The use of adverse outcome pathways in the safety evaluation of food additives
Vinken, Mathieu ; Kramer, Nynke ; Allen, Timothy E.H. ; Hoffmans, Yvette ; Thatcher, Natalie ; Levorato, Sara ; Traussnig, Heinz ; Schulte, Stefan ; Boobis, Alan ; Thiel, Anette ; Rietjens, Ivonne M.C.M. - \ 2020
Archives of Toxicology 94 (2020). - ISSN 0340-5761
Adverse outcome pathway - Food additive - Safety evaluation
In the last decade, adverse outcome pathways have been introduced in the fields of toxicology and risk assessment of chemicals as pragmatic tools with broad application potential. While their use in the pharmaceutical and cosmetics sectors has been well documented, their application in the food area remains largely unexplored. In this respect, an expert group of the International Life Sciences Institute Europe has recently explored the use of adverse outcome pathways in the safety evaluation of food additives. A key activity was the organization of a workshop, gathering delegates from the regulatory, industrial and academic areas, to discuss the potentials and challenges related to the application of adverse outcome pathways in the safety assessment of food additives. The present paper describes the outcome of this workshop followed by a number of critical considerations and perspectives defined by the International Life Sciences Institute Europe expert group.
Characterizing the coverage of critical effects relevant in the safety evaluation of food additives by AOPs
Kramer, Nynke I. ; Hoffmans, Yvette ; Wu, Siyao ; Thiel, Anette ; Thatcher, Natalie ; Allen, Timothy E.H. ; Levorato, Sara ; Traussnig, Heinz ; Schulte, Stefan ; Boobis, Alan ; Rietjens, Ivonne M.C.M. ; Vinken, Mathieu - \ 2019
Archives of Toxicology 93 (2019)8. - ISSN 0340-5761 - p. 2115 - 2125.
3Rs - Acceptable daily intake - Adverse outcome pathway - Critical adverse effect - Food additives
There is considerable interest in adverse outcome pathways (AOPs) as a means of organizing biological and toxicological information to assist in data interpretation and method development. While several chemical sectors have shown considerable progress in applying this approach, this has not been the case in the food sector. In the present study, safety evaluation reports of food additives listed in Annex II of Regulation (EC) No 1333/2008 of the European Union were screened to qualitatively and quantitatively characterize toxicity induced in laboratory animals. The resulting database was used to identify the critical adverse effects used for risk assessment and to investigate whether food additives share common AOPs. Analysis of the database revealed that often such scrutiny of AOPs was not possible or necessary. For 69% of the food additives, the report did not document any adverse effects in studies based on which the safety evaluation was performed. For the remaining 31% of the 326 investigated food additives, critical adverse effects and related points of departure for establishing health-based guidance values could be identified. These mainly involved effects on the liver, kidney, cardiovascular system, lymphatic system, central nervous system and reproductive system. AOPs are available for many of these apical endpoints, albeit to different degrees of maturity. For other adverse outcomes pertinent to food additives, including gastrointestinal irritation and corrosion, AOPs are lacking. Efforts should focus on developing AOPs for these particular endpoints.
Representativeness errors in comparing chemistry transport and chemistry climate models with satellite UV-Vis tropospheric column retrievals
Boersma, K.F. ; Vinken, G.C.M. ; Eskes, H.J. - \ 2016
Geoscientific Model Development 9 (2016)2. - ISSN 1991-959X - p. 875 - 898.
