Estimating occupational disease burden: a way forward

Estimates of occupational disease burden provide important information on which effective policy and regulations can be developed. However, there is no direct way that these data can be obtained, and most burden estimates are derived by merging different data from diverse sources to synthesize estimates of the number of people made ill or who have died from workplace exposures. In recent years, several research groups have published estimates of occupational health burden at national or global scales; these are not always consistent. The World Health Organisation and the International Labour Organisation have taken on the task of producing occupational disease burden estimates for several workplace agents, which we assume are to be seen as the definitive global, regional, and national data. In this commentary, we critique the WHO/ILO approach for their estimates of the non-melanoma skin cancer burden from solar ultraviolet radiation and some of their results for hazardous particulates. We provide recommendations for researchers undertaking occupational burden estimates that they should report along with their data.

Cause specific mortality in an Italian pool of asbestos workers cohorts

BACKGROUND

Asbestos is a known human carcinogen and is causally associated with malignant mesothelioma, lung, larynx and ovarian cancers.

METHODS

Cancer risk was studied among a pool of formerly asbestos-exposed workers in Italy. Fifty-two Italian asbestos cohorts (asbestos-cement, rolling-stock, shipbuilding, and other) were pooled and their mortality follow-up was updated to 2018. Standardized mortality ratios (SMRs) were computed for major causes of death considering duration of exposure and time since first exposure (TSFE), using reference rates by region, age and calendar period.

RESULTS

The study included 63,502 subjects (57,156 men and 6346 women): 40% who were alive, 58% who died (cause known for 92%), and 2% lost to follow-up. Mortality was increased for all causes (SMR: men = 1.04, 95% confidence interval [CI] 1.03-1.05; women = 1.15, 95% CI 1.11-1.18), all malignancies (SMR: men = 1.21, 95% CI 1.18-1.23; women = 1.29, 95% CI 1.22-1.37), pleural and peritoneal malignancies (men: SMR = 10.46, 95% CI 9.86-11.09 and 4.29, 95% CI 3.66-5.00; women: SMR = 27.13, 95% CI 23.29-31.42 and 7.51, 95% CI 5.52-9.98), lung (SMR: men = 1.28, 95% CI 1.24-1.32; women = 1.26, 95% CI 1.02-1.53), and ovarian cancer (SMR = 1.42, 95% CI 1.08-1.84). Pleural cancer mortality increased during the first 40 years of TSFE (latency), reaching a plateau thereafter.

CONCLUSIONS

Analyses by time-dependent variables showed that the risk for pleural neoplasms increased with latency and no longer increases at long TSFE, consistent with with asbestos clearance from the lungs. Peritoneal neoplasm risk increased over all observation time.

Role of Nrf2 in 1,2-dichloropropane-induced cell proliferation and DNA damage in the mouse liver

1,2-Dichloropropane (1,2-DCP) is recognized as the causative chemical of occupational cholangiocarcinoma in printing workers in Japan. However, the cellular and molecular mechanisms of 1,2-DCP-induced carcinogenesis remains elusive. The present study investigated cellular proliferation, DNA damage, apoptosis, and expression of antioxidant and proinflammatory genes in the liver of mice exposed daily to 1,2-DCP for 5 weeks, and the role of nuclear factor erythroid 2-related factor 2 (Nrf2) in these responses. Wild-type and Nrf2-knockout (Nrf2-/-) mice were administered 1,2-DCP by gastric gavage, and then the livers were collected for analysis. Immunohistochemistry for BrdU or Ki67 and TUNEL assay revealed that exposure to 1,2-DCP dose-dependently increased proliferative cholangiocytes, whereas decreased apoptotic cholangiocytes in wild-type mice but not in Nrf2-/- mice. Western blot and quantitative real-time PCR showed that exposure to 1,2-DCP increased the levels of DNA double-strand break marker γ-H2AX and mRNA expression levels of NQO1, xCT, GSTM1, and G6PD in the livers of wild-type mice in a dose-dependent manner, but no such changes were noted in Nrf2-/- mice. 1,2-DCP increased glutathione levels in the liver of both the wild-type and Nrf2-/- mice, suggesting that an Nrf2-independent mechanism contributes to 1,2-DCP-induced increase in glutathione level. In conclusion, the study demonstrated that exposure to 1,2-DCP induced proliferation but reduced apoptosis in cholangiocytes, and induced double-strand DNA breaks and upregulation of antioxidant genes in the liver in an Nrf2-dependent manner. The study suggests a role of Nrf2 in 1,2-DCP-induced cell proliferation, antiapoptotic effect, and DNA damage, which are recognized as key characteristics of carcinogens.

Bladder cancer risk in relation to occupations held in a nationwide case-control study in Iran

Globally, bladder cancer has been identified as one of the most frequent occupational cancers, but our understanding of occupational bladder cancer risk in Iran is less advanced. This study aimed to assess the risk of bladder cancer in relation to occupation in Iran. We used the IROPICAN case-control study data including 717 incident cases and 3477 controls. We assessed the risk of bladder cancer in relation to ever working in major groups of the International Standard Classification of Occupations (ISCO-68) while controlling for cigarette smoking, opium consumption. Logistic regression models were used to estimate odds ratios (ORs) and 95% confidence intervals (CI). In men, decreased ORs for bladder cancer were observed in administrative and managerial workers (OR 0.4; CI: 0.2, 0.9), and clerks (OR 0.6; CI: 0.4, 0.9). Elevated ORs were observed in metal processors (OR 5.4; CI: 1.3, 23.4), and workers in occupations with likely exposure to aromatic amines (OR 2.2; CI: 1.2, 4.0). There was no evidence of interactions between working in aromatic amines-exposed occupations and tobacco smoking or opium use. Elevated risk of bladder cancer in men in metal processors and workers likely exposed to aromatic amines aligns with associations observed outside Iran. Other previously confirmed associations between high-risk occupations and bladder cancer were not observed, possibly due to small numbers or lack of details on exposure. Future epidemiological studies in Iran would benefit from the development of exposure assessment tools such as job exposure matrices, generally applicable for retrospective exposure assessment in epidemiological studies.

The Usefulness of an Online Simplified Screening Questionnaire (SSQ) in Identifying Work-Related Cancers

To obtain a history of occupational exposure in the workplace, the questionnaire is one of the main sources of information. The aim of this study was to develop an online questionnaire using the REDCap data management platform based on the Work-Related Cancer Surveillance Guidelines, reported by the Brazilian National Cancer Institute. Several issues were taken into consideration for its routine application. It should be simple, easy, capable of being applied in a short time and used in the clinical setting of collecting information on the occupational history of the cancer patient. Consequently, this could enable the compulsory notification of work-related cancer. The questionnaire was developed based on questions about the use of and exposure to carcinogenic factors at work and due to smoking. An entirely electronic version of the cancer patient interview was performed using tablets. The online questionnaire was applied at the Barretos Cancer Hospital, Barretos, to newly diagnosed patients from July 2016 to 2018. A total of 1063 patients were included, and 550 indicated positively when asked "Do you work, or have you worked with this substance and/or in this function?/job?" Of these potentially notified patients, 38 subsequently had compulsorily reported work-related cancer. Another important result of this study was the creation and development of a website. In conclusion, we developed an online tool that could facilitate hospital routines, contributing to generating data for the compulsory notification of work-related cancer and triggering investigations and surveillance actions in Brazil.

Environmental Exposure Assessment: Considerations for Oncology Nurses

Certain patients with cancer are eligible for exposure-related cancer compensation through federal programs, class action lawsuits, or employer programs. However, clinical tools for oncology nurses often do not include prompt.

