Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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    Anaerobic microbial processes for energy conservation and biotransformation of pollutants
    Luz Ferreira Martins Paulo, Lara da - \ 2017
    Wageningen University. Promotor(en): A.J.M. Stams, co-promotor(en): D.Z. Sousa. - Wageningen : Wageningen University - ISBN 9789463431125 - 234
    anaerobic microbiology - anaerobes - energy conservation - biotransformation - pollutants - heavy metals - sulfates (inorganic salts) - nickel - cobalt - methanosarcina barkeri - genomics - polymerase chain reaction - anaërobe microbiologie - anaërobe micro-organismen - energiebehoud - biotransformatie - verontreinigende stoffen - zware metalen - sulfaten (anorganische zouten) - nikkel - kobalt - methanosarcina barkeri - genomica - polymerase-kettingreactie

    Anaerobic microbial processes are commonly applied in the treatment of domestic and industrial wastewaters. Anaerobic digestion (AD) of wastewater has received a great deal of attention, but many aspects related to the complex interactions between microorganism, and how that is affected by the presence of certain toxic, are not yet fully understood. A particular case of this is the effect of heavy metals or chlorinated compounds. These compounds are known to have a strong impact in methanogens, a phylogenetic diverse group responsible for the last step of the AD process. The negative effect of sulphate towards methanogenesis is mainly related to outcompetition of methanogens by sulphate-reducing bacteria (SRB), or to toxicity caused by the sulphide generated from sulphate reduction. Heavy metals are part of many enzymes and cofactors and, in low concentrations, may beneficiate microbial activity. However, high concentrations of metals may disrupt enzyme function and structure. In cases where metal concentration is high, the presence of sulphate or sulphide might be favourable because sulphide precipitate with metals and detoxify the environment. In Chapter 2 we provide a review on the current knowledge on the effects of heavy metals and sulphate on AD, with special focus on methanogenesis. From this literature study, it came out that the influence of some metals, such as Co, is not extensively studied and that the potential of biologically produced sulphide as metal detoxification method in AD is still quite unexplored. In Chapter 3 we explored different strategies to improve methane production. Low concentrations of Ni and Co were supplemented to anaerobic sludge and the impact on methane production was evaluated. Although in contrast with other studies, no beneficial effect of metal supplementation was observed. Further on, the impact of high concentrations of Ni and Co added to anaerobic sludge was evaluated, as well as the use of sulphide as a detoxification strategy. This was evaluated in terms of impact on methane production and in changes in the microbial communities. The results showed that sulphide can be used as a method for metal detoxification, but in the case of biological produced sulphide, the competition between SRB and methanogens needs to be considered.

    Chlorinated compounds are widely used and commonly found in wastewaters. Several methanogenic metal-containing cofactors are reported to be involved in reductive dechlorination. Therefore, in Chapters 4 and 5 the potential of metal supplementation to enhance the dechlorination process was studied. In Chapter 4, the enrichment of methanogenic cultures able to perform reductive dechlorination of 1,2-dichloroethene (DCE) and tetrachlorethene (TCE) using different inoculum sources and substrates is described. Differences in physiological performance and in the microbial communities were evaluated. The results showed that the microbial community can be influenced by inoculum and substrate as well as by the chlorinated compound used. The enriched cultures presenting the best dechlorination performance were selected and used for metal supplementation studies with Ni, Co, and Fe. The results showed a clear positive impact of metal addition, both on methane production and reductive dechlorination. Further research on metal supplementation to enhance dechlorination was performed in pure cultures of Methanosarcina barkeri, a methanogen known to be able to reduce DCE (Chapter 5). In this case, it was observed that metal supplementation could improve methane production and reductive dechlorination, but the effect is dependent on the metal and concentration used. It was found that methanogenesis and reductive dechlorination can be affected in a different way by the same metal.

    Finally, in Chapter 6 the impact of sulphate on a methane-producing bioelectrochemical system (BES), an emerging technology that can be applied to wastewater treatment, was studied. The results showed an unexpected fast sulphate removal in the system and a limited impact caused by sulphate addition on methane production. The sulphate removal could only partially be explained by microbial activity, but the results demonstrated the ability of microbial communities to evolve and adapt to new operational conditions.

    In conclusion, the work presented in this thesis gave insights on the impact of heavy metals and sulphate in methanogenic systems. Furthermore, different approaches to maximise methane production were evaluated. In particular, it was shown that metal supplementation can be a promising strategy to improve anaerobic microbial processes, such as methanogenesis and reductive dechlorination.

