Economic evaluation of interventions to reduce solar ultraviolet radiation (UVR) exposure among construction workers.

Solar ultraviolet radiation is one of the most common occupational carcinogens in Canada and is responsible for approximately 5,556 non-melanoma skin cancers per year. A large part of these cases are preventable by reducing solar ultraviolet radiation exposure. In this study, investigators estimated the potential economic impacts of different solar ultraviolet radiation reduction interventions among construction workers, as they are one of the largest at-risk occupational groups. Investigators performed an economic evaluation from a societal perspective, by comparing incremental costs in relation to incremental benefits achieved by two interventions-use of personal protective equipment by all exposed individuals and use of shade structure wherever and whenever feasible. Interventions costs were estimated for 2020-2050, and benefits with a 10-year delay, i.e., for the period 2030-2060. Economic evaluation estimates were reported by intervention costs, total costs of non-melanoma skin cancers cases averted, incremental cost per avert case, return on investment, and the break-even point. Various sensitivity analyses were undertaken with key parameters. Our findings indicate that if the rising trend of incidence continues, cases will be double in 2060, whereas by using personal protective equipment or shade structure, with the best-case scenario of full ultraviolet radiation removal, would result in 6,034 and 2,945 cases averted over 30 years, respectively. This translates into a total of $38.0 and $20.5 million of averted costs (all monetary values represented in 2017 Canadian dollars). Under this scenario investigators expect that by 2060, for every dollar invested in personal protective equipment and shade structures, $0.49 and $0.35 will be returned, respectively. Findings also suggested that under a conservative scenario, prevention of non-melanoma skin cancer cases by personal protective equipment and shade structures resulted in $5,812 and $7,355 incremental costs, respectively, over the 30-year period. This study provides important insights for decision makers about the potential impacts of solar ultraviolet radiation reduction interventions in the construction sector and other sectors with substantial outdoor work. Our estimates also can raise awareness of the importance of solar ultraviolet radiation reduction interventions.

The current burden of cancer attributable to occupational exposures in Canada.

Exposure to occupational carcinogens is often overlooked as a contributor to the burden of cancer. To estimate the proportion of cancer cases attributable to occupational exposure in Canada in 2011, exposure prevalence and levels of 44 carcinogens were informed by data from the Canadian carcinogen exposure surveillance project (CAREX Canada). These were used with Canadian Census (between 1961 and 2011) and Labour Force Survey (annual surveys between 1976 and 2013) data to estimate the number of workers ever exposed to occupational carcinogens. Risk estimates of the association between each carcinogen and cancer site were selected mainly from published literature reviews. Population attributable risks were estimated using Levin's equation and applied to the 2011 cancer statistics from the Canadian Cancer Registry. It is estimated that 15.5 million Canadians alive in 2011 were exposed, during at least one year between 1961 and 2001, to at least one carcinogen in the workplace. Overall, we estimated that in 2011, between 3.9% (95% CI: 3.1%-8.1%) and 4.2% (95% CI: 3.3%-8.7%) of all incident cases of cancer were due to occupational exposure, corresponding to lower and upper numbers of 7700-21,800 cases. Five of the cancer sites - mesothelioma, non-melanoma skin cancer, lung, female breast, and urinary bladder - account for a total of 7600 to 21,200 cancers attributable to occupational exposures such as solar radiation, asbestos, diesel engine exhaust, crystalline silica, and night shift work. Our study highlights cancer sites and occupational exposures that need recognition and efforts by all stakeholders to avoid preventable cancers in the future.

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.

Burden of lung cancer attributable to occupational diesel engine exhaust exposure in Canada.

OBJECTIVE: To estimate the population attributable fraction (PAF) and number of incident and fatal lung cancers in Canada from occupational exposure to diesel engine exhaust (DEE). METHODS: DEE exposure prevalence and level estimates were used with Canadian Census and Labour Force Survey data to model the exposed population across the risk exposure period (REP, 1961-2001). Relative risks of lung cancer were calculated based on a meta-regression selected from the literature. PAFs were calculated using Levin's equation and applied to the 2011 lung cancer statistics obtained from the Canadian Cancer Registry. RESULTS: We estimated that 2.4% (95% CI 1.6% to 6.6%) of lung cancers in Canada are attributable to occupational DEE exposure, corresponding to approximately 560 (95% CI 380 to 1570) incident and 460 (95% CI 310 to 1270) fatal lung cancers in 2011. Overall, 1.6 million individuals alive in 2011 were occupationally exposed to DEE during the REP, 97% of whom were male. Occupations with the highest burden were underground miners, truck drivers and mechanics. Half of the attributable lung cancers occurred among workers with low exposure. CONCLUSIONS: This is the first study to quantify the burden of lung cancer attributable to occupational DEE exposure in Canada. Our results underscore a large potential for prevention, and a large public health impact from occupational exposure to low levels of DEE.

