Institute for Risk Assessment science IRAS

Utrecht, Netherlands

Institute for Risk Assessment science IRAS

Utrecht, Netherlands
SEARCH FILTERS
Time filter
Source Type

Boogaard H.,Institute for Risk Assessment science IRAS | Kos G.P.A.,Energy Research Center of the Netherlands | Weijers E.P.,Energy Research Center of the Netherlands | Janssen N.A.H.,Institute for Public Health and the Environment RIVM | And 4 more authors.
Atmospheric Environment | Year: 2011

Policies to reduce outdoor air pollution concentrations are often assessed on the basis of the regulated pollutants. Whether these are the most appropriate components to assess the potential health benefits is questionable, as other health-relevant pollutants may be more strongly related to traffic. The aim of this study is to compare the contrast in concentration between major roads and (sub)urban background for a large range of pollutants and to analyze the magnitude of the measured difference in the street - background for major streets with different street configurations. Measurements of PM10, PM2.5, particle number concentrations (PNC), black carbon (BC), elemental composition of PM10 and PM2.5 and NOx were conducted simultaneously in eight major streets and nine (sub)urban background locations in the Netherlands. Measurements were done six times for a week during a six month period in 2008. High contrasts between busy streets and background locations in the same city were found for chromium, copper and iron (factor 2-3). These elements were especially present in the coarse fraction of PM. In addition, high contrasts were found for BC and NOx (factor 1.8), typically indicators of direct combustion emissions. The contrast for PNC was similar to BC. NO2 contrast was lower (factor 1.5). The largest contrast was found for two street canyons and two streets with buildings at one side of the street only. The contrast between busy streets and urban background in NO2 was less than the contrast found for BC, PNC and elements indicative of non-exhaust emissions, adding evidence that NO2 is not representing (current) traffic well. The study supports a substantial role for non-exhaust emissions including brake- and tyre wear and road dust in addition to direct combustion emissions. Significant underestimation of disease burden may occur when relying too much on the regulated components. © 2010 Elsevier Ltd.


Grant
Agency: Narcis | Branch: Project | Program: Completed | Phase: Agriculture | Award Amount: | Year: 2008

1. To define the applicability domain of EST by testing a series of selected relevant classes of chemicals.2. To improve the prediction model of the EST on the basis of the results of testing the chemical classes as mentioned above and on the basis of the biology of the model.3. To enhance the predictivity and extrapolation to the human by investigating the possibility to use alternative differentiation routes and existing human stem cell lines.4. To feed the project outcome into the scientific community and into international regulatory bodies that deal with testing strategies and guidelines (EU, OECD) The Embryonic Stem cell Test (EST) is the most extensively studied animal-free alternative for developmental toxicity testing. Current experience with the EST indicates that the applicability domain and the prediction model require further study before implementation of EST in testing strategies can be considered. We will test a series of selected classes of compounds which are of relevance in view of existing knowledge on their developmental toxicity profile. Using the data generated, the prediction model will be improved, and the optimal place of EST in the reproductive toxicity testing strategy defined.In addition, a parallel approach is aimed at improvement of the predictivity of the test in the long term by exploring alternative stem cell differentiation routes and by using existing human rather than murine ES cell lines. Finally, the outcome will be continuously communicated in existing international bodies such as EU and OECD to promote implementation of the updated EST in international testing strategies.


PubMed | McGill University, Lyon University Hospital Center, University Paris - Sud, University of Paris Descartes and 5 more.
Type: Journal Article | Journal: Revue des maladies respiratoires | Year: 2015