    Risicobeoordeling van contaminanten in afval- en reststoffen bestemd voor gebruik als covergistingsmateriaal
    Ehlert, P.A.I. ; Wijnen, H.J. van; Struijs, J. ; Dijk, T.A. van; Schöll, L. van; Poorter, L.R.M. de - \ 2016
    Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-technical report 70) - 158
    biogas - co-vergisting - arsenicum - residuen - zware metalen - verontreinigende stoffen - pesticiden - biociden - mestbeleid - landbouwbeleid - organische verontreinigende stoffen - risicoschatting - biogas - co-fermentation - arsenic - residues - heavy metals - pollutants - pesticides - biocides - manure policy - agricultural policy - organic pollutants - risk assessment
    A number of wastes and by-products were reviewed for their suitability as substrates for co-digestion with animalmanure to produce biogas and a digestate for use as a fertiliser. The review included 21 substances proposed byLTO Noord (Dutch Farmers Union – Northern Netherlands) and Biogas Branche Organisatie (BBO, the Dutch BiogasIndustry Association) for inclusion in Annex Aa of the Fertiliser Act. At the request of the Ministry of EconomicAffairs a further 6 substances were added (21+6). In addition, 119 substances were re-reviewed in connection witha change to the reference composition for animal manure. The review focused on the possible adverseenvironmental effects of using the digestate as a fertiliser and followed the protocol for assessing the value andrisks of waste used as a fertiliser, version 2.1. The risk assessment included the inorganic contaminants (Cd, Cr, Cu,Hg, Ni, Pb, Zn, As) and organic contaminants (dioxine, PCBs, PAHs, mineral oil, residues of crop protectionproducts) as required by the Fertiliser Act. For all the wastes and by-products, data on composition were collectedfrom the literature and from analyses provided by stakeholders. Expert judgment was used where data were notavailable or were insufficient to conduct a risk assessment as prescribed by the protocol. Criteria for expertjudgment were developed for such situations. Two alternative risk assessment methods were developed for theresidues of pesticides and biocides, based partly on expert judgement. These methods were compared with themethod prescribed by the protocol. These three methods reflect different policy judgements; the protection level setby policymakers will determine which method should be used. The 21+6 substances were evaluated in accordancewith the protocol and using the three methods for evaluating the residues of pesticides and biocides. The resultswere compared with registered co-digestion materials in Flanders, Denmark and Germany. Recommendations aregiven to support policy decisions on the choice of alternative risk assessment method to be used to permit the codigestionof wastes and by-products in biogas production that produce an agronomically and environmentallyacceptable digestate for fertiliser use
    Ecophysiology and environmental distribution of organohalide-respiring bacteria
    Lu, Y. - \ 2016
    Wageningen University. Promotor(en): Hauke Smidt, co-promotor(en): Siavash Atashgahi. - Wageningen : Wageningen University - ISBN 9789462578418 - 239
    bacteria - halides - ecophysiology - phylogenetics - genomics - lakes - halogens - pollutants - bacteriën - haliden - ecofysiologie - fylogenetica - genomica - meren - halogenen - verontreinigende stoffen

    Organohalide-respiring bacteria (OHRB) are able to breathe natural and anthropogenically produced organohalides persistent in a broad range of oxygen-depleted environments. Therefore, these microorganisms are of high interest for organohalide-contaminated site bioremediation and natural halogen and carbon cycle. Nevertheless, to assess and adjust in situ bioremediation strategies and to enhance current understanding about the role of OHRB in natural habitats, thorough understanding of their ecophysiology and interaction with surrounding biotic and abiotic forces is necessary. To this end, this thesis focused on exploring ecophysiology and environmental distribution of OHRB in pristine and contaminated sites and unraveling their interactions with the co-existing microbial guilds in the community and geochemical parameters by application of a suite of physiological, molecular and geochemical analyses.

    Based on a comprehensive overview of currently known organohalide-respiring isolates and their environmental distribution, the presence of yet unknown OHRB in extreme environments was proposed as the known organohalide-respiring isolates survive/thrive at a moderate range of pH and salinity in laboratory culture. Therefore, the OHRB were surveyed in alkaline and hypersaline sediments collected from Lake Strawbridge, Western Australia, that was known to emit organohalides. As a result, for the first time, the dechlorination of chloroform and perchloroethene (PCE) to dichloromethane and trichloroethene, respectively, was documented from an alkaline hypersaline pristine environment.

    Corrinoids are essential cofactors for the activity of reductive dehalogenase enzymes. Ironically, some OHRB are reported to be corrinoid auxotrophs. Using transcriptional analysis and shotgun proteomics, here we show corrinoid auxotrophy in Dehalobacter restrictus PER-K23T. This detrimental deficiency seems to be compensated by up-regulation of relevant cobalamin salvaging and transport pathways to ensure sufficient corrinoid supply under partial corrinoid starvation. Hence, such OHRB incapable of de novo corrinoid synthesis will be dependent on non-dechlorinating community members to fulfill their nutritional needs indicating paramount importance of syntrophic interactions in supporting robust growth and activity of OHRB.

    Bacterial community analysis of chlorinated benzene dechlorinating consortia derived from contaminated harbour sludge suggested members of the Bacteroidetes phylum and Clostridiales order as well as sulfate-reducing Deltaproteobacteria as putative stimulating guilds that provide electron donor and/or organic cofactors to OHRB i.e. D. mccartyi and Dehalobacter. However, despite well-controlled lab condition, syntrophic interactions could be influenced by geochemical parameters under field settings. Accordingly, analysis of geochemical and microbial determinants of OHR at a site biostimulated by glycerol injection further verified supportive role of fermenters and sulfate reducers under highly reduced condition following biostimulation. However, towards the end of field experiment, reducing condition faded and sulfate increased concurrent with the appearance of Epsilonproteobacteria and Deferribacteres as putative oxidizers of reduced sulfur compounds. The latter guilds might serve as detoxifiers of sulfide and thereby stimulate D. mccartyi, but could also be inhibitory as successors of the more important syntrophic fermenting and sulfate reducing bacteria.

    In conclusion, this thesis expands our understanding of ecophysiology and environmental distribution of OHRB, addressing their presence in pristine environments as well as providing further evidence for their dependencies on other microbial community members in order to meet their nutritional requirements. Hence, research described here strengthens the scientific foundation for evaluating and optimizing strategies for the bioremediation of organohalide-contaminated sites and expands the natural niche of OHRB to extreme pristine environments.

