55 research outputs found
Exposure modelling in Europe : how to pave the road for the future as part of the European Exposure Science Strategy 2020-2030
Exposure models are essential in almost all relevant contexts for exposure science. To address the numerous challenges and gaps that exist, exposure modelling is one of the priority areas of the European Exposure Science Strategy developed by the European Chapter of the International Society of Exposure Science (ISES Europe). A strategy was developed for the priority area of exposure modelling in Europe with four strategic objectives. These objectives are (1) improvement of models and tools, (2) development of new methodologies and support for understudied fields, (3) improvement of model use and (4) regulatory needs for modelling. In a bottom-up approach, exposure modellers from different European countries and institutions who are active in the fields of occupational, population and environmental exposure science pooled their expertise under the umbrella of the ISES Europe Working Group on exposure models. This working group assessed the state-of-the-art of exposure modelling in Europe by developing an inventory of exposure models used in Europe and reviewing the existing literature on pitfalls for exposure modelling, in order to identify crucial modelling-related strategy elements. Decisive actions were defined for ISES Europe stakeholders, including collecting available models and accompanying information in a living document curated and published by ISES Europe, as well as a long-term goal of developing a best-practices handbook. Alongside these actions, recommendations were developed and addressed to stakeholders outside of ISES Europe. Four strategic objectives were identified with an associated action plan and roadmap for the implementation of the European Exposure Science Strategy for exposure modelling. This strategic plan will foster a common understanding of modelling-related methodology, terminology and future research in Europe, and have a broader impact on strategic considerations globally.Peer reviewe
The probabilistic aggregate consumer exposure model (PACEM): Validation and comparison to a lower-tier assessment for the cyclic siloxane D5
a b s t r a c t a r t i c l e i n f o Current practice of chemical risk assessment for consumer product ingredients still rarely exercises the aggregation of multi-source exposure. However, focusing on a single dominant source/pathway combination may lead to a significant underestimation of the risk for substances present in numerous consumer products, which often are used simultaneously. Moreover, in most cases complex multi-route exposure scenarios also need to be accounted for. This paper introduces and evaluates the performance of the Probabilistic Aggregate Consumer Exposure Model (PACEM) applied in the context of a tiered approach to exposure assessment for ingredients in cosmetics and personal care products (C&PCPs) using decamethylcyclopentasiloxane (D5) as a worked example. It is demonstrated that PACEM predicts a more realistic, but still conservative aggregate exposure within the Dutch adult population when compared to a deterministic point estimate obtained in a lower tier screening assessment. An overall validation of PACEM is performed by quantitatively relating and comparing its estimates to currently available human biomonitoring and environmental sampling data. Moderate (by maximum one order of magnitude) overestimation of exposure is observed due to a justified conservatism built into the model structure, resulting in the tool being suitable for risk assessment
The Development and Evaluation of a Probabilistic Model for Aggregate Exposure Assessment to Chemicals in Cosmetics and Personal Care Products
3D-Teknik : ett användbart hjälpmedel för möbelkonservering?