Barriers and Facilitators in the Creation of a Surveillance System for Solar Radiation-Induced Skin Cancers

Outdoor workers are exposed to many hazards, including solar ultraviolet radiation (UVR). Identifying, reporting, analyzing and tracking the exposures or health outcomes of outdoor workers have not generally been formally considered. This article aims to summarize the best practices/strategies for creating an occupational sun exposure or skin cancer surveillance system for outdoor workers and to understand the key barriers and facilitators to the development of such a system. For the design of a successful occupational safety and health (OSH) surveillance system five occupational surveillance strategies are summarized: exposure registry, disease registry, disease screening/medical surveillance, sentinel event surveillance, and disease surveillance via data linkage. Ten key considerations are identified, including identifying a clear goal, a defined target population and stakeholder involvement, five critical barriers are highlighted including underreporting and funding, and five vital facilitators are recognized including communication/collaboration and a simple reporting process.

Occupational cancer illness in Brazil: an integrative literature review

The present study aimed to investigate data from the scientific literature on patterns of illness due to occupational cancer in Brazil. An integrative literature review was conducted in July 2020 and reviewed in June 2021, with no time restriction, using the Health Science Descriptors "Neoplasms," "Occupational Risks," "Occupational Cancer," and keywords related, which were searched on the following databases: Latin American Literature in Health Sciences, SciELO, PubMed, Scopus, Web of Science, and Cumulative Index to Nursing and Allied Health Literature. The search and selection flow followed that recommended by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Statement - 2020. Six manuscripts were selected, published from 1995 to 2019, which described occupational cancer affecting lung, oral cavity, pharynx and larynx, central nervous system, and skin. There was a time gap between the studies, and only the one involving lung cancer results on the most prevalent pattern of illness in the industrial sector, compared to the non-industrial. A shortage of scientific articles on patterns of illness was found. There was a predominance of scientific publications referring to occupational cancer illness related to the industrial sector compared to the number of publications directed to the primary and tertiary productive sectors. It is worth noting the constant need for research and epidemiological surveys to promote surveillance and protective actions aimed at occupational health.

Burden of occupational cancer in Brazil and federative units, 1990-2019

OBJECTIVE

To analyze the spatiotemporal distribution of the burden of occupational cancer in Brazil and federative units between 1990 and 2019.

METHODS

Data were extracted from the Global Burden of Disease (GBD) study. Deaths from cancer whose attributable risk factor was occupational carcinogens were considered. Spatial analysis was performed with the first and last years of the series (1990 and 2019). Age-adjusted mortality rates were used to estimate the global Moran's Index (Moran's I), and the local indicator of spatial association (LISA) to identify clusters in the country with the respective statistical significance. The occupational cancer mortality rate, adjusted for age, was analyzed based on its trend for Brazil and federative units, in the period between 1990 and 2019.

RESULTS

Between 1990 and 2019, occupational cancer mortality rate showed a decreasing trend (R2=0.62; p<0.001) as well as the burden of disease indicator - DALY (R2=0.84; p<0.001). However, mortality is increasing in most states, suggesting that a minority of federative units induce the country's global trend. There is also the development of a spatial pattern of autocorrelation, indicating clusters of states with low mortality and DALY rates in the Northeast and high values in the South of the country.

CONCLUSION

The overall decreasing trend in the trend of occupational cancer masks the heterogeneity across states. This scenario may be associated with the diversity of economic activities, and suggests a decentralized and equitable plan for occupational cancer surveillance.

Estimate of Occupational Exposure to Carcinogens among Migrant Workers in the United Arab Emirates: A Cross-Sectional Study

Occupational illnesses, such as cancer, cause more deaths each year than occupational accidents. Occupational carcinogens include physical, chemical, biological and organizational hazards. In the United Arab Emirates (UAE), migrant workers account for 80% of labor. Being sometimes employed as unskilled workers and more willing to work in demanding jobs, their vulnerability and exposure may be increased. This study aimed to estimate the prevalence of occupational exposure to workplace carcinogens among migrant workers in the UAE. A sample of employees working in construction, cleaning, dry cleaning, mechanic workshops and hair salons were recruited and interviewed. Using OccIDEAS (an online assessment tool), participants were asked questions about their demographics, work history and regular tasks. Exposure to various carcinogens was estimated using the in-built algorithms of OccIDEAS. A sample of 1778 workers was included. The sample consisted of workers from Bangladesh (19.2%), India (31%), Nepal (4.7%), Pakistan (29.9%) and the Philippines (4.8%), with the rest from other nationalities. Overall, the prevalence of probable exposure was considerable, with the highest among drivers (96%) and the lowest among laundry workers (52%). Moderate to high exposure was found to 20 different carcinogens. Self-rated health among those who were exposed to carcinogens was significantly lower than among those not exposed (AOR = 0.783, 95% CI [0.638-0.961]). Exposure to several different carcinogens is relatively common in the UAE among migrant workers. Further strengthening policies and the implementation of tailored interventions are needed to prevent exposure to occupational carcinogens and, consequently, to combat occupational cancer in the UAE.

Mesothelioma in situ with regressive malignant pleural effusion and an unexpected evolution: A case report

Malignant pleural mesothelioma (MPM) is an aggressive neoplasm that originates from hyperplasia and metaplasia of the mesothelial cells that cover the pleural cavity. Previous exposure to asbestos is the main risk factor. Since MPM is often diagnosed at an advanced stage with rapid evolution and resistance to treatment, it is associated with an unfavorable outcome. Mesothelioma in situ (MIS) has been postulated as a preinvasive phase of MPM; however, its diagnostic criteria have been defined only recently. Diagnosis of MIS may represent an opportunity for early therapies with better results, but the optimal approach has not been defined thus far. Here, we report on a case of a 74-year-old man with right-sided pleural effusion and a previous history of occupational exposure to asbestos for 9 years who was diagnosed with MIS after a latency of 36 years. During follow-up, spontaneous disease regression was observed 5 months after the initial diagnosis; however, it recurred in the form of invasive epithelioid MPM. There is a paucity of literature on MIS and its evolution; however, our case provides relevant knowledge of this unusual behavior, which is important to define follow-up and therapeutic strategies for future cases.

Perceptions of Work-Related Health and Cancer Risks Among Women Firefighters: A Qualitative Study

OBJECTIVES

We use a qualitative method to gain further insight into women firefighters' experiences, perceptions of cancer, health, and safety risks in the fire service.

METHODS

We conducted six focus groups with U.S. women firefighters. Participants engaged in a 60 to 75-minute, semi-structured discussion and completed a sociodemographic questionnaire. A qualitative descriptive approach was used to inductively create themes. Data collection concluded when saturation was met.

RESULTS

Forty-nine women firefighters participated. Qualitative results indicated the main health concerns include: occupational cancer risks including, risks related to hazardous exposures, sleep disruption and stress; and women's health concerns including, cancer, pregnancy and breastfeeding, and lack of resources.

CONCLUSIONS

Women firefighters are concerned about their risk for cancer due to their occupation and identify a lack of resources specific to health and safety needs of women firefighters.

Exposures to IARC Carcinogenic Agents in Work Settings Not Traditionally Associated with Sinonasal Cancer Risk: The Experience of the Italian National Sinonasal Cancer Registry

The aim of this study is to highlight tasks and jobs not commonly considered at high risk for sinonasal cancer (SNC) identified by Regional Operating Centers currently active in the Italian National Sinonasal Cancer Registry (ReNaTuNS), which retrieve occupational histories through a standardized questionnaire. Data on exposures to IARC carcinogenic agents in work settings unknown to be associated with SNC risk were collected and analyzed. Out of 2,208 SNC cases recorded in the ReNaTuNS database, 216 cases and their worked exposure periods were analyzed. Unsuspected jobs with exposure to wood dust include construction-related tasks, production of resins, agriculture and livestock jobs (straw and sawdust), and heel factory work (cork dust). Other examples are hairdressers, bakers (formaldehyde), dressmakers, technical assistants, wool and artificial fiber spinners, and upholsterers (textile dusts). Moreover, settings with coexposure to different agents (e.g., wood with leather dusts and chromium–nickel compounds) were recognized. The study describes jobs where the existence of carcinogenic agents associated with SNC risk is unexpected or not resulting among primary materials employed. The systematic epidemiological surveillance of all epithelial SNC cases with a detailed collection of their work history, as performed by a dedicated population registry, is essential for detecting all potential occupational cases and should be considered in the context of forensic medicine and the compensation process.