    Beehold : the colony of the honeybee (Apis mellifera L) as a bio-sampler for pollutants and plant pathogens
    Steen, J.J.M. van der - \ 2016
    Wageningen University. Promotor(en): Huub Rijnaarts, co-promotor(en): Tim Grotenhuis; Willem Jan de Kogel. - Wageningen : Wageningen University - ISBN 9789462577510 - 206
    apis mellifera - honey bees - honey bee colonies - biological indicators - sampling - instruments - pollution - pollutants - heavy metals - plant pathogenic bacteria - erwinia amylovora - erwinia pyrifoliae - analytical methods - apis mellifera - honingbijen - honingbijkolonies - biologische indicatoren - bemonsteren - instrumenten (meters) - verontreiniging - verontreinigende stoffen - zware metalen - plantenziekteverwekkende bacteriën - erwinia amylovora - erwinia pyrifoliae - analytische methoden

    Bio-sampling is a function of bio-indication. Bio-indication with honeybee colonies (Apis mellifera L) is where the research fields of environmental technology and apiculture overlap. The honeybees are samplers of the environment by collecting unintentionally and simultaneously, along with nectar, pollen, water and honeydew from the flowers or on the leaves, other matter (in bio-indication terms: target matter) and accumulating this in the colony. Collected target matter, in this thesis heavy metals, the plant pathogens Erwinia pyrifoliae and Erwinia amylovora and the soil pollutant γ-HCH, is collected from the colony by subsampling. Subsampling the honeybee colony is done by taking and killing bees from the hive (sacrificial) or by collecting target matter from the bee’s exterior without killing the bee (non-sacrificial). In environmental technology terms the application of the honeybee colony is a Passive Sampling Method (PSM). In this thesis the possibilities and restrictions of the PSM honeybee colony are explored.

    Bio-indication is a broad research field with one common factor: a living organism (bio) is applied to record an alteration of the environment (indication). The environment may be small such as a laboratory or big such as an ecosystem. Alterations in the organism may vary from detecting substances foreign to the body to mortality of the organism. In environmental technology the concept Source-Path-Receptor (SPR) is applied to map the route of a pollutant. It describes where in the environment the pollution is, how it moves through the environment and where it ends. This environment is the same environment of all living organisms, ergo also honeybees. Honeybees depend on flowers for their food. In the SPR concept, a flower can be a source, path or receptor. Along with collecting pollen, nectar, water and honeydew, target matter is collected by honeybees. Each honeybee functions as a micro-sampler of target matter in the environment, in this case the flower. Each honeybee is part of a honeybee colony and in fact the honeybee colony is the bio-sampler. The honeybee colony is a superorganism. The well-being of the colony prevails over the individual honeybee. Food collection is directed by the colony’s need. Foragers are directed to the most profitable food sources by the bee dance and food exchange (trophallaxis). The result of this feature is that mainly profitable sources are exploited and poor food sources less or not at all. During the active foraging period hundreds to thousands of flowers are visited daily. The nectar, pollen, water and honeydew plus the unintentionally collected target matter is accumulated in the honeybee colony. In order to obtain target matter the colony must be subsampled. This is done by picking bees from the hive-entrance (hive-entering bees) or inside the hive (in-hive bees) and processing them for analysis (sacrificial). This is the most commonly applied method. However, it is possible to subsample the colony without picking and processing the bees by collecting target matter from the hive-entering bee’s exterior (non-sacrificial). For non-sacrificial subsampling of the honeybee colony the Beehold device with the sampling part Beehold tube has been developed. The results of bio-indication with honeybee colonies are qualitative and indicative for follow up study (Chapter 1).

    Six bio-indication studies with honeybee colonies for bio-indication of heavy metals, the plant pathogens Erwinia pyrifoliae and Erwinia amylovora and the soil pollutant γ-HCH are presented. Chapter 2 describes how the concentration of eighteen heavy metals in honeybees fluctuate throughout the period of July, August and September (temporal) at the study sites: the city of Maastricht, the urban location with an electricity power plant in Buggenum and along the Nieuwe Waterweg at Hoek van Holland (spatial). A number of the metals have not been previously analysed in honeybees. To study whether honeybees can be used for bio-indication of air pollution, the concentrations of cadmium, vanadium and lead were compared to concentrations found in honeybees. The honeybee colonies were placed next to the air samplers. Only significant differences of metal concentrations in the ambient air also show in honeybees. This was the case with vanadium in ambient air and honeybees. The spatial and temporal differences of cadmium and lead were too futile to demonstrate a correspondence (Chapter 3). In a national surveillance study in 2008 the concentration of eighteen metals in honeybees has been analysed. The results showed a distinct regional pattern. Honeybees in the East of the Netherlands have higher concentrations of heavy metals compared to the bees in the West. Besides regional differences local differences were also recorded. An approximate description of the land use around 148 apiaries (> 50% agriculture, > 50% wooded area, > 50% urban area and mixed use) indicated the impact of land use on metal concentrations in honeybees. In areas with > 50% wood significantly higher concentrations of heavy metals were detected (Chapter 4). Subsampling of the honeybee colonies in Chapter 2, 3 and 4 was done sacrificially. In the studies presented in Chapter 5, 6, and 7 the honeybee colonies were subsampled non-sacrificially or simultaneously non-sacrificially and sacrificially. The plant pathogen E. pyrifoliae causes a flower infection in the strawberry cultivation in greenhouses. In greenhouse strawberry cultivation honeybees are applied for pollination. In Chapter 5 the combination pollination / bio-indication by honeybee colonies is studied. This proved to be a match. E. pyrifoliae could be detected on in-hive bees prior to any symptom of the infection in the flowers. In the Beehold tube, the bacterium was detected at the same time as the first tiny symptoms of the infection. In Chapter 5 the principles on which the Beehold tube is based are presented and discussed. The plant pathogen E. amylovora causes fireblight in orchards. The combination pollination / bio-indication has also been applied in this study performed in Austria in 2013. It is known that E. amylovora can be detected on honeybees prior to any symptom in the flower or on the fruit tree. A fireblight outbreak depends on flowering period, humidity and temperature. In 2013 no fireblight infection emerged in the orchards where the study was performed. Therefore, the bacterium could not be detected on the honeybees. γ-HCH (Lindane) is one of the soil pollutants in the Bitterfeld region in Saxony-Anhalt in Germany. It is the result of dumping industrial waste around the production locations. Although γ-HCH is bound to soil particles there is a flux to groundwater and surface water. Consequently, the pollution may end up in the sediments of the streambed and flood plains. The study objective was to investigate the hypothetic route of γ-HCH from polluted soil (source), via soil erosion and atmospheric deposition (route) to the receptor (flowering flowers) by detecting γ-HCH in the Beehold tube. Although on average over 17000 honeybees passed through the Beehold tube daily for a maximal period of 28 days, no γ-HCH has been detected. The pollen pattern in the Beehold tube revealed where the bees collected the food (Chapter 7).

