Gehalten van gebromeerde vlamvertragers (PBDE's) in mengmonsters van Nederlandse voedingsmiddelen

Geen rapportnummer in publicatie.In Nederland wordt de blootstelling aan PolyBroom DifenylEthers (PBDE's) uit voeding berekend door metingen te combineren met voedselconsumptiegegevens (de Mul et al., 2005; Winter-Sorkina et al., 2006; Bakker et al., 2008). Daartoe zijn in 2006 voedingsmiddelen als vis, zuivel, groenten, etc. verzameld en op PBDE's onderzocht. Vraag hierbij was of de toegepaste analytisch-chemische methode, die eigenlijk voor 24-uurs duplicaat voeding ontwikkeld is (Zeilmaker et al., 2008), ook op deze specifieke voedingsmiddelen toegepast kan worden. Deze rapportage beschrijft de toepassing van de meetmethode voor PBDE's in 24-uurs duplicaatvoeding op (meng)monsters van specifieke voedingsmiddelen anno 2006. Voor de volledigheid zijn de gehalten zoals die in 2003/2004 in vergelijkbare mengmonsters gemeten zijn (de Mul et al., 2005) als aparte bijlage in deze rapportage opgenomen.VW

Depression during pregnancy: views on antidepressant use and information sources of general practitioners and pharmacists

<p>Abstract</p> <p>Background</p> <p>The use of antidepressants during pregnancy has increased in recent years. In the Netherlands, almost 2% of all pregnant women are exposed to antidepressants. Although guidelines have been developed on considerations that should be taken into account, prescribing antidepressants during pregnancy is still a subject of debate. Physicians and pharmacists may have opposing views on using medication during pregnancy and may give contradictory advice on whether or not to take medication for depression and anxiety disorders during pregnancy. In this study, we investigated information sources used by general practitioners (GPs) and pharmacists and their common practices.</p> <p>Methods</p> <p>A questionnaire on the use of information sources and the general approach when managing depression during pregnancy was sent out to 1400 health care professionals to assess information sources on drug safety during pregnancy and also the factors that influence decision-making. The questionnaires consisted predominantly of closed multiple-choice questions.</p> <p>Results</p> <p>A total of 130 GPs (19%) and 144 pharmacists (21%) responded. The most popular source of information on the safety of drug use during pregnancy is the Dutch National Health Insurance System Formulary, while a minority of respondents contacts the Dutch national Teratology Information Service (TIS). The majority of GPs contact the pharmacy with questions concerning drug use during pregnancy. There is no clear line with regard to treatment or consensus between GPs on the best therapeutic strategy, nor do practitioners agree upon the drug of first choice. GPs have different views on stopping or continuing antidepressants during pregnancy or applying alternative treatment options. The debate appears to be ongoing as to whether or not specialised care for mother and child is indicated in cases of gestational antidepressant use.</p> <p>Conclusion</p> <p>Primary health care workers are not univocal concerning therapy for pregnant women with depression. Although more research is needed to account for all safety issues, local or national policies are indispensable in order to avoid undesirable practices, such as giving contradictory advice. GPs and pharmacists should address the subject during their regular pharmacotherapeutic consensus meetings, preferably in collaboration with the TIS or other professionals in the field.</p

Excess of serotonin affects neocortical pyramidal neuron migration

The serotonin transporter (SERT) is a key molecule involved in the homeostasis of extracellular levels of serotonin and is regulated developmentally. Genetic deletion of SERT in rodents increases extracellular levels of serotonin and affects cellular processes involved in neocortical circuit assembly such as barrel cortex wiring and cortical interneuron migration. Importantly, pharmacological blockade of SERT during brain development leads to phenotypes relevant to psychiatry in rodents and to an increased risk for autism spectrum disorders in humans. Furthermore, developmental adversity interacts with genetically-driven variations of serotonin function in humans and nonhuman primates to increase the risk for a variety of stress-related phenotypes. In this study, we investigate whether an excess of serotonin affects the migration of neocortical pyramidal neurons during development. Using in utero electroporation combined with time-lapse imaging to specifically monitor pyramidal neurons during late mouse embryogenesis, we show that an excess of serotonin reversibly affects the radial migration of pyramidal neurons. We further identify that the serotonin receptor 5-HT6 is expressed in pyramidal neuron progenitors and that 5-HT6 receptor activation replicates the effects of serotonin stimulation. Finally, we show that the positioning of superficial layer pyramidal neurons is altered in vivo in SERT knockout mice. Taken together, these results indicate that a developmental excess of serotonin decreases the migration speed of cortical pyramidal neurons, affecting a fundamental step in the assembly of neural circuits. These findings support the hypothesis that developmental dysregulation of serotonin homeostasis has detrimental effects on neocortical circuit formation and contributes to increased vulnerability to psychiatric disorders

Fluoxetine during Development Reverses the Effects of Prenatal Stress on Depressive-Like Behavior and Hippocampal Neurogenesis in Adolescence

Depression during pregnancy and the postpartum period is a growing health problem, which affects up to 20% of women. Currently, selective serotonin reuptake inhibitor (SSRIs) medications are commonly used for treatment of maternal depression. Unfortunately, there is very little research on the long-term effect of maternal depression and perinatal SSRI exposure on offspring development. Therefore, the aim of this study was to determine the role of exposure to fluoxetine during development on affective-like behaviors and hippocampal neurogenesis in adolescent offspring in a rodent model of maternal depression. To do this, gestationally stressed and non-stressed Sprague-Dawley rat dams were treated with either fluoxetine (5 mg/kg/day) or vehicle beginning on postnatal day 1 (P1). Adolescent male and female offspring were divided into 4 groups: 1) prenatal stress+fluoxetine exposure, 2) prenatal stress+vehicle, 3) fluoxetine exposure alone, and 4) vehicle alone. Adolescent offspring were assessed for anxiety-like behavior using the Open Field Test and depressive-like behavior using the Forced Swim Test. Brains were analyzed for endogenous markers of hippocampal neurogenesis via immunohistochemistry. Results demonstrate that maternal fluoxetine exposure reverses the reduction in immobility evident in prenatally stressed adolescent offspring. In addition, maternal fluoxetine exposure reverses the decrease in hippocampal cell proliferation and neurogenesis in maternally stressed adolescent offspring. This research provides important evidence on the long-term effect of fluoxetine exposure during development in a model of maternal adversity