[Coverage of issues of professional malignant neoplasms of the respiratory tract in modern clinical guidelines of the Ministry of Health of Russia]

OBJECTIVE

Analysis and comparison of clinical guidelines (CG) on malignant neoplasms of the respiratory system, placed in the CG rubricator of the Ministry of Health of Russia, for the information they contain on the role of factors and working conditions of the working environment in the etiology of respiratory diseases, including the upper respiratory tract, and comparison this information with published and regularly updated data from the International Agency for Research on Cancer (IARC).

MATERIAL AND METHODS

Clinical recommendations from the heading of the Ministry of Health of Russia "Cancer of the laryngopharynx", "Cancer of the nasopharynx", "Cancer of the oropharynx", "Cancer of the nasal cavity and paranasal sinuses", "Cancer of the larynx", "Cancer of the trachea", "Cancer of the lung", and IARC data according to the List of Classifications by cancer sites with sufficient or limited evidence in humans dated 11/29/2019.

RESULTS

The low level of registration of occupational cancer of the upper respiratory tract in Russia is due to an inadequate system of criteria for detecting this form of occupational pathology, a long latency period of diseases, and insufficient assessment of the history of information on the potential role of occupational carcinogens. The CGs developed to optimize the diagnosis and treatment of malignant neoplasms of the respiratory system do not contain up-to-date information on the role of professional potential carcinogens in the genesis of malignant neoplasms.

CONCLUSION

Recognition of the professional nature of malignant neoplasms of the respiratory system implies, firstly, strengthening the role of otorhinolaryngologists in early diagnosis and rehabilitation of patients, and secondly, it has a pronounced preventive focus in the form of tasks facing the employer to reduce the carcinogenic load and develop preventive measures aimed to reduce and prevent the development of malignant tumors in workers, including the respiratory system.

Increased Risk of Gastric Cancer in Asbestos-Exposed Workers: A Retrospective Cohort Study Based on Taiwan Cancer Registry 1980-2015

Asbestos has been recognized as a human carcinogen associated with malignant mesothelioma, cancers of lung, larynx, and ovary. However, a putative association between gastric cancer and asbestos exposure remains controversial. In this study, we aimed to explore gastric cancer risk of workers potentially exposed to asbestos in Taiwan. The asbestos occupational cohort was established from 1950 to 2015 based on the Taiwan Labor Insurance Database, and Taiwan Environmental Protection Agency regulatory datasets, followed by the Taiwan Cancer Registry for the period 1980–2015. Standardized incidence ratios (SIRs) for cancer were computed for the whole cohort using reference rates of the general population, and also reference labor population. Compared with the general population, SIR of the asbestos occupational cohort for the gastric cancer increased both in males (1.05, 95% confidence interval (CI): 1.02–1.09) and females (1.10, 95% CI: 1.01–1.18). A total of 123 worksites were identified to have cases of malignant mesothelioma, where increased risk for gastric cancer was found with a relative risk of 1.76 (95% CI: 1.63–1.90). This 35-year retrospective cohort study of asbestos-exposed workers in Taiwan may provide support for an association between occupational exposure to asbestos and gastric cancer.

Development of Korean CARcinogen EXposure: An Initiative of the Occupational Carcinogen Surveillance System in Korea

OBJECTIVE

To prevent occupational cancers, carcinogen exposure surveillance systems have been developed in many countries. This study aimed to develop a carcinogen exposure database specific to South Korea.

METHODS

Twenty known human carcinogens were selected for this study. The International Standard Classification of Industry was used for a classification scheme of industries. Three nationwide occupational exposure databases, the Work Environment Measurement Database, the Special Health Examination Database, and the Work Environment Condition Survey, were used to calculate reference exposure prevalence estimates by carcinogen and industry. Then, 37 professional industrial hygienists with at least 19 years of field experience provided their own exposure prevalence estimates, after reviewing the abovementioned reference estimates derived from three data sources. The median value of the experts' estimates was used as the final exposure prevalence. Finally, the number of exposed workers was computed by multiplying the final exposure prevalence by the number of workers extracted from the 2010 national census data by carcinogen and industry.

RESULTS

The exposure prevalence and the number of exposed workers were calculated according to 20 carcinogen and 228 minor industrial groups, assuming year 2010 circumstances. The largest population was exposed to welding fumes (326 822 workers), followed by ultraviolet radiation (238 937 workers), ionizing radiation (168 712 workers), and mineral oil mist (146 798 workers).

CONCLUSIONS

Our results provide critical data on carcinogen exposure for the prevention of occupational cancers.

How the Intensity of Night Shift Work Affects Breast Cancer Risk

Background-In 2019, the IARC concluded that "night shift work is probably carcinogenic to humans (Group 2A), based on limited evidence from human epidemiological studies and sufficient evidence of cancer and strong mechanistic evidence in experimental Animals." The negative health consequences of night shift work may depend on how the night shifts are scheduled. The aim of this study was to investigate how the characteristics of night work affect the risk of developing breast cancer. Methods-A case-control study was conducted in 2015-2019 in the Lodz region. The case group included 494 women with breast cancer, while the control group included 515 healthy women. Results-Night work was found to be the third most important factor regarding breast cancer after a high BMI and a short or no breastfeeding period and before factors such as early menstruation, late menopause, no pregnancy, and smoking. The harmful effects of night work were influenced by its intensity, frequency, rotation, and the number of night shift years worked. Night work increases the breast cancer risk by 2.34 times, and high-intensity night work increases the breast cancer risk by 2.66 times. Conclusions-Appropriate ergonomic recommendations for night shift work for employers should be considered.

[Occupational risk related to natural optical radiation exposure and skin cancers]

Skin tumors are the most frequent neoplasms worldwide in Caucasian subjects, and UV exposure is one of the most relevant risk factors in their etiology. Cumulative UV exposure is strongly associated with an increased occurrence of both basal and squamous cell carcinomas (i.e. Non melanoma skin cancers - NMSC), while for malignant melanoma the role of UV radiation as risk factors seems more related to intermittent and intense exposures, able to induce repeated sunburns, at young ages. Considering the occupational risk, currently UV radiation, part of the solar radiation (SR) spectrum, is one of the major risks in all jobs including outdoor activities (outdoor work - OW): many studies show high levels of solar UV exposure during OW, nevertheless to date the European, and Italian, legislation on occupational risks prevention does not include specific requirements for SR compleexposure at work, as occupational exposure limits values or workers' health surveillance. This is not coherent with the strong associations showed in scientific literature in particular between the occurrence of NMSC and a history of OW. Accordingly, considering the high exposure levels, the large number of outdoor workers and the strong associations with NMSC, we'd expect a relevant number of occupational skin cancers (OSC) to be reported every year to the national workers' compensation authorities in European countries. Nevertheless, in Italy, as in other European countries, the number of reported UV-induced OSC is much lower than the expected number of OSC, with less than 40 cases reported on average in Italy in last years compared to about a thousand of expected cases incident in outdoor workers per year. An increasing in the reporting of OSC would certainly be important, for the purpose of a better recognition of the real dimension of the phenomenon, and to stimulate the implementation of adequate preventive strategies, in order to guarantee an improved protection of outdoor workers and a more appropriate prevention of the adverse health effects related to solar UV exposure.