    The application of the honeybee colony has pros and cons. Distinctive pros are many micro samplers, the extensive collection of matter (both food and target matter) and the accumulation in the colony. For successful bio-indication with honeybee colonies, determining factors are: the target matter, location of the target matter, distance between target matter and the honeybee colony, individual or pooled subsampling, the minimal sampling frequency and sample size, and sacrificial or non-sacrificial subsampling applied solely or in combination. Taking bees from a colony impacts upon the colony’s performance and consequently the passive sampling method. Based on a long-years’ experience and inter-collegial discussion it is stated that 3% of the forager bees (hive-entering) and 1.5% of the in-hive bees can be sampled safely without impacting upon the colony. This restriction does not apply when carrying out non-sacrificial subsampling of the honeybee colony (Chapter 8).

    Performing bio-indication with honeybee colonies has more applications than have been exploited so far. Further research can make a change. In particular I mention here the combination of pollination and bio-indication and the application of non-sacrificial subsampling solely or in combination with sacrificial subsampling.

    Everywhere Apiculture is practiced (all over the world except the polar areas) bio-indication with honeybee colonies can be applied in a simple, practical and low cost way.

    Impact of the water matrix on the effect and the side effect of MP UV/H2O2 treatment for the removal of organic micropollutants in drinking water production
    Martijn, A.J. - \ 2015
    Wageningen University. Promotor(en): Ivonne Rietjens, co-promotor(en): J.P. Malley; J.C. Kruithof. - Wageningen : Wageningen University - ISBN 9789462575882 - 172
    water treatment - pollutants - toxins - pretreatment - drinking water - pressure treatment - ultraviolet radiation - hydrogen peroxide - effects - waterzuivering - verontreinigende stoffen - toxinen - voorbehandeling - drinkwater - drukbehandeling - ultraviolette straling - waterstofperoxide - effecten
    Removal of micropollutants in source separated sanitation
    Butkovskyi, A. - \ 2015
    Wageningen University. Promotor(en): Huub Rijnaarts; Grietje Zeeman, co-promotor(en): L. Hernández Leal. - Wageningen : Wageningen University - ISBN 9789462574168 - 189
    verontreinigende stoffen - verontreiniging - waterverontreiniging - afvalwater - stedelijk afvalwater - volksgezondheidsbevordering - waterzuivering - verwijdering - geneesmiddelen - farmaceutische producten - antibioticumresiduen - residuen - pollutants - pollution - water pollution - waste water - municipal wastewater - sanitation - water treatment - removal - drugs - pharmaceutical products - antibiotic residues - residues
    Source separated sanitation is an innovative sanitation method designed for minimizing use of energy and clean drinking water, and maximizing reuse of water, organics and nutrients from waste water. This approach is based on separate collection and treatment of toilet wastewater (black water) and the rest of the domestic wastewater (grey water). Different characteristics of wastewater streams facilitate recovery of energy, nutrients and fresh water. To ensure agricultural or ecological reuse of liquid and solid products of source separated sanitation, the quality of these materials has to meet (future) standards, i.e. for micropollutant concentrations. Therefore the objectives of this thesis included assessment of micropollutant content of source separated sanitation products intended for resource recovery and examination of post-treatment technologies for micropollutant mitigation within source separated sanitation
    Screening van hot spots van nieuwe verontreinigingen : een pilot studie in bodem, grondwater en oppervlaktewater
    Lahr, J. ; Laak, T.L. ter; Derksen, A. - \ 2014
    Wageningen : Alterra (Alterra-rapport 2538) - 87
    bodemverontreiniging - waterverontreiniging - verontreinigende stoffen - toxicologie - geneesmiddelen - ecologische risicoschatting - biotesten - inventarisaties - soil pollution - water pollution - pollutants - toxicology - drugs - ecological risk assessment - bioassays - inventories
    Onder nieuwe verontreinigingen verstaan we stoffen die nog niet of niet volledig zijn gereguleerd en waarvan de milieurisico’s vaak onbekend zijn. Daarbij gaat het om stoffen als natuurlijke hormonen en hormoonverstorende stoffen (weekmakers, detergenten, brandvertragers, e.d.), humane geneesmiddelen, diergeneesmiddelen, nanodeeltjes en microplastics. In de ‘waterwereld’ is altijd meer aandacht besteed aan de nieuwe verontreinigingen dan binnen andere beleidsvelden. In de bodem zijn de aanwezigheid en de mogelijke risico’s grotendeels onbekend. In 2013 heeft een consortium van diverse onderzoeksinstanties en stakeholders een pilotonderzoek uitgevoerd naar de aanwezigheid en mogelijke risico’s van hormonen en geneesmiddelen in het systeem bodem - grondwater - oppervlaktewater.
    Leaching of inorganic contaminants towards groundwater : impact assessment of the Dutch Soil Quality Decree on Groundwater
    Spijker, J. ; Groenenberg, J.E. ; Comans, R.N.J. ; Dijkstra, J.J. - \ 2013
    Bilthoven : RIVM - 201
    grondwaterverontreiniging - bodemverontreiniging - uitspoelen - metalen - halfmetalen - verontreinigende stoffen - modelleren - anorganische verbindingen - groundwater pollution - soil pollution - leaching - metals - semimetals - pollutants - modeling - inorganic compounds
    Dit rapport beschrijft de opzet, evaluatie en resultaten van een modellering van uitloging van metalen en metalloïden uit bodems naar het grondwater. Deze studie had de volgende doelen: 1. het bepalen van representatieve concentraties van metalen en metalloïden in het ondiepe (eerste meter) grondwater; 2. het bepalen van representatieve waarden voor bodemparameters, die de uitloging van metalen en metalloïden bepalen, zoals reactiviteit van opgelost organische koolstof, gehalten aan oxiden en reactiviteit van metalen en metalloïden; 3. het verbeteren van het bestaande modelinstrumentarium voor het modelleren van de uitloging van metalen en metalloïden uit de bodem, inclusief de onzekerheid van deze modellen.
    Proficiency test for dioxins and dioxin-like PCBs in fats
    Elbers, I.J.W. ; Traag, W.A. - \ 2013
    Wageningen : Rikilt - Institute of Food Safety (RIKILT-report 2013.017) - 113
    diervoeding - veevoeder - plantaardige vetten - dioxinen - polychloorbifenylen - voederveiligheid - tests - verontreinigende stoffen - toxische stoffen - voersamenstelling - animal nutrition - fodder - plant fats - dioxins - polychlorinated biphenyls - feed safety - tests - pollutants - toxic substances - feed formulation
    The test provides an evaluation of the methods applied for quantification of dioxins and dioxin-like PCBs in fat by the laboratories. The proficiency test was organised according to ISO 17043. For this test, four samples were prepared: - sunflower oil spiked with dioxins and PCBs; - sunflower oil mixed with contaminated fish oil; - sunflower oil mixed with contaminated chicken fat and spiked with 2,3,7,8-PCDF; - sunflower oil mixed with contaminated chicken fat and spiked with non-dioxin like PCBs.
    Transport and degradation of contaminants in the vadose zone
    Schotanus, D. - \ 2013
    Wageningen University. Promotor(en): Sjoerd van der Zee, co-promotor(en): Martine van der Ploeg. - S.l. : s.n. - ISBN 9789461735850 - 125
    uitspoelen - transportprocessen - besmetters - verontreinigende stoffen - grondwater - bodemeigenschappen - degradatie - leaching - transport processes - contaminants - pollutants - groundwater - soil properties - degradation