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.

The economic burden of lung cancer and mesothelioma due to occupational and para-occupational asbestos exposure.

OBJECTIVES: To estimate the economic burden of lung cancer and mesothelioma due to occupational and para-occupational asbestos exposure in Canada. METHODS: We estimate the lifetime cost of newly diagnosed lung cancer and mesothelioma cases associated with occupational and para-occupational asbestos exposure for calendar year 2011 based on the societal perspective. The key cost components considered are healthcare costs, productivity and output costs, and quality of life costs. RESULTS: There were 427 cases of newly diagnosed mesothelioma cases and 1904 lung cancer cases attributable to asbestos exposure in 2011 for a total of 2331 cases. Our estimate of the economic burden is $C831 million in direct and indirect costs for newly identified cases of mesothelioma and lung cancer and $C1.5 billion in quality of life costs based on a value of $C100 000 per quality-adjusted life year. This amounts to $C356 429 and $C652 369 per case, respectively. CONCLUSIONS: The economic burden of lung cancer and mesothelioma associated with occupational and para-occupational asbestos exposure is substantial. The estimate identified is for 2331 newly diagnosed, occupational and para-occupational exposure cases in 2011, so it is only a portion of the burden of existing cases in that year. Our findings provide important information for policy decision makers for priority setting, in particular the merits of banning the mining of asbestos and use of products containing asbestos in countries where they are still allowed and also the merits of asbestos removal in older buildings with asbestos insulation.

Occupational patterns of opioid-related harms comparing a cohort of formerly injured workers to the general population in Ontario, Canada.

OBJECTIVES: The role of work-related injuries as a risk factor for opioid-related harms has been hypothesized, but little data exist to support this relationship. The objective was to compare the incidence of opioid-related harms among a cohort of formerly injured workers to the general population in Ontario, Canada. METHODS: Workers' compensation claimants (1983-2019) were linked to emergency department (ED) and hospitalization records (2006-2020). Incident rates of opioid-related poisonings and mental and behavioural disorders were estimated among 1.7 million workers and in the general population. Standardized incidence ratios (SIRs) and 95% confidence intervals (CI) were calculated, adjusting for age, sex, year, and region. RESULTS: Compared to the general population, opioid-related poisonings among this group of formerly injured workers were elevated in both ED (SIR = 2.41, 95% CI = 2.37-2.45) and hospitalization records (SIR = 1.54, 95% CI = 1.50-1.59). Opioid-related mental and behavioural disorders were also elevated compared to the general population (ED visits: SIR = 1.86, 95% CI = 1.83-1.89; hospitalizations: SIR = 1.42, 95% CI = 1.38-1.47). Most occupations and industries had higher risks of harm compared to the general population, particularly construction, materials handling, processing (mineral, metal, chemical), and machining and related occupations. Teaching occupations displayed decreased risks of harm. CONCLUSION: Findings support the hypothesis that work-related injuries have a role as a preventable risk factor for opioid-related harms. Strategies aimed at primary prevention of occupational injuries and secondary prevention of work disability and long-term opioid use are warranted.

RéSUMé: OBJECTIFS: Le rôle des accidents du travail en tant que facteur de risque pour les méfaits liés aux opioïdes a été supposé, mais il existe peu de données pour étayer cette relation. L'objectif était de comparer l'incidence des méfaits liés aux opioïdes dans une cohorte de travailleurs anciennement blessés à la population générale de l'Ontario, au Canada. MéTHODES: Les dossiers de demandes d'indemnisation des travailleurs (1983‒2019) ont été reliés aux dossiers des services d'urgence et d'hospitalisation (2006‒2020). Les taux d'incidence des empoisonnements liés aux opioïdes et des troubles mentaux et comportementaux ont été estimés parmi 1,7 million de travailleurs et dans la population générale. Les ratios d'incidence standardisés (RIS) et les intervalles de confiance (IC) à 95 % ont été calculés en tenant compte de l'âge, du sexe, de l'année et de la région. RéSULTATS: Comparativement à la population générale, les empoisonnements liés aux opioïdes chez ce groupe de travailleurs anciennement blessés étaient élevés dans les dossiers des services d'urgence (RIS = 2,41, IC à 95 % = 2,37-2,45) et d'hospitalisation (RIS = 1,54, IC à 95 % = 1,50-1,59). Les troubles mentaux et comportementaux liés aux opioïdes étaient également élevés par rapport à la population générale (visites aux urgences RIS = 1,86, IC à 95 % = 1,83-1,89; hospitalisations RIS = 1,42, IC à 95 % = 1,38-1,47). La plupart des professions et des secteurs d'activité présentaient des risques de méfaits plus élevés par rapport à la population générale, en particulier la construction, la manutention, le traitement (minéral, métallique, chimique) et l'usinage des matières premières et activités connexes. Les professions de l'enseignement présentaient des risques de méfaits moindres. CONCLUSION: Les résultats confirment l'hypothèse selon laquelle les accidents du travail constituent un facteur de risque évitable pour les méfaits liés aux opioïdes. Des stratégies visant la prévention primaire des accidents du travail et la prévention secondaire de l'incapacité de travail et de la consommation d'opioïdes à long terme sont justifiées.