A Potential Link Between Prolonged Cork Exposure and Intestinal-Type Sinonasal Adenocarcinoma - Special Findings of a Retrospective Cohort Analysis

Introduction

intestinal-type sinonasal adenocarcinoma (ITAC) is a rare epithelium tumor of the nasal cavities and paranasal sinuses. Exposure to wood and leather dusts is a strong etiological factor related to its development. Prolonged cork exposure has rarely been associated.

Materials and Methods

thirty-seven-year (1981–2018) retrospective cohort analysis of all consecutive patients with sinonasal cancer (SNC) followed at our institution. Medical records were reviewed to determine patient demographics, occupational/environmental exposure, location and extent of the tumor, stage, histopathology findings, treatment strategies, and oncologic outcomes. Survival analysis was done using Kaplan–Meier method.

Results

we evaluated 379 patients with SNC, including 39 (10.3%) ITAC. Patient median age was 73 years (range 49–87), 56% male and 69% with identified professional occupational exposure (54% for cork; 69.2% considering only those for which an agent has been identified). Seventy-two percent had locally advanced disease (stage III or IVA–B). The initial treatment was surgery in 77%, and 54% received adjuvant radiotherapy. The median time to progression, progression-free survival, and overall-survival was 2.36 years (95% CI 1.54–8.70), 1.96 years (95% CI 1.43–3.74), and 3.51 years (95% CI 2.33–10.02), respectively.

Conclusion

ITAC is an uncommon malignancy that grows silently, which contributes to delayed diagnosis, advanced stage and low survival rates. In our cohort, we observed a high prevalence of cork occupational exposure. This finding may lead to the implementation of protection measures and suggest a potential link to be further studied.

Strategic Task and Break Timing to Reduce Ultraviolet Radiation Exposure in Outdoor Workers

Objectives: Public health messaging about sun avoidance strategies is often not practical for outdoor workers. The objective of this study was to use personal monitoring data to determine when peak UVR exposure occurs for outdoor workers, estimate how much UVR could be reduced by altering the timing of shady tasks or breaks during peak exposure times, and descriptively compare these to peak periods of ambient UVR. Ultimately, we aim to provide evidence-based sun avoidance recommendations for outdoor workers in British Columbia, Canada. Methods: UVR exposure data [standard erythemal dose (SED)] were collected during the 2013 summer months in Vancouver, using personal electronic dosimeters that sampled once per minute for an average of 4.4 working days (range: 1-7 days). Mixed-effect models were used to estimate the 60-, 30-, and 15-min time intervals at which maximum exposure occurred for the months of July and August. Using these time intervals, UVR exposure during peak periods was summarized as SED and as a percentage of the total daily exposure. Ambient UVR was also collected using data from the nearest Brewer spectrophotometer station and parallel analyses were conducted. Results: There were 73 workers and 321 participant-days available for analysis. Models indicated that periods of maximum exposure for 15-, 30-, and 60-min intervals began at 12:28, 12:17 pm, and 11:52 am, respectively, for sunny days in July. These periods were similar in August. The median exposure during these time periods and the potential for reducing UVR was 0.03 SED (2.8% potential daily exposure reduction), 0.09 SED (7.1%), and 0.18 SED (15.9%), respectively. However, there was a large range in exposure estimates as some workers experienced up to 84.8% of their exposure in the peak 60-min interval. Conclusion: Skin cancer prevention messaging does not include practical messages for outdoor workers and providing times of peak UVR help to identify times when the greatest reductions in exposure can occur. Prevention measures including shady breaks, increased sun protection, and task reorganization during these peak times are recommended during these peak times to reduce UVR exposure among those at highest risk.

A scoping review to identify strategies that work to prevent four important occupational diseases

BACKGROUND

Despite being largely preventable, many occupational diseases continue to be highly prevalent and extremely costly. Effective strategies are required to reduce their human, economic, and social impacts.

METHODS

To better understand which approaches are most likely to lead to progress in preventing noise-related hearing loss, occupational contact dermatitis, occupational cancers, and occupational asthma, we undertook a scoping review and consulted with a number of key informants.

RESULTS

We examined a total of 404 articles and found that various types of interventions are reported to contribute to occupational disease prevention but each has its limitations and each is often insufficient on its own. Our principal findings included: legislation and regulations can be an effective means of primary prevention, but their impact depends on both the nature of the regulations and the degree of enforcement; measures across the hierarchy of controls can reduce the risk of some of these diseases and reduce exposures; monitoring, surveillance, and screening are effective prevention tools and for evaluating the impact of legislative/policy change; the effect of education and training is context-dependent and influenced by the manner of delivery; and, multifaceted interventions are often more effective than ones consisting of a single activity.

CONCLUSIONS

This scoping review identifies occupational disease prevention strategies worthy of further exploration by decisionmakers and stakeholders and of future systematic evaluation by researchers. It also identified important gaps, including a lack of studies of precarious workers and the need for more studies that rigorously evaluate the effectiveness of interventions.

High-priority carcinogenic occupational agents and activities for health surveillance in Brazil

The aims of the present study were to assemble a list of carcinogens considered as having high priority for occupational health actions in Brazil and to describe the process followed to validate it. Through a literature review we retrieved the main carcinogens used in production activities in Brazil, the carcinogenicity classification developed by the International Agency for Research on Cancer (IARC) and corresponding types of cancer relevant within the Brazilian context. The list thus assembled was reviewed and validated by an expert panel. It includes known and suspected carcinogens found in the production process of some industries in Brazil, and might serve as orientation for future studies on the burden of occupational cancer.

The Riga-European Association of Schools of Occupational Medicine (EASOM) Statement on Work-Related Cancer

Reducing the burden of occupational cancers (OCs) is currently one of the most challenging Occupational Health (OH) issues. The European Union (EU) has made efforts to improve the existing legal framework and developed specific legislation aimed at reducing the burden of OC. However, available data suggest that OC are underreported. In August 2019, the European Association of Schools of Occupational Medicine (EASOM) adopted a statement that highlighted the importance of improving the education and training of Medical Doctors (MDs) to facilitate improvements in recognizing and reporting OC. To achieve this, EASOM proposes to promote OH education and training of MDs at undergraduate and postgraduate levels, foster harmonization of OH education and teaching standards and programs across EU countries, and enhance cooperation between universities and international scientific associations. Finally, we suggest that occupational data should be recorded in cancer and medical registers. By engaging MDs more fully in the debate about OCs, they will become more aware of the Occupational Physician’s role in reducing the burden of OCs and, furthermore, embed consideration of occupation as a potential cause of cancer into their own practice. These interventions will help promote the implementation of policies and interventions aimed to reduce OC in the workplace.

Estimation of Occupational Exposure to Asbestos in Italy by the Linkage of Mesothelioma Registry (ReNaM) and National Insurance Archives. Methodology and Results

The identification and monitoring of occupational cancer is an important aspect of occupational health protection. The Italian law on the protection of workers (D. Leg. 81/2008) includes different cancer monitoring systems for high and low etiologic fraction tumors. Record linkage between cancer registries and administrative data is a convenient procedure for occupational cancer monitoring. We aim to: (i) Create a list of industries with asbestos exposure and (ii) identify cancer cases who worked in these industries. The Italian National Mesothelioma Registry (ReNaM) includes information on occupational asbestos exposure of malignant mesothelioma (MM) cases. We developed using data from seven Italian regions a methodology for listing the industries with potential exposure to asbestos linking ReNaM to Italian National Social Security Institute (INPS) data. The methodology is iterative and adjusts for imprecision and inaccuracy in reporting firm names at interview. The list of asbestos exposing firms was applied to the list of cancer cases (all types associated or possibly associated with asbestos according to International Agency for Research on Cancer (IARC) monograph 100C) in two Italian regions for the indication of possible asbestos exposure. Eighteen percent of the cancer cases showed at least one work period in firms potentially exposing to asbestos, 48% of which in regions different from where the cases lived at diagnosis. The methodology offers support for the preliminary screening of asbestos exposing firms in the occupational history of cancer cases.