    Leaching of contaminants from the vadose zone to the groundwater depends on the soil properties and the infiltration rate. In this thesis, organic degradable contaminants were studied, such as de-icing chemicals (consisting of propylene glycol, PG) and pesticides. Heterogeneous soil properties lead to spatial variability in leaching, which is particularly important for degradable contaminants. The infiltration rate determines the travel time in the vadose zone, and thus the time available for degradation.

    Two field experiments were performed with a multi-compartment sampler (consisting of 10 x 10 cells of 3.15 x 3.15 cm2each) to examine the dependence of spatial variability in contaminant leaching on the infiltration rate. The first experiment was carried out during the snowmelt period, characterized by high infiltration rates from snowmelt. The second experiment was carried out with irrigation to mimic homogeneous rainfall. The preferential flow paths were similar for both experiments. With a high infiltration rate during the snowmelt experiment, the leaching was distributed more homogeneous than during the irrigation experiment. Therefore, it is concluded that the soil heterogeneity is mainly caused by spatial differences in the soil hydraulic properties, and not by macropores. The leached masses of the degradable PG and a nondegradable tracer were highly correlated. At the scale of the experiment, heterogeneous infiltration resulting from spatial differences in snowmelt did not have much influence on the flow and solute paths.

    The results from the field experiment were used to parameterize a random field for the scaling factor of the retention curve. As a criterion to compare the results from simulations and observations, the sorted and cumulative total drainage in a cell was used. The effect of the ratio of the infiltration rate over the degradation rate on leaching of degradable solutes was investigated. Furthermore, the spatial distribution of the leaching of degradable and non-degradable solutes was compared. The infiltration rate influences contaminant leaching in two ways. Firstly, the travel time of the contaminant in the vadose zone depends on the infiltration rate. Secondly, the fraction of the soil which is active in transport is influenced by the infiltration rate. As a result, the spatial distribution of contaminant leaching, and therefore the leached fraction, depends on the infiltration rate.

    The leached fraction of a degradable contaminant is often estimated from average soil properties and stationary weather series. For contaminants that degrade in both the adsorbed and aqueous phase, it is known how these averaged properties should be derived from heterogeneous properties. However, for contaminants that only degrade in the aqueous phase, this is not well known. In soils that are layered with respect to the adsorption constant, the propagation of the contaminant plume, and thus the travel time in the vadose zone, depends on the adsorption constant, degradation rate, and dispersivity. Regarding variable weather series, seasonal fluctuations in precipitation lead to large differences in travel times in a dry climate, and thus large differences in the leached fraction, especially for contaminants with little adsorption. In a wet climate, the effect of such seasonal fluctuations is diminished.

    In the vadose zone, PG can be degraded by micro-organisms, for which electron-acceptors are needed. A field experiment showed that aerobic as well as anaerobic degradation occurs in the vadose zone. For anaerobic degradation, manganese-oxides (which are present in the soil) or nitrate (applied to enhance biodegradation) can be used as electron-acceptors. Reduced forms of manganese can be transported to the groundwater, and thus the soil could be depleted from manganese-oxides. A model was developed in which both types of degradation were included. The application of nitrate did not lead to a lower PG leaching, or in a slower depletion of manganese-oxides. The leached fraction is higher with a thick snowcover and high meltrate, as then PG is transported rapidly in the soil. Snowmelt did not result in anaerobic soil, despite the high soil moisture content, and thus low oxygen diffusion.

