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Leusden, Netherlands

Tiktak A.,Netherlands Environmental Assessment Agency | Hendriks R.F.A.,Wageningen University | Boesten J.J.T.I.,Wageningen University | van der Linden A.M.A.,RIVM
Journal of Hydrology | Year: 2012

In the Netherlands, a spatially distributed version of the pesticide fate model PEARL is routinely used to assess the leaching potential of pesticides to groundwater. Recently, the model was modified to simulate the movement of pesticides to surface water. The peak concentration is considered to be the most important exposure endpoint for the ecotoxicological effect assessment for aquatic organisms. Macropore flow is an important driver for the peak concentration, so the leaching model PEARL was extended with a macropore module. Macropore parameters were derived from generally available soil data such as organic matter content and clay content using newly developed pedotransfer functions. These pedotransfer functions were constructed using a wide range of Dutch clayey soils. Results indicate a good correlation between these variables and soil structural parameters, which is due to the homogeneous mineralogical composition of Dutch clayey soils. Results of the spatially distributed modelling indicate that due to rapid transport through macropores, the concentration of pesticides in drainage water is generally higher in clayey soils than in light textured soils. In clayey soils, the boundary hydraulic conductivity and organic matter content were the most important drivers for the concentration in drainage water. Results further indicate that the concentration of pesticide in drainage water increases with increasing half-life and decreases with increasing sorption coefficient. However, the effect of these parameters is much less than obtained with the convection-dispersion equation because due to preferential flow most of the reactive part of the soil profile is bypassed. © 2012 Elsevier B.V. Source

To establish the prevalence of human echinococcosis in the Netherlands by using data from laboratories carrying out diagnostic procedures and data from pathology registries from 1997-2008. Descriptive. Data on serological diagnostic tests for Echinococcus granulosus carried out from 1997 to 2008 were gathered from the National Institute for Public Health and the Environment (RIVM) in Bilthoven and Leiden University Medical Center (LUMC). Additionally, all echinococcosis patients registered on the pathology database of the Dutch pathological anatomy national automated archive (PALGA) were analysed. A total of 7314 serum samples from 5125 patients were examined for antibodies. Cyst material from 39 patients was examined using molecular methods. The number of serum samples sent in annually was stable at 550 to 600. Over the period investigated, 1997-2008, on serological investigation a total of 485 patients were found to have a positive result on IgG-ELISA. Of these, the diagnosis of echinococcosis was confirmed in 445 patients by further serological investigation (on average 37 new patients each year (range: 19-59)) and/or a positive PCR result. Over the duration of the study period the number of new patients decreased from over 40 to fewer than 30 patients per year. Going by the family name, 95.5% of the 445 patients were probably imported cases of disease. In the Netherlands, echinococcosis is primarily seen as an imported disease with the majority of patients originating from areas around the Mediterranean Sea where it is endemic. Each year there are nearly 30 confirmed cases. Source

Dorne J.L.,Unit on Contaminants | Doerge D.R.,U.S. Food and Drug Administration | Vandenbroeck M.,Unit on Contaminants | Fink-Gremmels J.,University Utrecht | And 6 more authors.
Toxicology and Applied Pharmacology | Year: 2013

Melamine can be present at low levels in food and feed mostly from its legal use as a food contact material in laminates and plastics, as a trace contaminant in nitrogen supplements used in animal feeds, and as a metabolite of the pesticide cyromazine. The mechanism of toxicity of melamine involves dose-dependent formation of crystals with either endogenous uric acid or a structural analogue of melamine, cyanuric acid, in renal tubules resulting in potential acute kidney failure. Co-exposure to melamine and cyanuric acid in livestock, fish, pets and laboratory animals shows higher toxicity compared with melamine or cyanuric acid alone. Evidence for crystal formation between melamine and other structural analogs i.e. ammelide and ammeline is limited. Illegal pet food adulterations with melamine and cyanuric acid and adulteration of milk with melamine resulted in melamine-cyanuric acid crystals, kidney damage and deaths of cats and dogs and melamine-uric acid stones, hospitalisation and deaths of children in China respectively. Following these incidents, the tolerable daily intake for melamine was re-evaluated by the U.S. Food and Drug Administration, the World Health Organisation, and the Scientific Panel on Contaminants in the Food Chain of the European Food Safety Authority (EFSA). This review provides an overview of toxicology, the adulteration incidents and risk assessments for melamine and its structural analogues. Particular focus is given to the recent EFSA risk assessment addressing impacts on animal and human health of background levels of melamine and structural analogues in animal feed. Recent research and future directions are discussed. © 2012 Elsevier Inc. Source