Chrysotile fibers in tissue adjacent to laryngeal squamous cell carcinoma in cases with a history of occupational asbestos exposure

Asbestos describes a group of naturally occurring fibrous silicate mineral compounds that have been associated with a number of respiratory maladies, including mesothelioma and lung cancer. In addition, based primarily on epidemiologic studies, asbestos has been implicated as a risk factor for laryngeal and pharyngeal squamous cell carcinoma (SCC). The main objective of this work was to strengthen existing evidence via empirical demonstration of persistent asbestos fibers embedded in the tissue surrounding laryngeal and pharyngeal SCC, thus providing a more definitive biological link between exposure and disease. Six human papillomavirus (HPV)-negative laryngeal (n = 4) and pharyngeal (n = 2) SCC cases with a history working in an asbestos-exposed occupation were selected from a large population-based case-control study of head and neck cancer. A laryngeal SCC case with no history of occupational asbestos exposure was included as a control. Tissue cores were obtained from adjacent nonneoplastic tissue in tumor blocks from the initial primary tumor resection, and mineral fiber analysis was performed using a scanning electron microscope equipped with an energy dispersive X-ray analyzer (EDXA). Chrysotile asbestos fiber bundles were identified in 3/6 of evaluated cases with a history of occupational asbestos exposure. All three cases had tumors originating in the larynx. In addition, a wollastonite fiber of unclear significance was identified one of the HPV-negative pharyngeal SCC cases. No mineral fibers were identified in adjacent tissue of the case without occupational exposure. The presence of asbestos fibers in the epithelial tissue surrounding laryngeal SCC in cases with a history of occupational asbestos exposure adds a key line of physical evidence implicating asbestos as an etiologic factor.

The impact of night shift work on breast cancer: Results from the Burden of Occupational Cancer in Canada Study

BACKGROUND

We estimated the proportion and number of female breast cancer cases in Canada attributable to night shift work, a probable cause of breast cancer.

METHODS

Levin's equation was used to calculate population attributable fractions (PAFs) among Canadian women who ever worked night/rotating shifts from 1961 to 2000, accounting for labor turnover and survival to the year 2011. The calculated PAFs were applied to 2011 Canadian breast cancer incidence statistics to obtain the number of attributable cases.

RESULTS

Approximately 1.5 million women ever worked night/rotating shifts during 1961-2000 and survived to 2011. The PAFs ranged from 2.0% (95% confidence interval [CI]: 1.4-6.2) to 5.2% (95% CI: 3.7-13.6), and 470 to 1200 incident breast cancer cases in 2011 were likely due to shift work, of which 38% would have been diagnosed among women in health-related occupations.

CONCLUSIONS

More research is needed to increase the certainty of this association, but current evidence supports workplace-based prevention.

[The "new carcinogens' directive" from the European Union: new tasks waiting for us, new opportunities in front of us (and that we need not to waste) in Italy]

The new EU directive on the protection of workers from the risks related to exposure to carcinogens and mutagens at work, issued on December 2017, will be integrated inside the Member States' national laws not later than 17th January 2020. The new directive brings in force new binding occupational exposure limit values (BOELVs) for several agents, some of great importance such as hard wood dusts, a set of hexavalent chromium compounds and crystalline silica dust; for some cases, the entry into force of the new limits is delayed in time. The new directive clarifies that the limit values are established considering factors distinct from health necessities too. The Member States are bound to adopt national limit values not avexceeding the corresponding EU ones, but are empowered to lower them. It is essential that the control of the actual respect of the limit values results not only from the application of theoretic previsional models, but is entrusted mainly to high quality exposure measurements and to estimates directly derived from measurements, on the base of publicly available JEMs. The specific health surveillance to be provided to any person both exposed and previously exposed to carcinogens at work should not be limited to proper oncological screening actions, but should include programs for biological monitoring of both exposures and related pre-neoplastic effects, every time any of these is possible and useful. A fair mapping of the exposures to carcinogens and mutagens at work and a systematical registration of cases of cancers attributable to occupational exposures will be placed side to side.

Clustering of malignant pleural mesothelioma in asbestos factories: a subgroup analysis in a 29-year follow-up study to identify high-risk industries in Taiwan

OBJECTIVE

Exposure to asbestos is the major cause for malignant pleural mesothelioma (MPM), but the causal link of individual cases is difficult to establish for lack of exposure information and long disease latency.

METHODS

We established a retrospective cohort of workers employed in asbestos industries during the period of 1950-1989 and the occurrence of MPM during the period of 1980-2009 was examined with the Taiwan Cancer Registry. Estimated rate ratios (eRRs) were computed for each factory where any case of MPM was diagnosed by assuming Poisson distribution with a minimal latency of 20 years.

RESULTS

A total of 18 MPM (17 males, 1 female) in eight factories were found. The incidence rate of MPM for the eight factories was 18.0 per million, ranging from 6.2 per million (military factory) to 268.2 per million (asbestos cement). We observed significantly increased risks for MPM in asbestos cement, thermal insulation and shipbuilding industries, with eRR (genders combined) of 113.6, 87.5 and 15.8, respectively. The sensitivity analyses considering latency showed similar findings in latency ≥30 years, and the shipbuilding industry presented a significant eRR given a latency ≥40 years. The gender-specific eRR showed similar results in men, but high eRR of 729.6 was observed in an asbestos cement factory where a female MPM was diagnosed.

CONCLUSIONS

This nationwide study in Taiwan comprehensively shows that different asbestos manufacturing processes, including asbestos cement, thermal insulation and shipbuilding industries, were at significantly increased risks for MPM. We recommend to establish a medical screening programme for workers previously exposed to asbestos to identify MPM and other asbestos-related diseases at an earlier stage.

From awareness to action: Sudbury, mining and occupational disease in a time of change

BACKGROUND:

Miners work in highly hazardous environments, but surprisingly, there are more fatalities from occupational diseases, including cancers, than from fatalities from injuries. Over the last few decades, the mining environment has become safer with fewer injuries and less exposure to the toxins that lead to occupational disease. There have been improvements in working conditions, and a reduction in the number of workers exposed, together with an overall improvement in the health of miners.

OBJECTIVES:

This study attempted to gain a deeper understanding of the impetus for change to reduce occupational exposures or toxins at the industry level. It focuses on one mining community in Sudbury, Ontario, with a high cancer rate, and its reduction in occupational exposures. It explored the level of awareness of occupational exposures from the perspective of industry and worker representatives in some of the deepest mines in the world. Although awareness may be necessary, it is often not a sufficient impetus for change, and it is this gap between awareness and change that this study explored. It examined the awareness of occupational disease as an impetus to reducing toxic exposures in the mining sector, and explores other forces of change at the industrial and global levels that have led to an impact on occupational exposures in mining.

METHODS:

From 2014 and 2016, 60 interviews were conducted with individuals who were part of, or witness to the changes in mining in Sudbury. From these, 12 labour and 10 industry interviews and four focus groups were chosen for further analysis to gain a deeper understanding of industry and labour’s views on the changes in mining and the impact on miners’ health from occupational exposures. The results from this subsection of the data is the focus for this paper.

