HUMAN HEALTH RESEARCH Are the findings of flame retardants in fish, butter and other food items of concern for human health? No. Although several studies have detected very low levels of certain PBDEs in fish, meats, dairy products and other food items, public health experts have confirmed that even the highest levels detected are a factor millions of times below the acceptable limit from a toxicological point of view. As a matter of example, a 150-pound (+/- 68 kg ) individual could consume over 160.000 pounds of cheese – the weight of a fully-loaded Boeing 727 – every day and still be at a level of exposure considered of no risk by, for example, the US National Academy of Sciences. In particular, examining the recent findings of PBDEs in salmon, experts agree that the extremely low levels found pose no significant risk and the benefits of eating salmon outweigh any potential risks which may be present. In the meantime, the industry has initiated in Europe a specific programme with user industries of Deca-BDE in conjunction with EU regulators aimed at establishing best practice in industrial emissions controls for the use of Deca-BDE. This programme will contribute in further controlling and reducing emissions to the environment. It is planned to develop similar voluntary programmes for other commercial brominated flame retardants. Further information: - BSEF
press release “Salmon study findings already addressed
by industry voluntary measures”, 10 August 2004 What do the levels found in blood represent in terms of a risk to human health? Findings of any man made chemical in human blood do not themselves equate automatically with a health risk. Prof. Dr. Martin van den Berg, from the University of Utrecht’s Institute of Risk Assessment Sciences, has said that “occurrence of a given chemical in the human body is not synonymous with a risk or effect, but depends on the concentration”. Two independent peer reviews studying the presence of the flame retardant Deca-BDE in blood, conducted respectively by the Institute of Occupational Medicine (IOM) and by van den Berg have shown that recently reported findings of this chemical in blood do not pose a health risk. The levels of Deca-BDE reported in recent biomonitoring reports, are well below any possible concern for human health. Furthermore, these results were fully integrated in an evaluation of the substance by the EU Scientific Risk Assessment authorities. This body concluded the risk assessment of Deca-BDE on 26 May 2004 and decided that no restrictions were needed on the use of Deca-BDE due to a lack of identified risks. The biomonitoring reports contain data for a few brominated flame retardants which will similarly be addressed in their ongoing EU risk assessments. This said, a voluntary programme has been initiated with user industries of Deca-BDE, in conjunction with EU regulators, aimed at establishing best practice in industrial emissions control for the use of Deca-BDE. This programme will contribute to further controlling and reducing emissions of Deca-BDE to the environment for the whole of Europe over the next years. It is planned to develop similar voluntary programmes for other brominated flame retardants in Europe as well as in the US (HBCD, TBBPA). References: - IOM
review biomonitoring results What PBDEs have been found in breast milk? All published data on "PBDEs" in breast milk refer to one commercial product only: PentaBDE, which is being phased out in the European Union. There are recent concerns that Deca-BDE may be found in breast milk. Although there have been no recorded findings, the US EPA's Voluntary Children’s Chemical Evaluation Programme (VCCEP) has looked into the possible effects of Deca-BDE assuming it would be found in breast milk. The data submitted to VCCEP looked at exposure scenarios including Deca-BDE being ingested by infants through breast milk; however it concludes that "there is no biological threat, even at extreme high-end dose estimates, {…} that there is no potential risk to the general population". For the Voluntary Children’s Chemical Evaluation submitted to EPA see: http://www.bsef-site.com/newsmanager/uploads/vccep.pdf Are the levels going up, down or staying the same in various regions around the world? The PBDEs detected in breast milk are similar to those detected in wild-caught fish. About 50-70% of the total amount is commonly made up of one specific molecule: 2,2’,4,4’-TetraBDE. The next most common is 2,2’,4,4’,5-PentaBDE. These specific molecules are major components of one PBDE product: “PentaBDE”. It’s been reported that total PBDE levels in breast milk
collected in Sweden increased during the 1990s’, and peaked
in 1997; they are declining since a couple of years due to the declining
use of PentaBDE in Europe (and consequently lower emissions). How did these compounds get in breast milk? At this point, we can’t answer this question with any degree of certainty. There simply hasn’t been enough research to positively identify how a woman was exposed. For other environmental compounds, the diet is typically the major source. Recent work measuring levels in a typical “market basket” tends to indicate this is also true with regard to “PBDEs”, but at this point it’s too early to state this definitively. Do the levels in breast milk pose a risk to babies? Our best information indicates that levels in breast milk are hundreds or thousands of times below that which might cause a harmful effect. Leading authorities in the field continue to recommend breast milk as the best source of nutrition for babies. There’s a lot of speculation in the news about the kind of health or environmental effects that could be caused by BFRs. What effects have actually been found in humans or in animals in the environment? It’s easy to raise