Ultraviolet-visible (UV-Vis) satellite retrievals of trace gas columns of nitrogen dioxide (NO2), sulfur dioxide (SO2), and formaldehyde (HCHO) are useful to test and improve models of atmospheric composition, for data assimilation, air quality hindcasting and forecasting, and to provide top-down constraints on emissions. However, because models and satellite measurements do not represent the exact same geophysical quantities, the process of confronting model fields with satellite measurements is complicated by representativeness errors, which degrade the quality of the comparison beyond contributions from modelling and measurement errors alone. Here we discuss three types of representativeness errors that arise from the act of carrying out a model-satellite comparison: (1) horizontal representativeness errors due to imperfect collocation of the model grid cell and an ensemble of satellite pixels called superobservation, (2) temporal representativeness errors originating mostly from differences in cloud cover between the modelled and observed state, and (3) vertical representativeness errors because of reduced satellite sensitivity towards the surface accompanied with necessary retrieval assumptions on the state of the atmosphere. To minimize the impact of these representativeness errors, we recommend that models and satellite measurements be sampled as consistently as possible, and our paper provides a number of recipes to do so. A practical confrontation of tropospheric NO2 columns simulated by the TM5 chemistry transport model (CTM) with Ozone Monitoring Instrument (OMI) tropospheric NO2 retrievals suggests that horizontal representativeness errors, while unavoidable, are limited to within 5-10 % in most cases and of random nature. These errors should be included along with the individual retrieval errors in the overall superobservation error. Temporal sampling errors from mismatches in cloud cover, and, consequently, in photolysis rates, are of the order of 10 % for NO2 and HCHO, and systematic, but partly avoidable. In the case of air pollution applications where sensitivity down to the ground is required, we recommend that models should be sampled on the same mostly cloud-free days as the satellite retrievals. The most relevant representativeness error is associated with the vertical sensitivity of UV-Vis satellite retrievals. Simple vertical integration of modelled profiles leads to systematically different model columns compared to application of the appropriate averaging kernel. In comparing OMI NO2 to GEOS-Chem NO2 simulations, these systematic differences are as large as 15-20 % in summer, but, again, avoidable.
|Test slavinken - Verre van verse vinken
Beumer, Rijkelt - \ 2015
Ships going slow in reducing their NOx emissions : Changes in 2005-2012 ship exhaust inferred from satellite measurements over Europe
Boersma, K.F. ; Vinken, G.C.M. ; Tournadre, J. - \ 2015
Environmental Research Letters 10 (2015)7. - ISSN 1748-9326 - 10 p.
Weaddress the lack of temporal information on ship emissions, and report on rapid short-term variations of satellite-derived shipNOx emissions between 2005 and 2012 over European seas. Our inversion is based onOMI observed troposphericNO2 columns and GEOS-Chem simulations. Average European shipNOx emissions increased by~15% from 2005 to 2008. This increase was followed by a reduction of~12% in 2009, a direct result of the global economic downturn in 2008–2009, and steady emissions from 2009 to 2012. Observations of ship passages through the Suez Canal and satellite altimeter derived ship densities suggests that ships in the Mediterranean Sea have reduced their speed by more than 30% since 2008. This reduction in ship speed is accompanied by a persistent 45% reduction of average, per shipNOx emission factors. Our results indicate that the practice of ‘slow steaming’, i.e. the lowering of vessel speed to reduce fuel consumption, has indeed been implemented since 2008, and can be detected from space. In spite of the implementation of slow steaming, one in seven of allNOx molecules emitted in Europe in 2012 originated from the shipping sector, up from one in nine in 2005. The growing share of the shipping contributions to the overall EuropeanNOx emissions suggests a need for the shipping sector to implement additional measures to reduce pollutant emissions at rates that are achieved by the road transport and energy producing sectors in Europe.
Worldwide biogenic soil NOx emissions inferred from OMI NO2 observations
Vinken, G.C.M. ; Boersma, K.F. ; Maasakkers, J.D. ; Adon, M. ; Martin, R.V. - \ 2014
Atmospheric Chemistry and Physics 14 (2014). - ISSN 1680-7316 - p. 10363 - 10381.