Blanckaert P.,Scientific Institute of Public Health | Van Amsterdam J.G.C.,RIVM | Brunt T.M.,Trimbos institute | Van Den Berg J.D.J.,Netherlands Forensic Institute | And 3 more authors.
Journal of Psychopharmacology | Year: 2013

4-Methylamphetamine (4-MA) was originally developed as an appetite suppressant, but development was halted due to side effects. It has recently resurfaced as a new psychoactive substance in Europe, and is mostly found together with amphetamine. Around 11.5% of tested Dutch speed samples were positive for 4-MA. In Belgium, 4-MA was also found in speed samples. In 2011 and 2012, several fatal incidents after amphetamine use were observed in Belgium, the United Kingdom and The Netherlands. In all victims, toxicological analysis confirmed the presence of 4-MA, in addition to amphetamine. The observed blood amphetamine levels were too low to be fatal. Contrary to amphetamine, which displays noradrenergic and dopaminergic activity, 4-MA also shows serotonergic activity, which may contribute to the observed toxicity. Other mechanisms of toxicity are put forward in this paper as well. To conclude, the observed toxicity is most likely the result of the combined dopaminergic activity of amphetamine and the serotonergic activity of 4-MA. In addition, the presence of 4-MA may have dampened the psychoactive effects of amphetamine by attenuation of the amphetamine-induced dopamine release, potentially inclining users to ingest higher doses of contaminated speed. Also, slower metabolism of 4-MA and its MAO-inhibiting properties can also contribute to the unusual high toxicity of 4-MA. © The Author(s) 2013. Source

Viana M.,CSIC - Institute of Environmental Assessment And Water Research | Pey J.,CSIC - Institute of Environmental Assessment And Water Research | Querol X.,CSIC - Institute of Environmental Assessment And Water Research | Alastuey A.,CSIC - Institute of Environmental Assessment And Water Research | And 2 more authors.
Science of the Total Environment | Year: 2014

Atmospheric aerosols are emitted by natural and anthropogenic sources. Contributions from natural sources to ambient aerosols vary widely with time (inter-annual and seasonal variability) and as a function of the distance to source regions. This work aims to identify the main natural sources of atmospheric aerosols affecting air quality across Europe. The origin, frequency, magnitude, and spatial and temporal variability of natural events were assessed for the years 2008 and 2009. The main natural sources of atmospheric aerosols identified were African dust, sea spray and wildfires. Primary biological particles were not included in the present work. Volcanic eruptions did not affect air quality significantly in Europe during the study period. The impact of natural episodes on air quality was significant in Southern and Western Europe (Cyprus, Spain, France, UK, Greece, Malta, Italy and Portugal), where they contributed to surpass the PM10 daily and annual limit values. In Central and Northern Europe (Germany, Austria and Latvia) the impact of these events was lower, as it resulted in the exceedance of PM daily but not annual limit values. Contributions from natural sources to mean annual PM10 levels in 2008 and 2009 ranged between 1 and 2μg/m3 in Italy, France and Portugal, between 1 and 4μg/m3 in Spain (10μg/m3 when including the Canary Islands), 5μg/m3 in UK, between 3 and 8μg/m3 in Greece, and reached up to 13μg/m3 in Cyprus. The evaluation of the number of monitoring stations per country reporting natural exceedances of the daily limit value (DLV) is suggested as a potential tool for air quality monitoring networks to detect outliers in the assessment of natural contributions. It is strongly suggested that a reference methodology for the identification and quantification of African dust contributions should be adopted across Europe. © 2013 Elsevier B.V. Source

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