Documents van Tongeren, Martie 18 results

"From 1 July 2024, Australia has banned the use, supply and manufacture of engineered stone, also known as artificial stone, which is made from crystalline silica-containing aggregates bonded with a polymer resin. Engineered stone is defined as an artificial product containing at least 1% crystalline silica on a weight basis. This far-reaching policy is the first of its kind in the world and is similar to the bans on the use of asbestos and asbestos products that are in place in many countries worldwide (currently 70 countries). ..."

"Objective
This study aimed to construct a job exposure matrix (JEM) for risk of becoming infected with the SARS-CoV-2 virus in an occupational setting.
Methods
Experts in occupational epidemiology from three European countries (Denmark, The Netherlands and the United Kingdom) defined the relevant exposure and workplace characteristics with regard to possible exposure to the SARS-CoV-2 virus. In an iterative process, experts rated the different dimensions of the COVID-19-JEM for each job title within the International Standard Classification of Occupations system 2008 (ISCO-08). Agreement scores, weighted kappas, and variances were estimated.
Results
The COVID-19-JEM contains four determinants of transmission risk [number of people, nature of contacts, contaminated workspaces and location (indoors or outdoors)], two mitigation measures (social distancing and face covering), and two factors for precarious work (income insecurity and proportion of migrants). Agreement scores ranged from 0.27 [95% confidence interval (CI) 0.25–0.29] for ‘migrants' to 0.76 (95% CI 0.74–0.78) for ‘nature of contacts'. Weighted kappas indicated moderate-to-good agreement for all dimensions [ranging from 0.60 (95% CI 0.60–0.60) for ‘face covering' to 0.80 (95% CI 0.80–0.80) for ‘contaminated workspaces'], except for ‘migrants' (0.14 (95% CI -0.07–0.36). As country differences remained after several consensus exercises, the COVID-19-JEM also has a country-axis.
Conclusions
The COVID-19-JEM assesses the risk at population level using eight dimensions related to SARS-COV-2 infections at work and will improve our ability to investigate work-related risk factors in epidemiological studies. The dimensions of the COVID-19-JEM could also be valuable for other future communicable diseases in the workplace."

"As workplace air measurements of manufactured nanoparticles are relatively expensive to conduct, models can be helpful for a first tier assessment of exposure. A conceptual model was developed to give a framework for such models. The basis for the model is an analysis of the fate and underlying mechanisms of nanoparticles emitted by a source during transport to a receptor. Four source domains are distinguished; that is, production, handling of bulk product, dispersion of ready-to-use nanoproducts, fracturing and abrasion of end products. These domains represent different generation mechanisms that determine particle emission characteristics; for example, emission rate, particle size distribution, and source location. During transport, homogeneous coagulation, scavenging, and surface deposition will determine the fate of the particles and cause changes in both particle size distributions and number concentrations. The degree of impact of these processes will be determined by a variety of factors including the concentration and size mode of the emitted nanoparticles and background aerosols, source to receptor distance, and ventilation characteristics. The second part of the paper focuses on to what extent the conceptual model could be fit into an existing mechanistic predictive model for ''conventional'' exposures. The model should be seen as a framework for characterization of exposure to (manufactured) nanoparticles and future exposure modeling."

"OBJECTIVE: To investigate whether the risks of mortality from brain cancer are related to occupational exposure to magnetic fields. METHODS: A total of 112 cases of primary brain cancer (1972-91) were identified from a cohort of 84,018 male and female employees of the (then) Central Electricity Generating Board and its privatised successor companies. Individual cumulative occupational exposures to magnetic fields were estimated by linking available computerised job history data with magnetic field measurements collected over 675 person- workshifts. Estimated exposure histories of the case workers were compared with those of 654 control workers drawn from the cohort (nested case-control study), by means of conditional logistic regression. RESULTS: For exposure assessments based on arithmetic means, the risk of mortality from brain cancer for subjects with an estimated cumulative exposure to magnetic fields of 5.4-13.4 microT.y v subjects with lower exposures (0.0-5.3 microT.y) was 1.04 (95% confidence interval (95% CI) 0.60 to 1.80). The corresponding relative risk in subjects with higher exposures (> or = 13.5 microT.y) was 0.95 (95% CI 0.54 to 1.69). There was no indication of a positive trend for cumulative exposure and risk of mortality from brain cancer either when the analysis used exposure assessments based on geometric means or when the analysis was restricted to exposures received within five years of the case diagnosis (or corresponding period for controls). CONCLUSIONS: Although the exposure categorisation was based solely on recent observations, the study findings do not support the hypothesis that the risk of brain cancer is associated with occupational exposure to magnetic fields. "