RESULTS:

The themes that emerged told a story about Sudbury. There is awareness of occupational exposures, but this awareness is dwarfed in comparison to the attention that is given to the tragic fatal injuries from injuries and accidents. The mines are now owned by foreign multinationals with a change from an engaged, albeit paternalistic sense of responsibility for the health of the miners, to a less responsive or sympathetic workplace culture. Modernization has led to the elimination, substitution, or reduction of some of the worst toxins, and hence present-day miners are less exposed to hazards that lead to occupational disease than they were in the past. However, modernization and the drop in the price of nickel has also led to a precipitous reduction in the number of unionized miners, a decline in union power, a decline in the monitoring of present-day exposures, and an increase in non-unionized contract workers. The impact has been that miners have lost their solidarity and power to investigate, monitor or object to present-day exposures.

CONCLUSIONS:

Although an increase in the awareness of occupational hazards has made a contribution to the reduction in occupational exposures, the improvement in health of miners may be considered more as a “collateral benefit” of the changes in the mining sector. Multiple forces at the industrial and global level have differentially led to an improvement in the working and living environment. However, with the loss of union power, the miners have lost their major advocate for miner health.

Biomarkers for Early Diagnosis and Prognosis of Malignant Pleural Mesothelioma: The Quest Goes on

Malignant pleural mesothelioma (MM) is a highly aggressive tumor characterized by a poor prognosis. Although its carcinogenesis mechanism has not been strictly understood, about 80% of MM can be attributed to occupational and/or environmental exposure to asbestos fibers. The identification of non-invasive molecular markers for an early diagnosis of MM has been the subject of several studies aimed at diagnosing the disease at an early stage. The most studied biomarker is mesothelin, characterized by a good specificity, but it has low sensitivity, especially for non-epithelioid MM. Other protein markers are Fibulin-3 and osteopontin which have not, however, showed a superior diagnostic performance. Recently, interesting results have been reported for the HMGB1 protein in a small but limited series. An increase in channel proteins involved in water transport, aquaporins, have been identified as positive prognostic factors in MM, high levels of expression of aquaporins in tumor cells predict an increase in survival. MicroRNAs and protein panels are among the new indicators of interest. None of the markers available today are sufficiently reliable to be used in the surveillance of subjects exposed to asbestos or in the early detection of MM. Our aim is to give a detailed account of biomarkers available for MM.

The economic burden of occupational non-melanoma skin cancer due to solar radiation

Solar ultraviolet (UV) radiation is the second most prevalent carcinogenic exposure in Canada and is similarly important in other countries with large Caucasian populations. The objective of this article was to estimate the economic burden associated with newly diagnosed non-melanoma skin cancers (NMSCs) attributable to occupational solar radiation exposure. Key cost categories considered were direct costs (healthcare costs, out-of-pocket costs (OOPCs), and informal caregiver costs); indirect costs (productivity/output costs and home production costs); and intangible costs (monetary value of the loss of health-related quality of life (HRQoL)). To generate the burden estimates, we used secondary data from multiple sources applied to computational methods developed from an extensive review of the literature. An estimated 2,846 (5.3%) of the 53,696 newly diagnosed cases of basal cell carcinoma (BCC) and 1,710 (9.2%) of the 18,549 newly diagnosed cases of squamous cell carcinoma (SCC) in 2011 in Canada were attributable to occupational solar radiation exposure. The combined total for direct and indirect costs of occupational NMSC cases is $28.9 million ($15.9 million for BCC and $13.0 million for SCC), and for intangible costs is $5.7 million ($0.6 million for BCC and $5.1 million for SCC). On a per-case basis, the total costs are $5,670 for BCC and $10,555 for SCC. The higher per-case cost for SCC is largely a result of a lower survival rate, and hence higher indirect and intangible costs. Our estimates can be used to raise awareness of occupational solar UV exposure as an important causal factor in NMSCs and can highlight the importance of occupational BCC and SCC among other occupational cancers.

Italian pool of asbestos workers cohorts: mortality trends of asbestos-related neoplasms after long time since first exposure

OBJECTIVE

Asbestos is a known human carcinogen, with evidence for malignant mesothelioma (MM), cancers of lung, ovary, larynx and possibly other organs. MM rates are predicted to increase with a power of time since first exposure (TSFE), but the possible long-term attenuation of the trend is debated. The asbestos ban enforced in Italy in 1992 gives an opportunity to measure long-term cancer risk in formerly exposed workers.

METHODS

Pool of 43 previously studied Italian asbestos cohorts (asbestos cement, rolling stock, shipbuilding), with mortality follow-up updated to 2010. SMRs were computed for the 1970â€"2010 period, for the major causes, with consideration of duration and TSFE, using reference rates by age, sex, region and calendar period.

RESULTS

The study included 51 801 subjects (5741 women): 55.9% alive, 42.6% died (cause known for 95%) and 1.5% lost to follow-up. Mortality was significantly increased for all deaths (SMR: men: 1.05, 95% CI 1.03 to 1.06; women: 1.17, 95% CI to 1.12 to 1.22), all malignancies combined (SMR: men: 1.17, 95% CI to 1.14 to 1.20; women: 1.33, 95% CI 1.24 to 1.43), pleural and peritoneal malignancies (SMR: men: 13.28 and 4.77, 95% CI 12.24 to 14.37 and 4.00 to 5.64; women: 28.44 and 6.75, 95% CI 23.83 to 33.69 and 4.70 to 9.39), lung (SMR: men: 1.26, 95% CI 1.21 to 1.31; women: 1.43, 95% CI 1.13 to 1.78) and ovarian cancer (SMR=1.38, 95% CI 1.00 to 1.87) and asbestosis (SMR: men: 300.7, 95% CI 270.7 to 333.2; women: 389.6, 95% CI 290.1 to 512.3). Pleural cancer rate increased during the first 40 years of TSFE and reached a plateau after.

DISCUSSION

The study confirmed the increased risk for cancer of the lung, ovary, pleura and peritoneum but not of the larynx and the digestive tract. Pleural cancer mortality reached a plateau at long TSFE, coherently with recent reports.

Renal cell carcinoma and malignant peritoneal mesothelioma after occupational asbestos exposure: case report

Asbestos is the main causal factor for malignant mesothelioma (MM), a relatively rare and aggressive malignancy. Some epidemiological evidence suggests a role of this agent also in the etiology of renal cell carcinoma (RCC), the most common form of kidney cancer.

CASE REPORT

After 7 years of asbestos exposure, a 76-year-old asbestos-cement worker came to our notice with left flank pain. Diagnostic imaging disclosed a neoplasm in the upper two thirds of the left kidney, without evidence of metastases. After surgery (nephrectomy with para-aortic lymphadenectomy), histopathology revealed clear cell RCC. One year later, the patient was hospitalized for abdominal pain. Laparoscopy showed diffuse neoplastic infiltration of the peritoneum and liver. Histological and immunohistochemical examination of the bioptic samples led to the diagnosis of biphasic MM. The subject died 2 months later. Autopsy disclosed ascites and diffuse infiltration of the abdominal wall and viscera, without evidence of RCC relapse.

CONCLUSIONS

This is the second reported case of association between RCC and peritoneal MM in the scientific literature. Asbestos might be involved in the causation of both malignancies.

Workplace exposure to diesel and gasoline engine exhausts and the risk of colorectal cancer in Canadian men

BACKGROUND

The International Agency for Research on Cancer (IARC) classified diesel exhaust as carcinogenic to humans (Group 1) and gasoline exhaust as a possible carcinogen (Group 2B) based studies of lung cancer, however the evidence for other sites is limited. We addressed this question by investigating exposure to diesel and gasoline emissions with respect to risk of colorectal cancer in men.