The EGEA study (epidemiological study on the genetics and environment of asthma, bronchial hyperresponsiveness and atopy), which combines a case-control and a family-based study of asthma case (n=2120subjects) with three surveys over 20years, aims to identify environmental and genetic factors associated with asthma and asthma-related phenotypes. We summarize the results of the phenotypic characterization and the investigation of environmental and genetic factors of asthma and asthma-related phenotypes obtained since 2007in the EGEA study (42articles).Both epidemiological and genetic results confirm the heterogeneity of asthma. These results strengthen the role of the age of disease onset, the allergic status and the level of disease activity in the identification of the different phenotypes of asthma. The deleterious role of active smoking, exposure to air pollution, occupational asthmogenic agents and cleaning products on the prevalence and/or activity of asthma has been confirmed. Accounting for gene-environment interactions allowed the identification of new genetic factors underlying asthma and asthma-related traits and better understanding of their mode of action.The EGEA study is contributing to the advances in respiratory research at the international level. The new phenotypic, environmental and biological data available in EGEA study will help characterizing the long-term evolution of asthma and the factors associated to this evolution.


Rava M.,Center for Research in Epidemiology and Population Health | Rava M.,University Paris - Sud | Smit L.A.M.,Institute for Risk Assessment science IRAS | Nadif R.,Center for Research in Epidemiology and Population Health | Nadif R.,University Paris - Sud
Current Opinion in Allergy and Clinical Immunology | Year: 2015

Purpose of Review: Asthma is a complex disease characterized by an intricate interplay of both heritable and environmental factors. Understanding the mechanisms through which genes and environment interact represents one of the major challenges for pulmonary researchers. This review provides an overview of the recently published literature on gene-environment (G×E) interactions in asthma, with a special focus on the new methodological developments in the postgenomewide association studies (GWAS) era. Recent Findings: Most recent studies on G×E interaction in asthma used a candidate-gene approach. Candidate-gene studies considering exposure to outdoor air pollutants showed significant interactions mainly with variants in the GSTP1 gene on asthma in children. G×E studies on passive and active smoking, including one genomewide interaction study, identified novel genes of susceptibility to asthma and a time-dependent effect of maternal smoking. Other recent studies on asthma found interactions between candidate genes and occupational allergen exposure and several domestic exposures such as endotoxin and gas cooking. New methods were developed to efficiently estimate G×E interaction in GWAS, and a pathway-based strategy to select an enriched gene-set for G×E studies has recently been proposed. Summary: The G×E studies presented in this review offer a good example on how candidate-gene approaches can complement and help in validating GWAS findings. © 2015 Wolters Kluwer Health, Inc. All rights reserved.


Font-Ribera L.,Center for Research in Environmental Epidemiology | Font-Ribera L.,IMIM Hospital del Mar Medical Research Institute | Font-Ribera L.,University Pompeu Fabra | Font-Ribera L.,CIBER ISCIII | And 28 more authors.
Environmental Research | Year: 2016

Background: Trihalomethanes (THMs) in exhaled breath and trichloroacetic acid (TCAA) in urine are internal dose biomarkers of exposure to disinfection by-products (DBPs) in swimming pools. Objective: We assessed how these biomarkers reflect the levels of a battery of DBPs in pool water and trichloramine in air, and evaluated personal determinants. Methods: A total of 116 adults swam during 40 min in a chlorinated indoor pool. We measured chloroform, bromodichloromethane, dibromochloromethane and bromoform in exhaled breath and TCAA in urine before and after swimming, trichloramine in air and several DBPs in water. Personal determinants included sex, age, body mass index (BMI), distance swum, energy expenditure, heart rate and 12 polymorphisms in GSTT1, GSTZ1 and CYP2E1 genes. Results: Median level of exhaled total THMs and creatinine adjusted urine TCAA increased from 0.5 to 14.4 μg/m3 and from 2.5 to 5.8 μmol/mol after swimming, respectively. The increase in exhaled brominated THMs was correlated with brominated THMs, haloacetic acids, haloacetonitriles, haloketones, chloramines, total organic carbon and total organic halogen in water and trichloramine in air. Such correlations were not detected for exhaled chloroform, total THMs or urine TCAA. Exhaled THM increased more in men, urine TCAA increased more in women, and both were affected by exercise intensity. Genetic variants were associated with differential increases in exposure biomarkers. Conclusion: Our findings suggest that, although affected by sex, physical activity and polymorphisms in key metabolizing enzymes, brominated THMs in exhaled breath could be used as a non-invasive DBP exposure biomarker in swimming pools with bromide-containing source waters. This warrants confirmation with new studies. © 2016 Elsevier Inc.