Ursolic acid regulates gut microbiota and corrects the imbalance of Th17/Treg cells in T1DM rats.

Ursolic acid (UA), a natural pentacyclic triterpenoid obtained from fruit and several traditional Chinese medicinal plants, exhibits anti-inflammatory and hypoglycemic properties. However, its protective effects against type 1 diabetes mellitus (T1DM) have not been explored. In this study, streptozotocin-induced T1DM rat models were established and treated with UA for six weeks. T1DM rats treated with UA were used to observe the effects of UA on body weight and fasting blood glucose (FBG) levels. Pathological changes in the pancreas were observed using immunohistochemical staining. The gut microbiota distribution was measured using 16S rDNA high-throughput sequencing. The proportions of Th17 and Treg cells were examined using flow cytometry. Protein and mRNA expression of molecules involved in Th17/Treg cell differentiation were assessed by quantitative real-time PCR and western blotting. The correlation between gut microbiota and Th17/Treg cell differentiation in T1DM was analyzed using redundancy analysis (RDA) analysis. Compared with the model group, FBG levels declined, and the progressive destruction of pancreatic ß cells was alleviated. The diversity and uniformity of gut microbiota in T1DM rats treated with UA increased significantly. Interestingly, the Th17/Treg cell differentiation imbalance was corrected and positively correlated with the expression of Foxp3 and IL-10, and negatively correlated with the expression of RORγt, IL-17A, and TNF-α. These findings suggest that UA can lower FBG levels in T1DM rats, delay the progressive destruction of pancreatic ß-cells, and modulate gut microbiota homeostasis and immune function in streptozotocin-induced T1DM rats.

An ultra-stable reference electrode for scaled all-vanadium redox flow batteries.

Redox flow batteries (RFBs) have been investigated as a promising energy storage system (ESS) for grid applications over the past several decades due to their unique features, which include the separation of energy and power output, high safety, and long cycle life. It is therefore vital but still in severe deficiency to understand the reliability of RFBs, and the mechanisms that cause degradation with time. One of the primary challenges involves the unseparated contributions from individual electrodes due to the absence of a stable reference electrode (RE), particularly for long-term cycle testing in a scaled cell. Herein, we first develop an ultra-stable RE for scaled all-vanadium RFBs. The newly developed RE, based on a dynamic hydrogen electrode (DHE) with a novel design on the area (size) and surface roughness of platinum electrodes, demonstrates high accuracy and long-term stability that enables in situ monitoring of individual electrode potentials throughout 500 cycles. By introducing the RE approach to decouple the cathode and anode in conjunction with the measurement of voltage profiles, overpotentials and polarization curves, the reliability and degradation mechanism of a scaled all-vanadium RFB are further explored, revealing the diverse behaviors of individual electrodes. This exploratory work will benefit the future design and development of a stable RE for a scaled ESS, as well as the fundamental understanding of the RFB's reliability and degradation mechanism.

Occupational Exposure to Wood Dust and the Burden of Nasopharynx and Sinonasal Cancer in Canada.