METHODS

We used data from a population-based case-control study with incident cases of colon (n = 931) and rectal (n = 840) cancer and 1360 controls from 7 Canadian provinces conducted in 1994-1997. Lifetime occupational history and information on other risk factors was collected. Occupational hygienists, blinded to case-control status, assigned exposures to each job for 3 dimensions: concentration, frequency, and reliability. Logistic regression was used to estimate odds ratios (OR) and their 95 % confidence intervals (CI), adjusted for age, province, use of proxy respondents, smoking, body-mass index, physical activity, intake of alcohol, processed meats, and occupational exposure to asbestos and aromatic amines.

RESULTS

Among CRC cases, 638 (36 %) were exposed to diesel and 814 (46 %) were exposed to gasoline emissions. Relative to the unexposed, elevated risks were observed among subjects ever exposed to high concentration levels of diesel emissions for colorectal cancer (OR = 1.65, 95 % CI = 0.98-2.80) and rectal cancer (OR = 1.98, 95 % CI = 1.09-3.60), but not colon cancer. Prolonged (>10 years) exposure at high concentrations was also associated with high risks of rectal cancer (OR = 2.33 95 % CI = 0.94-5.78; p-trend = 0.02). No statistically significant associations were observed for gasoline emissions.

CONCLUSIONS

Our findings suggest that sustained high-level exposure diesel emissions may increase the risk of rectal cancer.

Bladder cancer and occupational exposure to diesel and gasoline engine emissions among Canadian men

The International Agency for Research on Cancer has classified diesel exhaust as a carcinogen based on lung cancer evidence; however, few studies have investigated the effect of engine emissions on bladder cancer. The purpose of this study was to investigate the association between occupational exposure to diesel and gasoline emissions and bladder cancer in men using data from the Canadian National Enhanced Cancer Surveillance System; a population‐based case–control study. This analysis included 658 bladder cancer cases and 1360 controls with information on lifetime occupational histories and a large number of possible cancer risk factors. A job‐exposure matrix for engine emissions was supplemented by expert review to assign values for each job across three dimensions of exposure: concentration, frequency, and reliability. Odds ratios (OR) and their corresponding 95% confidence intervals were estimated using logistic regression. Relative to unexposed, men ever exposed to high concentrations of diesel emissions were at an increased risk of bladder cancer (OR = 1.64, 0.87–3.08), but this result was not significant, and those with >10 years of exposure to diesel emissions at high concentrations had a greater than twofold increase in risk (OR = 2.45, 1.04–5.74). Increased risk of bladder cancer was also observed with >30% of work time exposed to gasoline engine emissions (OR = 1.59, 1.04–2.43) relative to the unexposed, but only among men that had never been exposed to diesel emissions. Taken together, our findings support the hypothesis that exposure to high concentrations of diesel engine emissions may increase the risk of bladder cancer.

From Awareness to Action: The Community of Sarnia Mobilizes to Protect its Workers from Occupational Disease

An exploratory qualitative case study investigated how different sectors of a highly industrialized community mobilized in the 1990s to help workers exposed to asbestos. For this study, thirty key informants including representatives from industry, workers, the community, and local politicians participated in semi-structured interviews and focus groups. The analysis was framed by a "Dimensions of Community Change" model. The informants highlighted the importance of raising awareness, and the need for leadership, social and organizational networks, acquiring skills and resources, individual and community power, holding shared values and beliefs, and perseverance. We found that improvements in occupational health and safety came from persistently communicating a clearly defined issue ("asbestos exposure causes cancer") and having an engaged community that collaborated with union leadership. Notable successes included stronger occupational health services, a support group for workers and widows, the fast-tracking of compensation for workers exposed to asbestos, and a reduction in hazardous emissions.

Modified nucleosides as biomarkers for early cancer diagnose in exposed populations

There is increasing worldwide interest in developing of markers for tumor diagnosis and identification of individuals who are at high cancer risk. Cancer, like other diseases accompanied by metabolic disorders, causes characteristic effects on cell turnover rate, activity of modifying enzymes, and RNA/DNA modifications. This results in an increased excretion of modified nucleosides in cancer patients. Therefore, for many years modified nucleosides have been suggested as tumor markers. The aim of the study was to elucidate further the usefulness of urinary nucleosides as possible markers at early detection of cancer in persons which are exposed against tumor promoting influences during their working life. Uranium miners are exposed to many kinds of pollutants that can cause health damage even lead to carcinogenesis. We analyzed modified nucleosides in urine samples from 92 miners who are at high risk for lung cancer to assess the levels of nucleosides by a multilayer perceptron (MLP) classifier - a neural network model. Eighteen nucleosides/metabolites were detected with reversed-phase high-pressure liquid chromatography (RP-HPLC). A valid set of urinary metabolites were selected and multivariate statistical technique of multilayer perceptron neural network were applied. In a previous study, MLP shows a sensitivity and specificity of 97 and 85%, respectively. MLP classification including the most relevant markers/nucleosides clearly demonstrates the elevation of RNA metabolism in miners, which is associated with possible malignant disease. We found that there were 30 subjects with early health disorders among 92 uranium workers based on MLP technique using modified nucleosides. The combination of RP-HPLC analysis of modified nucleosides and subsequent MLP analyses represents a promising tool for the development of a non-invasive prediction system and may assist in developing management and surveillance procedures.

Overview of the National Occupational Mortality Surveillance (NOMS) system: leukemia and acute myocardial infarction risk by industry and occupation in 30 US states 1985-1999, 2003-2004, and 2007

BACKGROUND

Cancer and chronic disease are leading causes of death in the US with an estimated cost of $46 billion.

METHODS

We analyzed 11 million cause-specific deaths of US workers age 18-64 years in 30 states during 1985-1999, 2003-2004, and 2007 by occupation, industry, race, gender, and Hispanic origin.

RESULTS

The highest significantly elevated proportionate leukemia mortality was observed in engineers, protective service, and advertising sales manager occupations and in banks/savings &loans/credit agencies, public safety, and public administration industries. The highest significantly elevated smoking-adjusted acute myocardial infarction mortality was noted in industrial and refractory machinery mechanics, farmers, mining machine operators, and agricultural worker occupations; and wholesale farm supplies, agricultural chemical, synthetic rubber, and agricultural crop industries.

CONCLUSIONS

Significantly elevated risks for acute myocardial infarction and leukemia were observed across several occupations and industries that confirm existing reports and add new information. Interested investigators can access the NOMS website at http://www.cdc.gov/niosh/topics/NOMS/.

Occupational exposure to crystalline silica and the risk of lung cancer in Canadian men

Crystalline silica is a recognized carcinogen, but the association with lung cancer at lower levels of exposure has not been well characterized. This study investigated the relationship between occupational silica exposure and lung cancer and the combined effects of cigarette smoking and silica exposure on lung cancer risk. A population-based case-control study was conducted in eight Canadian provinces between 1994 and 1997. Self-reported questionnaires were used to obtain a lifetime occupational history and information on other risk factors. Occupational hygienists assigned silica exposures to each job based on concentration, frequency and reliability. Data from 1681 incident lung cancer cases and 2053 controls were analyzed using logistic regression to estimate odds ratios (OR) and their 95% confidence intervals (CI). Models included adjustments for cigarette smoking, lifetime residential second-hand smoke and occupational exposure to diesel and gasoline engine emissions. Relative to the unexposed, increasing duration of silica exposure at any concentration was associated with a significant trend in lung cancer risk (OR ≥ 30 years: 1.67, 1.21-2.24; ptrend  = 0.002). The highest tertile of cumulative silica exposure was associated with lung cancer (OR = 1.81, 1.34-2.42; ptrend  = 0.004) relative to the lowest. Men exposed to silica for ≥30 years with ≥40 cigarette pack-years had the highest risk relative to those unexposed with <10 pack-years (OR = 42.53, 23.54-76.83). The joint relationship with smoking was consistent with a multiplicative model. Our findings suggest that occupational exposure to silica is a risk factor for lung cancer, independently from active and passive smoking, as well as from exposure to other lung carcinogens.

