male veterinarians were also observed in Hodgkin lymphoma (1961-1990 only), and leukaemia. This multi-country study indicates that there was an elevated incidence of several cancer types among male veterinarians before the 1990s but not after that. Some of the findings might rather be attributed to lifestyle factors and not directly to work conditions, but the excess risk of cancers of kidney and bladder, for example, might be related to work exposures.

Pleural mesothelioma risk in the construction industry: a case-control study in Italy, 2000-2018

OBJECTIVES

Workers in the construction industry have been exposed to asbestos in various occupations. In Italy, a National Mesothelioma Registry has been implemented more than 20 years ago. Using cases selected from this registry and exploiting existing control data sets, we estimated relative risks for pleural mesothelioma (PM) among construction workers.

DESIGN

Case-control study.

SETTING

Cases from the National Mesothelioma Registry (2000-2018), controls from three previous case-control studies.

METHODS

We selected male PM incident cases diagnosed in 2000-2018. Population controls were taken from three studies performed in six Italian regions within two periods (2002-2004 and 2012-2016). Age-adjusted and period-adjusted unconditional logistic regression models were fitted to estimate odds ratios (OR) for occupations in the construction industry. We followed two approaches, one (primary) excluding and the other (secondary) including subjects employed in other non-construction blue collar occupations for >5 years. For both approaches, we performed an overall analysis including all cases and, given the incomplete temporal and geographic overlap of cases and controls, three time or/and space restricted sensitivity analyses.

RESULTS

The whole data set included 15 592 cases and 2210 controls. With the primary approach (4797 cases and 1085 controls), OR was 3.64 (2181 cases) for subjects ever employed in construction. We found elevated risks for blue-collar occupations (1993 cases, OR 4.52), including bricklayers (988 cases, OR 7.05), general construction workers (320 cases, OR 4.66), plumbers and pipe fitters (305 cases, OR 9.13), painters (104 cases, OR 2.17) and several others. Sensitivity analyses yielded very similar findings. Using the secondary approach, we observed similar patterns, but ORs were remarkably lower.

CONCLUSIONS

We found markedly increased PM risks for most occupations in the construction industry. These findings are relevant for compensation of subjects affected with mesothelioma in the construction industry.