Grant
Agency: Narcis | Branch: Project | Program: Completed | Phase: Physics, Chemistry and Medicine | Award Amount: | Year: 2007

The main goal of this project is to find a proper measure of exposure characterising extremely low frequency (ELF) and radiofrequency (RF) exposure, for usage in epidemiological studies to define high vs low exposed persons or in human experimental studies to use realistic every (whole) day exposure values. Exposure occurs at different spatial and temporal levels: micro-, meso- and macro-level. In order to compare exposure at these levels a measure of exposure should be defined at each level. Preferably, the measure of exposure is expressed as a single number.The secondary goal is to build an exposure classification system, for instance by means of an Activity Exposure Matrix (AEM), which couples an activity to a level of exposure. The AEM is filled with the single digit characterisation based on personal exposimeter data. Ideally, in future research the exposure can be estimated based on a combination of this AEM and a questionnaire, without the need to actually measure. Or it can be used in epidemiological studies to select suitable contrast (high-low exposed) activities and groups of persons performing these activities.An additional aim is the creation of a database/inventory of the current exposure situation in the Netherlands. This database is preferably an extension of the current RIVM GIS system containing the major transmitters for radio and TV and the base stations.To achieve the project s goal the following research questions are formulated:1. What is a proper measure of exposure, based on measurements?2. What activities lead to high and what activities to low exposure?3. Can a questionnaire on activity patterns discriminate between high and low exposed groups?4. What is the exposure contrast in the Netherlands? Exposure characterisation is an essential part of research into the possible health effects due to exposure of radiofrequency electromagnetic fields. Because the mechanism which describes the steps from exposure to possible health effect is unknown, the relevant measure of exposure is also unknown. This project contributes to the development of tools and models that allow a better characterisation of exposure in epidemiological studies and in specific work situations. The project also gives a better insight into what characteristics of exposure are important and how they are represented in the populations studied. This project intends to develop methods to produce valid estimates of exposure due to sources in the living environment, like mobile phone base stations (GSM, DCS and UMTS) and sources used close to individuals (mobile phone, DECT and Wifi) and due to several sources in the workplace. The main goal of this project is to find a proper measure of exposure characterising extremely low frequency (ELF) and radiofrequency (RF) exposure, for usage in epidemiological studies to define high vs low exposed persons or in human experimental studies to use realistic every (whole) day exposure values. Exposure occurs at different spatial and temporal levels: micro-, meso- and macro-level. In order to compare exposure at these levels a measure of exposure should be defined at each level. Preferably, the measure of exposure is expressed as a single digit.The secondary goal is to build an exposure classification system, for instance by means of an Activity Exposure Matrix (AEM), which couples an activity to a level of exposure. The AEM is filled with the single digit characterisation based on personal exposimeter data. Ideally, in future research the exposure can be estimated based on a combination of this AEM and a questionnaire, without the need to actually measure. Or it can be used in epidemiological studies to select suitable contrast (high-low exposed) activities and groups of persons performing these activities.An additional aim is the creation of a database/inventory of the current exposure situation in the Netherlands. This database is preferably an extension of the current RIVM GIS system containing the ma


Grant
Agency: Narcis | Branch: Project | Program: Completed | Phase: Physics, Chemistry and Medicine | Award Amount: | Year: 2002

The PIAMA birt cohort study has started in 1996 in order to study the effect of the application of mite-impermeable mattress covers and pillowcases over a period of 8 years. A second aim was studying the etiology of allergy and asthma in relation to several risk factors. By the end of 2001 the children have been monitored over a period of 4 years. The intervention has resulted in a demonstrable reduction of the exposure to house dust mite allergen. Clinical differences have not yet been found, but these were not expected during the first years of life. This porposal aims at a continued monitoring of the children when they are 5 and 6 years of age. Questionnaires will be distributed in 2002 and 2003. Attention will be paid to issues that have already been examined (airway symptoms, allergy, lifestyle factors, environmental factors). To some items more attention will be paid, e.g. the continued use (or reasons for stopping use) of covers, quality of life, and use of health care and medicines. Attention will also be paid to further data processing and reporting on the data collected until the age of 4.