    Risicobeoordeling van contaminanten in afval- en reststoffen bestemd voor gebruik als covergistingsmateriaal
    Ehlert, P.A.I. ; Wijnen, H.J. van; Struijs, J. ; Dijk, T.A. van; Schöll, L. van; Poorter, L.R.M. de - \ 2013
    Wageningen : Wettelijke Onderzoekstaken Natuur & Milieu (WOt-werkdocument 333) - 168
    mestverwerking - co-vergisting - verontreinigende stoffen - digestaat - zware metalen - pesticiden - milieubeleid - monitoring - manure treatment - co-fermentation - pollutants - digestate - heavy metals - pesticides - environmental policy - monitoring
    Een beoordeling is uitgevoerd van 21 stoffen die door LTO-Noord en de Biogas Branche Organisatie (BBO) aangemeld zijn voor opname in bijlage Aa van de Uitvoeringsregeling Meststoffenwet. Op verzoek van het ministerie EZ zijn daar 6 stoffen aan toegevoegd (21+6) en werden 119 eerder aangemelde stoffen herbeoordeeld. De beoordeling betreft met name de milieuhygienische consequenties van het gebruik van covergistingsmaterialen en het resulterende digestaat na vergisting. De beoordeling van de zware metaal- en arseengehalten en de door de Meststoffenwet aangewezen organische microverontreinigingen volgt het Protocol Beoordeling Stoffen eststoffenwet, versie 2.1. Expert judgement is toegepast in geval gegevens niet of niet volledig beschikbaar waren om dit protocol te kunnen toepassen. Criteria voor expert judgement zijn voor deze situatie opgesteld. Voor de beoordeling van de residuen van gewasbeschermingsmiddelen en biociden zijn drie alternatieve systematieken opgesteld, mede gebaseerd op toepassing van expert judgement. Het na te streven beschermingsniveau bepaalt welke systematiek gebruikt zal gaan worden. De 21+6 stoffen zijn beoordeeld volgens het protocol en opgestelde alternatieven. De toelating van covergistingsmaterialen in Vlaanderen, Denemarken en Duitsland is betrokken bij de beoordeling. Tenslotte worden aanbevelingen gedaan om te komen tot beleidsafwegingen en –keuzes inzake opgestelde alternatieven en tot een effectief protocol voor toelating van afval- en reststoffen als covergistingsmateriaal.
    Actieve biologische Monitoring Zoete Rijkswateren: microverontreinigingen in quaggamosselen - 2011
    Glorius, S.T. ; Kotterman, M.J.J. - \ 2012
    Den Helder : IMARES (Rapport / IMARES Wageningen UR C055/12) - 55
    waterkwaliteit - oppervlaktewater - waterverontreiniging - verontreinigende stoffen - water quality - surface water - water pollution - pollutants
    Sinds 2007 wordt melding gemaakt van het voorkomen van quaggamosselen (Dreissena bugensis) in het IJsselmeergebied (RWS, 2009). Uit verschillende karteringsonderzoeken naar het mosselbestand blijkt dat het aandeel quaggamosselen in de mosselbanken de afgelopen jaren vanuit het zuidelijke gedeelte van het IJsselmeergebied sterk in aantallen toeneemt. Een toekomstige verdrijving van de driehoeksmossel door de quaggamossel is dan ook niet uit te sluiten.
    Removal of micropollutants from aerobically treated grey water via ozone and activated carbon
    Hernandez Leal, L. ; Temmink, B.G. ; Zeeman, G. ; Buisman, C.J.N. - \ 2011
    Water Research 45 (2011)9. - ISSN 0043-1354 - p. 2887 - 2896.
    afvalwaterbehandeling - waterzuivering - verontreinigende stoffen - verwijdering - afvalwater - aërobe behandeling - ozon - actieve kool - processors - vergelijkend onderzoek - waste water treatment - water treatment - pollutants - removal - waste water - aerobic treatment - ozone - activated carbon - processors - comparative research - endocrine-disrupting chemicals - waste-water - uv filters - organic-compounds - bisphenol-a - in-vitro - pharmaceuticals - ozonation - products - vivo
    Ozonation and adsorption onto activated carbon were tested for the removal micropollutants of personal care products from aerobically treated grey water. MilliQ water spiked with micropollutants (100–1600 µgL-1) was ozonated at a dosing rate of 1.22. In 45 min, this effectively removed (>99%): Four parabens, bisphenol-A, hexylcinnamic aldehyde, 4-methylbenzylidene-camphor (4MBC), benzophenone-3 (BP3), triclosan, galaxolide and ethylhexyl methoxycinnamate. After 60 min, the removal efficiency of benzalkonium chloride was 98%, tonalide and nonylphenol 95%, octocrylene 92% and 2-phenyl-5-benzimidazolesulfonic acid (PBSA) 84%. Ozonation of aerobically treated grey water at an applied ozone dose of 15 mgL-1, reduced the concentrations of octocrylene, nonylphenol, triclosan, galaxolide, tonalide and 4-methylbenzylidene-camphor to below limits of quantification, with removal efficiencies of at least 79%. Complete adsorption of all studied micropollutants onto powdered activated carbon (PAC) was observed in batch tests with milliQ water spiked with 100–1600 µgL-1 at a PAC dose of 1.25 gL-1 and a contact time of 5 min. Three granular activated carbon (GAC) column experiments were operated to treat aerobically treated grey water. The operation of a GAC column with aerobically treated grey water spiked with micropollutants in the range of 0.1–10 µgL-1 at a flow of 0.5 bed volumes (BV)h-1 showed micropollutant removal efficiencies higher than 72%. During the operation time of 1728 BV, no breakthrough of TOC or micropollutants was observed. Removal of micropollutants from aerobically treated grey water was tested in a GAC column at a flow of 2 BVh-1. Bisphenol-A, triclosan, tonalide, BP3, galaxolide, nonylphenol and PBSA were effectively removed even after a stable TOC breakthrough of 65% had been reached. After spiking the aerobically treated effluent with micropollutants to concentrations of 10–100 µgL-1, efficient removal to below limits of quantification continued for at least 1440 BV. Both ozonation and adsorption are suitable techniques for the removal of micropollutants from aerobically treated grey water.