nitric-oxide emissions - ozone monitoring instrument - atmospheric trace gases - tropospheric no2 - nitrogen-oxides - satellite-observations - united-states - global inventory - n2o emissions - geos-chem
Biogenic NOx emissions from soils are a large natural source with substantial uncertainties in global bottom-up estimates (ranging from 4 to 15 Tg N yr-1). We reduce this range in emission estimates, and present a top-down soil NOx emission inventory for 2005 based on retrieved tropospheric NO2 columns from the Ozone Monitoring Instrument (OMI). We use a state-of-science soil NOx emission inventory (Hudman et al., 2012) as a priori in the GEOS-Chem chemistry transport model to identify 11 regions where tropospheric NO2 columns are dominated by soil NOx emissions. Strong correlations between soil NOx emissions and simulated NO2 columns indicate that spatial patterns in simulated NO2 columns in these regions indeed reflect the underlying soil NOx emissions. Subsequently, we use a mass-balance approach to constrain emissions for these 11 regions on all major continents using OMI observed and GEOS-Chem simulated tropospheric NO2 columns. We find that responses of simulated NO2 columns to changing NOx emissions are suppressed over low NOx regions, and account for these non-linearities in our inversion approach. In general, our approach suggests that emissions need to be increased in most regions. Our OMI top-down soil NOx inventory amounts to 10.0 Tg N for 2005 when only constraining the 11 regions, and 12.9 Tg N when extrapolating the constraints globally. Substantial regional differences exist (ranging from -40% to +90%), and globally our top-down inventory is 4–35% higher than the GEOS-Chem a priori (9.6 Tg N yr-1). We evaluate NO2 concentrations simulated with our new OMI top-down inventory against surface NO2 measurements from monitoring stations in Africa, the USA and Europe. Although this comparison is complicated by several factors, we find an encouraging improved agreement when using the OMI top-down inventory compared to using the a priori inventory. To our knowledge, this study provides, for the first time, specific constraints on soil NOx emissions on all major continents using OMI NO2 columns. Our results rule out the low end of reported soil NOx emission estimates, and suggest that global emissions are most likely around 12.9 ± 3.9 Tg N yr-1.
Constraints on ship NOx emissions in Europe using GEOS-Chem and OMI satellite NO2 observations
Vinken, G.C.M. ; Boersma, K.F. ; Donkelaar, A. van; Zhang, W. - \ 2014
Atmospheric Chemistry and Physics 14 (2014). - ISSN 1680-7316 - p. 1353 - 1369.
ozone monitoring instrument - nitrogen-oxide emissions - marine boundary-layer - tropospheric no2 - interannual variability - power-plants - global-model - inventories - retrieval - columns
We present a top-down ship NOx emission inventory for the Baltic Sea, the North Sea, the Bay of Biscay and the Mediterranean Sea based on satellite-observed tropospheric NO2 columns of the Ozone Monitoring Instrument (OMI) for 2005–2006. We improved the representation of ship emissions in the GEOS-Chem chemistry transport model, and compared simulated NO2 columns to consistent satellite observations. Relative differences between simulated and observed NO2 columns have been used to constrain ship emissions in four European seas (the Baltic Sea, the North Sea, the Bay of Biscay and the Mediterranean Sea) using a mass-balance approach, and accounting for nonlinear sensitivities to changing emissions in both model and satellite retrieval. These constraints are applied to 39% of total top-down European ship NOx emissions, which amount to 0.96 TgN for 2005, and 1.0 TgN for 2006 (11–15% lower than the bottom-up EMEP ship emission inventory). Our results indicate that EMEP emissions in the Mediterranean Sea are too high (by 60 %) and misplaced by up to 150 km, which can have important consequences for local air quality simulations. In the North Sea ship track, our top-down emissions amount to 0.05 TgN for 2005 (35% lower than EMEP). Increased top-down emissions were found for the Baltic Sea and the Bay of Biscay ship tracks, with totals in these tracks of 0.05 TgN (131% higher than EMEP) and 0.08 TgN for 2005 (128% higher than EMEP), respectively. Our study explicitly accounts for the (non-linear) sensitivity of satellite retrievals to changes in the a priori NO2 profiles, as satellite observations are never fully independent of model information (i.e. assumptions on vertical NO2 profiles). Our study provides for the first time a space-based, top-down ship NOx emission inventory, and can serve as a framework for future studies to constrain ship emissions using satellite NO2 observations in other seas.
Comparing environmental consequences of anaerobic mono- and co-digestion of pig manure to produce bio-energy – A life cycle perspective
Vries, J.W. de; Vinken, T.M.W.J. ; Hamelin, L. ; Boer, I.J.M. de - \ 2012
Bioresource Technology 125 (2012). - ISSN 0960-8524 - p. 239 - 248.