The burden of mortality with costs in productivity loss from occupational cancer in Italy

BACKGROUND

The costs of productivity loss due to occupational cancer mortality are rarely investigated. An estimate of occupational cancer deaths in Italy in 2006 and an approximation of the resultant costs from medical and non-medical expenditures together with figures of remuneration lost are provided.

METHODS

Occupational cancer deaths, obtained from the application of the attributable fraction (AF) to mortality data (source: Italian National Institute of Statistics), were used to calculate the Potential Years of Life Lost (PYLLs), the Potential Years of Working Life Lost (PYWLLs) and the costs of the loss of productive life. The health care costs for any cancer was applied to the estimated number of occupational cancer cases to obtain the total cost.

RESULTS

Around 8,000-8,500 deaths/year from occupational cancer are estimated to occur in Italy, corresponding to 170,000 PYLLs and more than 16,000 PYWLLs, leading to around 360,000,000 euros in indirect economic loss. Health care costs of occupational cancer are estimated at 456,000,000 euros.

CONCLUSIONS

Occupational cancer is of major concern in terms of mortality and economic productivity loss. Preventive efforts in evaluating ongoing risks and current exposures are strongly recommended to health policy-makers.

Identification of occupational cancer risks in British Columbia, Canada: a population-based case-control study of 1,155 cases of colon cancer

Objective

Cancer has been recognized to have environmental origin, but occupational cancer risk studies have not been fully documented. The objective of this paper was to identify occupations and industries with elevated colon cancer risk based on lifetime occupational histories collected from 15,463 incident cancer cases.

Method

A group matched case-control design was used. All cases were diagnosed with histologically proven colon cancers, with cancer controls being all other cancer sites, excluding rectum, lung and unknown primary, diagnosed at the same period of time from the British Columbia Cancer Registry. Data analyses were done on all 597 Canadian standard occupation titles and 1,104 standard industry titles using conditional logistic regression for matched data sets and the likelihood ratio test.

Results

Excess colon cancer risks was observed in a number of occupations and industries, particularly those with low physical activity and those involving exposure to asbestos, wood dusts, engine exhaust and diesel engine emissions, and ammonia.

Discussion

The results of our study are in line with those from the literature and further suggest that exposure to wood dusts and to ammonia may carry an increased occupational risk of colon cancer.

Exposure to multiple pesticides and risk of non-Hodgkin lymphoma in men from six Canadian provinces

Non-Hodgkin lymphoma (NHL) has been linked to several agricultural exposures, including some commonly used pesticides. Although there is a significant body of literature examining the effects of exposure to individual pesticides on NHL, the impact of exposure to multiple pesticides or specific pesticide combinations has not been explored in depth. Data from a six-province Canadian case-control study conducted between 1991 and 1994 were analyzed to investigate the relationship between NHL, the total number of pesticides used and some common pesticide combinations. Cases (n=513) were identified through hospital records and provincial cancer registries and controls (n=1,506), frequency matched to cases by age and province of residence, were obtained through provincial health records, telephone listings, or voter lists. In multiple logistic regression analyses, risk of NHL increased with the number of pesticides used. Similar results were obtained in analyses restricted to herbicides, insecticides and several pesticide classes. Odds ratios increased further when only 'potentially carcinogenic' pesticides were considered (OR[one pesticide]=1.30, 95% CI=0.90-1.88; OR[two to four]=1.54, CI=1.11-2.12; OR[five or more]=1.94, CI=1.17-3.23). Elevated risks were also found among those reporting use of malathion in combination with several other pesticides. These analyses support and extend previous findings that the risk of NHL increases with the number of pesticides used and some pesticide combinations.

Clarifying carcinogenicity of ethylbenzene

Ethylbenzene has been evaluated for carcinogenic activity in Fischer rats and B6C3F1 mice exposed by inhalation (Chan et al., 1998; Chan, 1999) and in Sprague-Dawley rats after oral exposure (Maltoni et al., 1985,1997). Bioassay findings are summarized below to expand on those not stated clearly or completely in Saghir et al. (2010). Overall in these three studies animals exposed to ethylbenzene had increased tumors in rats for kidneys, testes, head (including rare neuroesthesioepitheliomas), and total malignant tumors, whilst in mice tumor incidences were increased in the lung and liver (Huff, 2002). Thus ethylbenzene was carcinogenic by two exposure routes to both sexes of two species of rodents, two strains of rats, and one strain of mice, causing collectively tumors in five different target organs and a composite of "total malignant" tumors.

Generational risks for cancers not related to tobacco, screening, or treatment in the United States

BACKGROUND

To assess trends in cancer, the authors evaluated the risk of 1 generation compared with that 25 years earlier (generational risk) for 3 groupings of cancers: those related to tobacco; those that reflect advances in screening or treatment; and a residual category of all other cancers.

METHODS

In individuals ages 20 years to 84 years, age-period-cohort models were used to summarize time trends in terms of generational risk and average annual percentage change for US cancer incidence (1975-2004) and mortality (1970-2004) rates associated with these 3 cancer groupings.

RESULTS

Adult white men today developed 16% fewer tobacco-related cancers and had 21% fewer deaths because of those cancers than their fathers' generation, whereas adult white women experienced increases of 28% and 19%, respectively, relative to their mothers. The incidence of commonly screened cancers rose 74% in men and 10% in women, whereas mortality fell 25% in men and 31% in women. For cancers that have not been linked chiefly to tobacco or screening, the incidence was 34% and 23% higher in white men and white women, respectively, than in their parents' generation 25 years earlier. Mortality in this residual category decreased 14% in men and 18% in women. Results among blacks were qualitatively similar to those among whites.

CONCLUSIONS

Despite declining overall cancer death rates, adults are experiencing increased incidence of cancers that are not associated with tobacco or screening relative to their parents. Future research should examine whether similar patterns are exhibited in other modern nations and should identify population-wide avoidable risks that could account for unexplained increases in these residual cancers.

Squamous cell carcinoma of the scrotum in a Nigerian: case report

Squamous cell carcinoma of the scrotum is rare and to the best of our knowledge has never been reported from Nigeria. We report on a case thought to be occupation-related in a 42-year old Nigerian taxi driver who had previously been an automobile mechanic and later a long-haul truck driver. He presented with a stage D disease and only palliation was feasible.

Recent mortality from pleural mesothelioma, historical patterns of asbestos use, and adoption of bans: a global assessment

BACKGROUND

In response to the health risks posed by asbestos exposure, some countries have imposed strict regulations and adopted bans, whereas other countries have intervened less and continue to use varying quantities of asbestos.

OBJECTIVES

This study was designed to assess, on a global scale, national experiences of recent mortality from pleural mesothelioma, historical trends in asbestos use, adoption of bans, and their possible interrelationships.

METHODS

For 31 countries with available data, we analyzed recent pleural mesothelioma (International Classification of Diseases, 10th Revision) mortality rates (MRs) using age-adjusted period MRs (deaths/million/year) from 1996 to 2005. We calculated annual percent changes (APCs) in age-adjusted MRs to characterize trends during the period. We characterized historical patterns of asbestos use by per capita asbestos use (kilograms per capita/year) and the status of national bans.

RESULTS

Period MRs increased with statistical significance in five countries, with marginal significance in two countries, and were equivocal in 24 countries (five countries in Northern and Western Europe recorded negative APC values). Countries adopting asbestos bans reduced use rates about twice as fast as those not adopting bans. Turning points in use preceded bans. Change in asbestos use during 1970-1985 was a significant predictor of APC in mortality for pleural mesothelioma, with an adjusted R(2) value of 0.47 (p < 0.0001).

CONCLUSIONS

The observed disparities in global mesothelioma trends likely relate to country-to-country disparities in asbestos use trends.