Forns J.,Norwegian Institute of Public Health | Mandal S.,Norwegian Institute of Public Health | Iszatt N.,Norwegian Institute of Public Health | Polder A.,Norwegian University of Life Sciences | And 5 more authors.
Environmental Research | Year: 2016

Background The aim of this study was to assess the association between postnatal exposure to multiple persistent organic pollutants (POPs) measured in breast milk samples and early behavioral problems using statistical methods to deal with correlated exposure data. Methods We used data from the Norwegian HUMIS study. We measured concentrations of 24 different POPs in human milk from 612 mothers (median collection time: 32 days after delivery), including 13 polychlorinated biphenyls (PCB) congeners, 6 polybrominated diphenyl ethers (PBDE) congeners and five organochlorine compounds. We assessed child behavioral problems at 12 and 24 months using the infant toddler symptom checklist (ITSC). Higher score in ITSC corresponds to more behavioral problems. First we performed principal component analysis (PCA). Then two variable selection methods, elastic net (ENET) and Bayesian model averaging (BMA), were applied to select any toxicants associated with behavioral problems. Finally, the effect size of the selected toxicants was estimated using multivariate linear regression analyses. Results p,p′-DDT was associated with behavioral problems at 12 months in all the applied models. Specifically, the principal component composed of organochlorine pesticides was significantly associated with behavioral problems and both ENET and BMA identified p,p′-DDT as associated with behavioral problems. Using a multiple linear regression model an interquartile increase in p,p′-DDT was associated with a 0.62 unit increase in ITSC score (95% CI 0.45, 0.79) at 12 months, corresponding to more behavioral problems. The association was modified by maternal education: the effect of p,p′-DDT was strongest in women with lower education (β=0.59; 95%CI: 0.38, 0.81) compared to the mother with higher education (β=0.14; 95%CI: −0.05, 0.34) (p-value for interaction=0.089). At 24 months, neither selection method consistently identified any toxicant associated with behavioral problems. Conclusion Within a mixture of 24 toxicants measured in breast milk, p,p′-DDT was the single toxicant associated with behavioral problems at 12 months using different methods for handling numerous correlated exposures. © 2016 Elsevier Inc.


Josquin N.M.,Wageningen University | Linssen J.P.H.,Institute for Risk Assessment science IRAS | Houben J.H.,Wageningen University | Houben J.H.,Institute for Risk Assessment science IRAS
Meat Science | Year: 2012

Dutch-style fermented sausages were manufactured with 15% and 30% pork back-fat substitution by pure or commercial encapsulated fish oil, either added as such or as pre-emulsified mixture with soy protein isolate. Adding commercial encapsulated fish oil was the most important factor influencing the chemical composition. The fat content was not significantly different between products (p> 0.05). The n-6/. n-3 ratio decreased from 8.49 in controls to 0.90-2.47 in modified products. Lipid oxidation parameters (propanal and hexanal) showed much higher values for sausages with pure fish oil than for products with encapsulated oil. For the latter, lipid oxidation was similar to controls. Products with encapsulated or pre-emulsified oil were significantly firmer than products from other treatments in physical and sensory analysis (p< 0.05). Overall, it is technologically feasible to enrich dry fermented sausages with n-3 fatty acids from fish oil and the application of commercial encapsulated fish oil seems to be the best in retaining overall quality. © 2011 Elsevier Ltd.


Grant
Agency: Narcis | Branch: Project | Program: Completed | Phase: Agriculture | Award Amount: | Year: 2007

None

Loading Institute for Risk Assessment science IRAS collaborators
Loading Institute for Risk Assessment science IRAS collaborators