emissions - bioenergy - systems
The aim of this work was to assess the environmental consequences of anaerobic mono- and co-digestion of pig manure to produce bio-energy, from a life cycle perspective. This included assessing environmental impacts and land use change emissions (LUC) required to replace used co-substrates for anaerobic digestion. Environmental impact categories considered were climate change, terrestrial acidification, marine and freshwater eutrophication, particulate matter formation, land use, and fossil fuel depletion. Six scenarios were evaluated: mono-digestion of manure, co-digestion with: maize silage, maize silage and glycerin, beet tails, wheat yeast concentrate (WYC), and roadside grass. Mono-digestion reduced most impacts, but represented a limited source for bio-energy. Co-digestion with maize silage, beet tails, and WYC (competing with animal feed), and glycerin increased bio-energy production (up to 568%), but at expense of increasing climate change (through LUC), marine eutrophication, and land use. Co-digestion with wastes or residues like roadside grass gave the best environmental performance
|Berichten van het Buys Ballot herfstsymposium 2011
Banda, N. ; Derendorp, L. ; Lacagnina, C. ; Theeuwes, N.E. ; Vinken, G. ; Steeneveld, G.J. - \ 2012
Meteorologica / Nederlandse Vereniging van Beroeps Meteorologen 21 (2012)1. - ISSN 0929-1504 - p. 24 - 26.
Slaan uw vinken al?
Bron, W.A. - \ 2011
Wageningen : Nature Today
Ideologie ontmoet economie; Private investeringen in Nederlands bos, natuur en landschap
Vinken, M. ; Hoogstra, M.A. - \ 2011
Vakblad Natuur Bos Landschap 8 (2011)1. - ISSN 1572-7610 - p. 27 - 29.
natuurbeleid - investering - ecosysteemdiensten - nature conservation policy - investment - ecosystem services
Meer investeringen van burgers en bedrijven in bos, natuur en landschap. Dat is wat de overheid graag wil. Private investeringen komen echter nauwelijks van de grond, ondanks de vele verschillende initiatieven om deze te stimuleren. De vraag die we ons daarom moeten stellen, is of private financiering überhaupt wel toekomst heeft. Wageningen Universiteit deed daarom onderzoek naar de motieven van verschillende private partijen om wel of niet in bos, natuur en landschap te investeren. Via streekrekening, landschapsveilingen en groene financiering
Grote waternavels, exotische penseelkrabben en dramatisch weinig vlinders
Vliet, A.J.H. van - \ 2009
Vakblad Natuur Bos Landschap 6 (2009)3. - ISSN 1572-7610 - p. 30 - 31.
fenologie - flora - fauna - veldwerk - phenology - flora - fauna - field work
Met het slaan van de vinken en de in bloei komende krokussen lijkt begin maart toch eindelijk lente 2009 aan te breken. Dat is even anders dan direct voorgaande jaren. In het record vroege 2008 was de natuur 6 weken eerder. Terwijl de laatste winter zich het best laat vergelijken met een gemiddelde winter van 20 jaar geleden. Enkele feitjes uit het huidige voorjaar: over de lynx in Limburg, de dood van zwemkrabben, grote waternavels als onkruid
The lignan macromolecule from flaxseed : structure and bioconversion of lignans
Struijs, K. - \ 2008
Wageningen University. Promotor(en): Harry Gruppen, co-promotor(en): J.P. Vinken. - [S.l.] : S.n. - ISBN 9789085852476 - 179
lignanen - lijnzaad - chemische samenstelling - fermentatie - sesamzaad - bioactieve verbindingen - lignans - linseed - chemical composition - fermentation - sesame seed - bioactive compounds
Flaxseeds are known already for a long time for their positive health effects. The high content of dietary fiber, the advantageous fatty acid composition and the lignans are held responsible for this. Lignans are compounds, which have a similar structure as human estradiol. As a result of that, they are expected to influence hormone metabolism, and (beneficially) influence human health. However, the lignans from flaxseed are not bioactive themselves. They need to be bioactivated by the bacteria in the human intestinal tract. Firstly, it was investigated how lignans are present in flaxseed. Lignans were found to form oligomeric molecules together with other components. These oligomeric molecules are called the lignan macromolecule. Secondly, it was investigated, which microorganisms are involved in the bioconversion reaction and we isolated the formed bioactive lignans. Via this procedure bioactive lignans has been obtained, which can be used as a functional food ingredient.
|Feasability of the UASB-process for the treatment of low strength wastes
Lettinga, G. ; Vinken, J.N. - \ 1980
In: Proceedings 35th Ind. Waste Conf., Purdue University, 1980