    Actieve biologische Monitoring Zoete Rijkswateren: microverontreinigingen in driehoeksmosselen - 2010
    Glorius, S.T. ; Kotterman, M.J.J. - \ 2011
    IJmuiden : IMARES (Rapport / IMARES Wageningen UR C058/11) - 52
    waterkwaliteit - oppervlaktewater - waterverontreiniging - verontreinigende stoffen - rivieren - biologische monitoring - oppervlaktewaterkwaliteit - water quality - surface water - water pollution - pollutants - rivers - biomonitoring - surface water quality
    In het kader van de Biologische Monitoring Zoete Rijkswateren is in 2010 een actieve biologische monitoring (ABM) onderzoek uitgevoerd met driehoeksmosselen (Dreissena polymorpha) in een aantal zoete Rijkswateren. Het betreft de uitvoering van het deelproject "Microverontreinigingen in driehoeksmosselen 2010”. In dit rapport worden de analyseresultaten van het monitorprogramma besproken evenals het resultaat van een extra eenmalig onderzoek naar het effect van verwatering. Voor de actieve biologische monitoring werden driehoeksmosselen afkomstig van een relatief schone locatie (Zeughoek, IJsselmeer) gedurende zes weken uitgezet in de te monitoren locaties waarvan men inzicht wil hebben in het gehalte aan microverontreinigingen in het oppervlaktewater.
    Nieuwe inzichten tijdens congres over waterkwaliteitbeleid
    Schipper, P.N.M. ; Schoumans, O.F. ; Bannink, A. - \ 2010
    H2O : tijdschrift voor watervoorziening en afvalwaterbehandeling 43 (2010)22. - ISSN 0166-8439 - p. 12 - 13.
    waterkwaliteit - waterbeleid - verontreinigende stoffen - waterverontreiniging - conferenties - water quality - water policy - pollutants - water pollution - conferences
    In Canada vergaderde de International Water Association (IWA) onlangs over de voortgang van de aanpak van diffuse bronnen, die de waterkwaliteit bedreigen. Ook vanuit Nederland was een delegatie aanwezig.
    Update BCF's in Sedisoil
    Kotterman, M.J.J. ; Heuvel-Greve, M.J. van den - \ 2010
    IJmuiden : IMARES (Rapport / IMARES Wageningen UR C142/10) - 14
    verontreinigende stoffen - literatuur - oppervlaktewater - opname van contaminanten - computational science - nederlandse wateren - oppervlaktewaterkwaliteit - pollutants - literature - surface water - contaminant uptake - computational science - dutch waters - surface water quality
    In het Sedisoil programma wordt het risico van contaminanten voor de mens berekend. Belangrijke parameters in deze berekening zijn de BCF waarden voor de contaminanten. Als de concentratie van een bepaalde contaminant in water bekend is, kan met behulp van de BioConcentratie Factor (BCF) de concentratie in de vis geschat worden. BCF waarden zijn lastig te bepalen en de BCF’s uit de literatuur kunnen sterk verschillen. Er zijn daarom ook theoretische rekenmodellen ontwikkeld om BCF waarden te berekenen. Op verzoek van RWS zijn BCF waarden voor diverse contaminanten, relevant voor de Nederlandse oppervlaktewateren, in de literatuur opgezocht. Indien naast BCF waarden ook goed omschreven BAF (bioaccumulatie factor) of BSAF (biota sediment accumulatie factor) waarden zijn gevonden zijn die ook meegenomen.
    Removal of micropollutants from grey water : combining biological and physical/chemical processes
    Hernandez Leal, L. - \ 2010
    Wageningen University. Promotor(en): Cees Buisman, co-promotor(en): Grietje Zeeman; Hardy Temmink. - [S.l. : S.n. - ISBN 9789085857013 - 181
    afvalwaterbehandeling - verontreinigende stoffen - biodegradatie - anaërobe afbraak - biochemisch zuurstofverbruik - chemisch zuurstofverbruik - uitvlokking - desinfectie - nieuwe sanitatie - waste water treatment - pollutants - biodegradation - anaerobic digestion - biochemical oxygen demand - chemical oxygen demand - flocculation - disinfection - new sanitation
    Grey water consists of the discharges from kitchen sinks, showers, baths, washing machines and hand basins. The amount of grey water produced per person in The Netherlands is about 90 Ld-1, accounting for up to 75 % of the wastewater volume produced by households, and over 90 % if vacuum toilets are installed. Grey water is relatively low in pollution and therefore, after appropriate treatment, has great potential for reuse in non-potable applications such as infiltration, irrigation, toilet flushing, laundry water, etc. The goal of this thesis was to develop a treatment concept for grey water to exploit its reuse potential. A special focus of this thesis was set on the study of organic micropollutants from personal care and household chemicals. Grey water (from 32 houses in Sneek, The Netherlands) contains, on average, 724-150 mgL-1 of chemical oxygen demand (COD), 27-12 mgL-1 of total nitrogen, 7.2-4.2 mgL-1 of phosphorus and 41-12 mgL-1 of anionic surfactants. The high biodegradability of grey water (70-5 %) indicated the possibility of recovering COD as methane. Biological treatment of grey water was conducted in three systems, aerobic, anaerobic and combined anaerobic + aerobic, at a total hydraulic retention time (HRT) of 12-13 hours at 32 °C. Aerobic treatment in a sequencing batch reactor resulted in COD removal of 90 %, which was significantly higher than 51 % removal by anaerobic treatment in an upflow anaerobic sludge blanket (UASB) reactor. Grey water treatment in a combined anaerobic + aerobic system resulted in a COD removal efficiency of 89 %. The application of a UASB reactor for the pre-treatment of grey water yielded a small amount of energy. Therefore, the aerobic system was preferred for grey water treatment. Bioflocculation of grey water in a high