RSS 1.0Miscellaneous
Recent Submissions
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A Method to Assess the Relevance of Nanomaterial Dissolution During Reactivity Testing.The reactivity of particle surfaces can be used as a criterion to group nanoforms (NFs) based on similar potential hazard. Since NFs may partially or completely dissolve over the duration of the assays, with the ions themselves inducing a response, reactivity assays commonly measure the additive reactivity of the particles and ions combined. Here, we determine the concentration of ions released over the course of particle testing, and determine the relative contributions of the released ions to the total reactivity measured. We differentiate three classes of reactivity, defined as being A) dominated by particles, B) additive of particles and ions, or C) dominated by ions. We provide examples for each class by analyzing the NF reactivity of Fe2O3, ZnO, CuO, Ag using the ferric reduction ability of serum (FRAS) assay. Furthermore, another two reactivity tests were performed: Dichlorodihydrofluorescin diacetate (DCFH2‑DA) assay and electron paramagnetic resonance (EPR) spectroscopy. We compare assays and demonstrate that the dose‑response may be almost entirely assigned to ions in one assay (CuO in DCFH2‑DA), but to particles in others (CuO in EPR and FRAS). When considering this data, we conclude that one cannot specify the contribution of ions to NF toxicity for a certain NF, but only for a certain NF in a specific assay, medium and dose. The extent of dissolution depends on the buffer used, particle concentration applied, and duration of exposure. This culminates in the DCFH2‑DA, EPR, FRAS assays being performed under different ion‑to‑particle ratios, and differing in their sensitivity towards reactions induced by either ions or particles. If applied for grouping, read‑across, or other concepts based on the similarity of partially soluble NFs, results on reactivity should only be compared if measured by the same assay, incubation time, and dose range.
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Dynamic prediction model to identify young children at high risk of future overweight: Development and internal validation in a cohort study.After backward selection in a Generalized Estimating Equations analysis, the prediction model included the baseline predictors maternal BMI, paternal BMI, paternal education, birthweight, sex, ethnicity and indoor smoke exposure; and the longitudinal predictors BMI SDS, and the linear and quadratic terms of the growth curve describing a child's BMI SDS development over time, as well as the longitudinal predictors' interactions with age. The area under the curve of the model after internal validation was 0.845 and Nagelkerke R2 was 0.351.
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Effects of short-term exposures to ultrafine particles near an airport in healthy subjects.The PNC was on average 53,500 particles/cm3 (range 10,500-173,200). A 5-95th percentile increase in exposure to UFP (i.e. 125,400 particles/cm3) was associated with a decrease in FVC of -73.8 mL (95% CI -138.8 - -0.4) and a prolongation of the corrected QT (QTc) interval by 9.9 ms (95% CI 2.0 - 19.1). These effects were associated with particles < 20 nm (mainly UFP from aviation), but not with particles > 50 nm (mainly UFP from road traffic).
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UV-blootstelling bij industriële en medische toepassingenRijksinstituut voot Volksgezondheid en Milieu, 2020-05-01Deze brochure is bedoeld voor alle werknemers die werkzaamheden verrichten waarbij blootstelling aan ultraviolette (UV) straling kan optreden. In het bijzonder gaat het hierbij om ontsmetting van oppervlakken, water en lucht, UV-therapie, fluorescentieonderzoek, droogprocessen en overige grafische processen. De brochure is ook bedoeld voor de werkgever van deze werknemers en zijn preventiemedewerker. De brochure gaat alleen over de risico’s van UV-straling, niet over andere risico’s op de werkplek.
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Blootstelling aan laserstralingRijksinstituut voor Volksgezondheid en Milieu RIVM, 2020-05-01Deze brochure is bedoeld voor alle werknemers die werkzaamheden verrichten waarbij blootstelling aan laserstraling kan optreden. In het bijzonder gaat het hierbij om lasers die gebruikt worden bij bewerking van materialen, in de gezondheidszorg en in laboratoria. De brochure is ook bedoeld voor de werkgever van deze werknemers en zijn preventiemedewerker. De brochure gaat alleen over de risico’s van laserstraling, niet over andere risico’s op de werkplek.
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Infraroodstraling bij industriële toepassingen2020-05-01Deze brochure is bedoeld voor alle werknemers die werkzaamheden verrichten waarbij blootstelling aan infraroodstraling kan optreden. In het bijzonder gaat het hierbij om droogprocessen, smelten, gieten, walsen en spuiten van metaal en plastic en snijden door middel van verhitting. De brochure is ook bedoeld voor de werkgever van deze werknemers en zijn preventiemedewerker. De brochure gaat alleen over de risico’s van infraroodstraling, niet over andere risico’s op de werkplek.