BACKGROUND: Millions of workers around the world are exposed to wood dust, as a by-product of woodworking. Nasopharynx cancers (NPCs) and sinonasal cancers (SNCs) are two cancers that can be caused by occupational exposure to wood dust, but there is little evidence regarding their burden in Canada. OBJECTIVE: the aim of this study was to estimate the incidence and economic burden of newly diagnosed cases of NPC and SNC in 2011 in Canada, attributable to occupational exposures to wood dust. METHODS: calculating the incidence of cancer attributable to occupational exposure involved three steps of defining relative risk, assessing the prevalence of exposure and population modelling. We estimated the lifetime costs of newly diagnosed NPC and SNC from the societal perspective. The three major cost categories that we considered were direct costs (healthcare costs, out-of-pocket costs, and informal caregiving costs), indirect costs (labour productivity/output costs, employer adjustment costs, and home production losses), and intangible costs (health-related quality of life losses). To generate an estimate of economic burden, we used secondary data from multiple sources and applied them to our computational model developed from an extensive literature review. RESULTS: From approximately 1.3 million workers exposed to wood dust, we expected 28%, 43% and 29% were exposed to low, medium, and high levels, respectively. We estimated from 235 newly diagnosed cases of NPC and 245 newly diagnosed cases of SNC, 4.6% (11 cases) and 4.4% (11 cases) were attributed to occupational exposure to wood dust, respectively. Our estimates of the economic burden of occupational NPC and SNC were about CAD 5.4 million (CAD 496,311 per-case) and CAD 6.7 million (CAD 627,437 per-case), respectively. For NPC direct costs constituted approximately 20% of all costs, and indirect and intangible costs accounted for 55% and 25%, while for SNC the breakdown distribution were 16%, 42% and 42%, respectively. CONCLUSIONS: Our estimates highlighted the importance of occupational NPC and SNC amongst other occupational cancers, especially in countries with large wood-related industries. This paper also serves the information needs of policymakers who are seeking to make evidence-based decisions about occupational cancer prevention efforts.

Ex-Situ Evaluation of Commercial Polymer Membranes for Vanadium Redox Flow Batteries (VRFBs).

Polymer membranes play a vital role in vanadium redox flow batteries (VRFBs), acting as a separator between the two compartments, an electronic insulator for maintaining electrical neutrality of the cell, and an ionic conductor for allowing the transport of ionic charge carriers. It is a major influencer of VRFB performance, but also identified as one of the major factors limiting the large-scale implementation of VRFB technology in energy storage applications due to its cost and durability. In this work, five (5) high-priority characteristics of membranes related to VRFB performance were selected as major considerable factors for membrane screening before in-situ testing. Eight (8) state-of-the-art of commercially available ion exchange membranes (IEMs) were specifically selected, evaluated and compared by a set of ex-situ assessment approaches to determine the possibility of the membranes applied for VRFB. The results recommend perfluorosulfonic acid (PFSA) membranes and hydrocarbon anion exchange membranes (AEMs) as the candidates for further in-situ testing, while one hydrocarbon cation exchange membrane (CEM) is not recommended for VRFB application due to its relatively high VO2+ ion crossover and low mechanical stability during/after the chemical stability test. This work could provide VRFB researchers and industry a valuable reference for selecting the polymer membrane materials before VRFB in-situ testing.

Break-even Analysis of Respirable Crystalline Silica (RCS) Exposure Interventions in the Construction Sector.

OBJECTIVE: We investigated long-term economic impacts of respirable crystalline silica (RCS) removal interventions in the construction at the societal level. METHODS: We estimated costs and benefits of two RCS exposure interventions, use of "respirators" and "wet method," over a 30-year time period. We identified economic impacts of the interventions under four different scenarios. RESULTS: Under current practices, we estimated that approximately 125 lung cancer cases attributable to RCS exposure would arise in 2060. Under the full exposure removal scenario, we estimated there would be 53 new cases. Over the 30-year time period, the estimated cumulative averted cases are 787 and 482 for respirators and wet method, respectively, which amount to net benefits of $422.13 and $394.92 million. CONCLUSIONS: Findings provide important information for policymakers seeking to reduce the economic burden of occupational lung cancer in society.

The Economic Burden of Bladder Cancer Due to Occupational Exposure.

OBJECTIVE: To estimate the economic burden of bladder cancer due to occupational exposures. METHODS: Using a societal perspective, we estimate the lifetime costs of newly diagnosed cases of bladder cancer in Canada that is associated with occupational exposure for the calendar year 2011. The three major categories we consider are direct, indirect, and quality of life costs. RESULTS: There were 199 newly identified cases of bladder cancer. The estimated total cost of bladder cancer for new cases in 2011 was $131 million and an average per-case cost of $658,055 CAD (2011 dollars). Of the total costs, direct costs accounted for 6%, indirect costs 29%, and health-related quality of life costs 65%. CONCLUSIONS: The per-case economic burden of bladder cancer due to occupational exposure is substantial which suggests the importance and value of exposure reduction.