Serotonin, genetic variability, behaviour, and psychiatric disorders - a review

Brain monoamines, and serotonin in particular, have repeatedly been shown to be linked to different psychiatric conditions such as depression, anxiety, antisocial behaviour, and dependence. Many studies have implicated genetic variability in the genes encoding monoamine oxidase A (MAOA) and the serotonin transporter (5HTT) in modulating susceptibility to these conditions. Paradoxically, the risk variants of these genes have been shown, in vitro, to increase levels of serotonin, although many of the conditions are associated with decreased levels of serotonin. Furthermore, in adult humans, and monkeys with orthologous genetic polymorphisms, there is no observable correlation between these functional genetic variants and the amount or activity of the corresponding proteins in the brain. These seemingly contradictory data might be explained if the association between serotonin and these behavioural and psychiatric conditions were mainly a consequence of events taking place during foetal and neonatal brain development. In this review we explore, based on recent research, the hypothesis that the dual role of serotonin as a neurotransmitter and a neurotrophic factor has a significant impact on behaviour and risk for neuropsychiatric disorders through altered development of limbic neurocircuitry involved in emotional processing, and development of the serotonergic neurons, during early brain development

Dietary intake of PFOS and PFOA in The Netherlands

VW

Opinions of Dutch stakeholders with regard to registration of products containing nanomaterials

Het is momenteel nog niet precies duidelijk in welke consumentenproducten nanomaterialen zitten: soms wordt onterecht geclaimd dat ze erin zitten, maar andersom kan ook het geval zijn. Het is echter van belang om te weten of producten nanomaterialen bevatten, omdat de veiligheid ervan nog moeilijk te beoordelen is. Om meer duidelijkheid over de aanwezigheid van nanomaterialen te krijgen, gaan in Europa stemmen op om consumentenproducten te registreren waar nanomaterialen in zitten. Momenteel is de Europese Commissie nog te sterk verdeeld om tot een registratiesysteem te komen. In Nederland heeft de Tweede Kamer in 2009 een motie aangenomen waarin de regering wordt verzocht om een registratiesysteem te helpen ontwikkelen dat vanuit Europa wordt geïnitieerd. Met het oog daarop heeft het RIVM geïnventariseerd hoe beleidsmedewerkers van enkele ministeries, brancheverenigingen van de industrie en enkele non-gouvernementele organisaties over een dergelijk registratiesysteem denken. De meningen hierover blijken verdeeld te zijn. Stakeholders hebben vooral vragen over de mate waarin de bestaande regelgeving toereikend is en over wat het beoogde doel is van een registratiesysteem. Als belangrijkste doelen van een registratiesysteem wensen zij: transparantie voor de consument, in de vorm van informatie op basis waarvan de consument bewust voor een product kan kiezen, en traceerbaarheid van het nanomateriaal in de productieketen. Punten van discussie zijn de wijze waarop dit bereikt moet worden en de vraag of een database daarvoor de beste vorm is. Een alternatief voor de transparantie is het etiketteren van producten. De industrie kan de traceerbaarheid ook zelf organiseren door op aanvraag snel informatie te leveren. Het is van belang dat er consensus is over het doel van het registratiesysteem voordat het wordt opgezet. Ook moet duidelijk zijn wie het registratiesysteem gaat gebruiken (doelgroep) en welke informatie zij in het systeem wensen te vinden. Daarna kan pas gesproken worden over de verdere vormgeving ervan en wie de verantwoordelijkheid ervoor moet dragen.At present, it is not clear which consumer products contain nanomaterials. It is sometimes claimed that certain products do contain such materials when they do not, and vice versa. It is important to identify all products which contain nanomaterials because our knowledge with regard to their safety remains incomplete. Various parties have called for a system of product registration to be introduced at the European level in order to provide greater clarity. The European Commission is, however, divided on the matter and has been unable to arrive at a firm decision thus far. In 2009, parliament adopted a motion calling for the Dutch government to assist in the development of a registration system to be implemented at the European level. The National Institute of Public Health and the Environment (RIVM) then approached the stakeholders - the relevant ministries, industry federations and non-governmental organizations - to gauge opinions regarding the desirability of a formal registration system and the form that any such system should take. Opinions proved to be divided. A particular point of concern among stakeholders is the usefulness of a separate registration system alongside existing legislation, which some see as adequate to achieve the same ends. It is assumed that the main purposes of a registration system would be to offer greater transparency for the consumer (in the form of information which permits a considered purchasing decision), and the ability to trace nanomaterials throughout the production chain. The main differences of opinion concern the manner in which these aims can best be achieved, and in particular whether a database is the most appropriate instrument with which to do so. Product labelling has been suggested as an alternative means of ensuring transparency, while traceability can be assured if the industry itself undertakes to provide timely information on request It is important to achieve consensus with regard to the purpose of a registration system before any further action is taken. It must be clear who is to use that system (the target group) and what information they require. Only when such aspects have been finalized will it be possible to proceed to the design phase, or to establish who is to bear overall responsibility.VW