questions in the media and speculate on what might happen. Those raising questions aren’t required to have any particular expertise or to have demonstrated knowledge about the existing database. To date, no human health or environmental effects have been associated with the BFRs detected. Do BFRs accumulate in tissues? There seems to be a common misperception that BFRs, as a group, accumulate in animal and human tissues. However, studies have shown that this is not the case. Neither DBDPO nor TBBPA, which make up 50% of all BFRs sold, accumulate. Do BFRs affect the endocrine system of humans or animals? The endocrine system has become an active area of toxicology research in recent years. It’s composed of several organs: pituitary, thyroid, parathyroid, pancreas, adrenals, ovaries and testicles, all of which produce hormones that act on other parts of the body to integrate their various functions. No BFR has been shown to affect the endocrine system of humans. Changes in thyroid hormone blood levels in response to the PentaBDE product, HBCD and TBBPA have been shown in the rat. However, there was no associated harmful effect in the whole animal, and the mechanism by which the thyroid hormone level was lowered is not believed applicable to humans. Are BFRs toxic to the nervous system? Exposure to large, repeated doses of DBDPO, TBBPA, or HBCD over either the entire or a substantial portion of the animals’ lifetime has had no effect on their nervous systems. Similarly, no effect on the fetal nervous system was seen when the pregnant females were treated. One group of researchers has reported that 2,2’,4,4’-TetraBDE, 2,2’,4,4’,5-PentaBDE and DBDPO can cause behavioral or learning effects when given to 10 or 3 day old mice. Neither mice nor the study design are those typically used to study neurotoxicity. Further, the reported effects could not be reproduced in the rat. Can brominated flame retardants be released from consumer products? This is a very important aspect of assessing a potential health risk from brominated flame retardants for consumers. BFRs are used in everyday’s products such as computers, TVs, furniture etc. Theoretically, there is a possibility for exposure of consumers to the respective BFRs used in these products. BSEF has carried out detailed study programs together with respected experts in order to measure potential consumer exposure. All studies confirmed that consumer exposure from BFRs is negligible. Based on latest research undertaken by the German Federal Environment Agency (UBA) on the potential emissions of flame retardants from a wide variety of consumer products, no emissions could be detected from any of the three main BFRs (TBBPA, HBCD and Deca-BDE). The TBBPA findings of the UBA study were confirmed by a recent study by Herrmann et al. (Thomas Herrmann, Michael Ball, Klaus Rothenbacher, Martin Wesselmann, Organohalogen Compounds 61 (2003)259 “Emissions of Tetrabromobisphenol A from Computer Monitors”). The study investigated emissions from computer monitors which used additive TBBPA as a flame retardant in a test chamber and also in a real office experiment. Both scenarios found only negligible emissions of TBBPA. In a reference experiments, a monitor that did not contain TBBPA in the casing, but used TBBPA containing printed wiring boards was studied. No emissions of TBBPA from the printed wiring boards were found. Are BFRs endocrine disrupters? Scientists generally agree that certain endocrine active compounds may result in adverse effects in animal studies, although observed effects are typically related to high-dose exposure. The common conclusion is that it is unlikely that humans would be exposed to levels high enough to induce harmful effects. This would certainly be the case for BFRs. The EU Scientific Committee on Toxicity, Ecotoxicity and the Environment (CSTEE) states that: “It is important to realise that endocrine disruption is not a toxicological endpoint per se as is cancer or allergy, but that it is a descriptor for a functional change that may lead to adverse health effects. Rather, endocrine disruption should be seen in the context of well-established endpoints, primarily reproductive toxicity and impaired development.” At this point of time, there are no established test methods available for "endocrine disruption". These protocols are currently under development by the OECD. In the framework of the European Commission 5th Framework programme for research, technological development and demonstration activities, the flame retardant industry is co-sponsoring the largest risk evaluation initiative on “risk assessment of brominated flame retardants as suspected endocrine disrupters for human and wildlife health”, the so-called FIRE initiative. The overall objective of this multi- and interdisciplinary project is to improve risk assessment of certain brominated flame retardants (BFRs) for human health and wildlife. By integrating information on exposure, fate and toxicity, this project aims to contribute towards integrated risk assessments for humans and aquatic environment with respect to the potential for certain BFRs to act as endocrine disrupters. For more information on this project, please check the FIRE programme website at: http://www.rivm.nl/fire/ Are BFRs bio-accumulative? Most BFRs are not bioaccumulative or in other words they do not stay or build up in human bodies. Due to their high molecular weight and their low water solubility, they are not normally taken up by organisms. Only few of the many commercial BFRs are bioaccumulative like HBCD. One of the main BFRs on the market called Deca-BDE and used in E&E equipment was proven not bio-accumulative according to the World Health Organisation and the EU Risk Assessment.
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