"The aim of this project was to produce an updated estimate of the current burden of occupational cancer specifically for Great Britain. The primary measure of the burden of cancer used in this project was the attributable fraction (AF) i.e. the proportion of cases that would not have occurred in the absence of exposure; this was then used to estimate the attributable numbers. This involved obtaining data on the risk of the disease due to the exposure of interest, taking into account confounding factors and overlapping exposures, and the proportion of the target population exposed over the period in which relevant exposure occurred. Estimation was carried out for occupational exposures classified by the International Agency for Research on Cancer (IARC) as group 1 (established) and 2A carcinogens (probable).
This project is the first to quantify in detail the burden of cancer due to occupation specifically for GB. There are several sources of uncertainty in the estimates, including exclusion of other potential carcinogenic agents, inaccurate or approximate data and methodological issues. On balance, the estimates are likely to be a conservative estimate of the total attributable burden. Forthcoming reports will present the results for; estimates of Disability-Adjusted Life Years; methods to predict future estimates of the occupational cancers with examples based on important hazards; and the results of sensitivity analysis of these estimates to sources of uncertainty and bias."

"Background: Establishing the routes of exposure is a fundamental component of the risk assessment process for every dangerous substance. The present study systematically reviews the available literature to assess the relevance of the different routes and forms of exposure that are of concern for the protection of workers during the manufacture, handling, or end-use of engineered nanomaterials (ENMs).
Methods: A systematic review of the peer-reviewed literature published between 2000 and 2015 was completed. Only studies including measurements of inhalation or dermal exposure were selected and used to identify the exposure situations for which the measurements were collected. The identified exposure situations were grouped based on the type of ENM (i.e. carbon nanotubes and fibres, silicon-based, titanium dioxide, other metal oxides, pure elemental metals, and other ENMs) and activity involved. The grouped exposure situations were assessed to provide a conclusion regarding the likelihood, form, and route of exposure. Assessment of the likelihood of exposure was based on well-defined criteria using a previously established decision logic for inhalation exposure and the outputs from measurements and/or conceptual models for dermal/ingestion exposure. For each combination of nano-activity and type of ENM, the aggregated likelihood across all relevant individual assessments was used to draw conclusions about the relevance of both the inhalation and dermal/ingestion routes. Based on the quality of the data, the strength of the evidence was also evaluated.
Results: One hundred and seven studies were identified during the review process, reporting 424 individual exposure assessments. Measurement data were limited for dermal/ingestion exposure and for inhalation exposure for downstream use and end-of-life. However, the data provided high-quality evidence that in occupational settings all three routes can be of relevance for exposure to ENMs. In general, whenever inhalation exposure occurs then dermal and inadvertent ingestion exposure may occur due to surface deposition and transfer due to the ENMs release. However, for some forms of exposure (e.g. suspension/liquids), dermal exposure can occur even when inhalation exposure is unlikely. An increased likelihood of exposure was observed for manual activities such as cleaning and maintenance, collection/harvesting, spraying, and finishing as well as those involving feeding into a process and handling of powders outside enclosures. The likelihood of exposure was affected by the presence of risk management measures and the scale of the production involved.
Conclusion: This literature review provides evidence that for ENMs, as found for other materials, the likelihood of the exposure depends largely on the physical form of the substance as well as the applied process and operational conditions. These results can be used to provide first indications of the likelihood of exposure and guidance for exposure controls in workplaces. However, there is a clear lack of high-quality exposure data, in particular for downstream use and end-of-life scenarios and in low- and medium-income countries."

"When applying simple screening (Tier 1) tools to estimate exposure to chemicals in a given exposure situation under the Registration, Evaluation, Authorisation and restriction of CHemicals Regulation 2006 (REACH), users must select from several possible input parameters. Previous studies have suggested that results from exposure assessments using expert judgement and from the use of modelling tools can vary considerably between assessors. This study aimed to investigate the between-user reliability of Tier 1 tools. A remote-completion exercise and in person workshop were used to identify and evaluate tool parameters and factors such as user demographics that may be potentially associated with between-user variability. Participants (N = 146) generated dermal and inhalation exposure estimates (N = 4066) from specified workplace descriptions (‘exposure situations') and Tier 1 tool combinations (N = 20). Interactions between users, tools, and situations were investigated and described. Systematic variation associated with individual users was minor compared with random between-user variation. Although variation was observed between choices made for the majority of input parameters, differing choices of Process Category (‘PROC') code/activity descriptor and dustiness level impacted most on the resultant exposure estimates. Exposure estimates ranging over several orders of magnitude were generated for the same exposure situation by different tool users. Such unpredictable between-user variation will reduce consistency within REACH processes and could result in under-estimation or overestimation of exposure, risking worker ill-health or the implementation of unnecessary risk controls, respectively. Implementation of additional support and quality control systems for all tool users is needed to reduce between-assessor variation and so ensure both the protection of worker health and avoidance of unnecessary business risk management expenditure."