loaded membrane bioreactor was tested as alternative to aerobic treatment. The concentrated grey water of this process can potentially increase the methane yield by 73 % within ‘new sanitation' concepts. Eighteen compounds of personal care products and household chemicals (UV- filters, fragrances, preservatives, biocides, surfactants) were measured in grey water at low gL-1 levels. During biological treatment most of these compounds were partially removed. In general, the treatment in the aerobic system lead to the highest removal efficiencies of these compounds, where biodegradation and adsorption to sludge were the most likely removal mechanisms. However, the UV-filters PBSA and EHMC and the fragrance tonalide were poorly removed in the tested biological systems. Although reuse standards for these compounds do not exist, the post-reatment of aerobically treated effluent was recommended prior to reuse. Adsorption on activated carbon and ozonation were proven effective as post-treatment options for grey water.
    Biologische Monitoring Zoete Rijkswateren: microverontreinigingen in driehoeksmosselen - 2009
    Glorius, S.T. ; Kotterman, M.J.J. - \ 2010
    IJmuiden : IMARES (Rapport / IMARES Wageningen UR C057/10) - 38
    waterkwaliteit - oppervlaktewater - waterverontreiniging - verontreinigende stoffen - rivieren - biologische monitoring - oppervlaktewaterkwaliteit - water quality - surface water - water pollution - pollutants - rivers - biomonitoring - surface water quality
    In het kader van de Biologische Monitoring Zoete Rijkswateren is in 2009 een actieve biologische monitoring (ABM) onderzoek uitgevoerd met driehoeksmosselen (Dreissena polymorpha) in een aantal zoete Rijkswateren. Het betreft een uitvoering van het deelproject "Microverontreinigingen in driehoeksmosselen 2006-2009” dat in opdracht van Rijkswaterstaat Waterdienst (voorheen RIZA) Lelystad wordt uitgevoerd door IMARES te IJmuiden. In dit rapport worden de analyseresultaten besproken van 2009 en een korte beschouwing gegeven van de gehele onderzoeksperiode. Voor de actieve biologische monitoring werden driehoeksmosselen afkomstig van een relatief schone locatie (Zeughoek, IJsselmeer) gedurende zes weken uitgezet in de te monitoren locaties waarvan men inzicht wil hebben in het gehalte aan microverontreinigingen in het oppervlaktewater.
    Fate of the estrogen nonylphenol in river sediment: availability, mass transfer and biodegradation
    Weert, J.P.A. de - \ 2009
    Wageningen University. Promotor(en): Huub Rijnaarts, co-promotor(en): Alette Langenhoff; Tim Grotenhuis. - [S.l. : S.n. - ISBN 9789085854661 - 143
    verontreinigde sedimenten - rivieren - bodemverontreiniging - verontreinigende stoffen - oestrogenen - waterorganismen - biodegradatie - aquatische toxicologie - bodemsanering - contaminated sediments - rivers - soil pollution - pollutants - oestrogens - aquatic organisms - biodegradation - aquatic toxicology - soil remediation
    Veel riviersedimenten zijn in het verleden verontreinigd geraakt met estrogene verbindingen, die toxische effecten kunnen veroorzaken op aquatische organismen, zoals de vervrouwlijking van mannelijke vissen. Een van deze estrogene verbindingen is nonylfenol (NP). Nonylfenol is een organische verbinding die bestaat uit een fenolgroep met een lineaire of een vertakte keten van negen koolstofatomen. Voornamelijk mengsels van vertakte NP-isomeren komen voor als verontreiniging in het milieu. Sedimenten die verontreinigd zijn met NP kunnen functioneren als secundaire bron van verontreiniging van het rivierwater, waar het toxische effecten kan veroorzaken op aquatische organismen. Het risico van toxische effecten door NP, dat aanwezig is in het sediment, wordt bepaald door de beschikbaarheid van NP in het sediment, het massatransport vanuit het sediment naar het rivierwater en de mogelijkheid voor biologische afbraak van NP in het sediment of het rivierwater.
    Contaminant release from sediments: a mass flux approach
    Smit, M.P.J. - \ 2009
    Wageningen University. Promotor(en): Wim Rulkens; Tim Grotenhuis. - [S.l. : S.n. - ISBN 9789085854586 - 120
    sediment - overstromingen - dieldrin - verontreinigende stoffen - stroming - waterstroming - deeltjes - verdunning - waterverontreiniging - organische verontreinigende stoffen - verontreinigde sedimenten - sediment - floods - dieldrin - pollutants - flow - water flow - particles - dilution - water pollution - organic pollutants - contaminated sediments
    With the predicted climate change it is expected that the chances of flooding increase. During flood events sediments will suspend and if sediments are polluted, contaminants can be released to water. Also under gentle flow regimes, when sediments are settled and form a sediment bed, transfer of contaminants to water is possible. The release of contaminants from the sediment –particles and bed– to the aqueous phase is the first step in a sequence of processes. When this step is the rate limiting process we speak of mass transfer limitation. In this thesis the release of (mainly) dieldrin from field aged sediment was studied using the SPEED reactor we developed for this purpose. In this reactor parameters like mixing intensity and water flow –or dilution– rate can be controlled and low aqueous concentrations of contaminants can be quantified. Dieldrin release from the sediments was assessed for different situations: simulating a flood event and simulating more gentle flow conditions. In line with the variable discharge rates in rivers, we performed experiments with different flow rates and assessed the release of dieldrin in time.
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