Föreliggande rapport syftar till att redogöra för hur olika 3D-tekniker kan fungera som praktiskt användbara hjälpmedel i arbeten rörande möbelkonservering och möbelrestaurering. Arbetet behandlar olika tekniker för att skanna och skriva ut, presenterar ett urval av tidigare forskning vilket berör det aktuella ämnet, samt ger inblick i praktiska fallstudier. Den tekniska utvecklingen av 3D-printing och skanning går stadigt framåt vilket väcker frågan om tekniken kan vara ett lämpligt hjälpmedel inom området för föremålsbevarande arbete. I arbetet presenteras ett antal fallstudier där 3D-tekniken har använts för dokumentation och restaurering av olika föremål. Teknikerna har sedan jämförts med konventionella metoder. PLA är ett utskriftsfilament, kanske främst avsett för kommersiellt bruk. I arbetet undersöks detta material och dess kompabilitet med andra material. Efter åldring genomgår materialet ett hållfasthets- och kulörtest. Resultaten visar att PLA kan vara känsligt för UV-strålning och temperaturer över 60°C. Vi anser att 3D-tekniken i flera fall kan fungera som ett användbart hjälpmedel för möbelkonservering.This thesis seeks to explain how the various 3D-technologies can serve as a practical aid in applied furniture conservation. The thesis deals with various techniques to scan and print, presents a selection of previous research relevant to the topic, and provides insight into the practical case studies. The technical development of 3D printing and scanning is advancing rapidly which raises the question whether the technology can be a useful tool in the field of conservation. The thesis presents a number of case studies where 3D technology has been used for documentation and restoration of various objects. These techniques have been compared with conventional methods. PLA is a printing fillament, perhaps primarily intended for commercial use. The work examines this material and its compatibility with other materials. After aging, the fillament undergoes a structural and color test. The results show that PLA is sensitive to UV-radiation and temperatures above 60°C. We believe that 3D technology can, in many cases, serve as a useful tool for furniture preservation
Concentrations of cyclic volatile methylsiloxanes in European cosmetics and personal care products: Prerequisite for human and environmental exposure assessment
Item does not contain fulltextLow molecular weight cyclic volatile methylsiloxanes (cVMSs) are widely employed as emollients and carrier solvents in personal care formulations in order to acquire desired performance benefits owing to their distinctive physicochemical properties. Under current European legislation cosmetic ingredients such as cVMSs are required to be labeled on the product package only qualitatively, while for the assessment of environmental and consumer exposure quantitative information is needed. The aim of this study was therefore to measure concentrations of three cVMSs, namely octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5) and dodecamethylcyclohexasiloxane (D6) in 51 cosmetics and personal care products (C&PCPs) that are currently available on the European market. The list of selected articles comprised a variety of hair and sun care products, skin creams and lotions, deodorants including antiperspirants, liquid foundations and a toothpaste. The target compounds were extracted from the products with different organic solvents dependent on the product matrix, followed by gas chromatography analysis with flame ionization detection (GC-FID). D5 was the predominant cVMS with the highest mean and median concentrations in all the C&PCP categories. The median concentrations of D5, D6 and D4 were 142, 2.3 and 0.053mg/g in deodorants/antiperspirants (n=11); 44.6, 30.0mg/g and below the limit of quantification (<LOQ; LOQ for D4=0.00071mg/g) in cosmetics (n=5); 8.4, 0.32mg/g and <LOQ in skin care (n=16); 9.6, 0.18 and 0.0055mg/g in hair care (n=10); and, 34.8, 0.53 and 0.0085mg/g in sun care (n=8) products, respectively. The calculated median aggregate daily dermal exposure to D4 and D5 from multiple C&PCPs was approximately 100 times lower than the current NOAEL derived from chronic inhalation rat studies
Usage patterns of personal care products: Important factors for exposure assessment
Contains fulltext :
111458.pdf (publisher's version ) (Closed access)Complete information regarding the use of personal care products (PCPs) by consumers is limited, but such information is crucial for realistic consumer exposure assessment. To fill this gap, a database was created with person-oriented information regarding usage patterns and circumstances of use for 32 different PCPs. Out of 2700 potential participants from the Netherlands, 516 men and women completed a digital questionnaire. The prevalence of use varied by gender, age, level of education and skin type. A high frequency of use was observed for some products (e.g. lip care products), while toothpaste, deodorant and day cream were generally used once or twice a day. The frequency of use for other PCPs varied over a wide range. The amounts of use varied largely between and within different product groups. Body lotion, sunscreen and after sun lotion were often applied on adjacent body parts. The majority of PCPs were applied in the morning, but some products, such as night cream and after sun, were predominantly applied in the evening or night. As expected, the participants used several PCPs simultaneously. The database yields important personalized exposure factors which can be used in aggregate consumer exposure assessment for substances that are components of PCPs
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