Frequently Asked Questions
Polybrominated diphenyl ethers or PBDEs, are a group of chemicals that are used as flame retardants in a variety of polymer resins and plastics. They are found in many products in most homes and businesses, including furniture, TVs, stereos, computers, carpets, and curtains.
PBDEs are also used, to a lesser degree, in some textiles, adhesives, sealants and coatings.
PBDEs are ubiquitous, global environmental pollutants that are present in all parts of the environment, and can be found in samples taken virtually anywhere.
They are harmful to the environment, build up in living organisms, and last a long time in the environment.
The preliminary finding of the screening assessment is that PBDEs are toxic to the environment, as defined under the Canadian Environmental Protection Act, 1999.
PBDEs have been detected in all parts of the environment (air, water and land). While overall concentrations of PBDEs in the environment are low, current levels may threaten some wildlife and invertebrates. There is also some concern because of the rapid increases in the levels of PBDEs detected in the environment since the early 1990’s.
Recent studies using rodents provide evidence that exposure to PBDEs during critical growth periods may lead to behavioural disturbances, and liver effects. They can also interfere with the normal production of some thyroid hormones.
The scientific assessment found no evidence that current levels of PBDEs in the environment are harming human health at the moment. However, the rapid increase in PBDE levels in the environment over the last several years is cause for concern. Health effects have been observed in laboratory animals, but only at levels much greater than those to which people are exposed in Canada.
Studies in other countries have shown that it is possible to reverse the increase in PBDEs in the environment by reducing their use. Based on these studies, where breast milk levels of PBDEs declines after strict controls were put in place, Health Canada believes that measures to protect the environment from PBDEs are also likely to protect human health.
The presence of low levels of PBDEs in human breast milk and blood simply indicates that people are being exposed to these compounds, which are persistent in the environment. Such chemicals may also accumulate in fatty tissues and fluids such as human breast milk due to their physical-chemical properties. However, it does not automatically follow that PBDEs are causing harmful effects in humans. Human exposure in Canada is much lower than levels associated with effects in experimental animals, even based on the worst-case estimates of exposure in the screening health assessment.
No. They are not manufactured in Canada but are imported in finished articles, or are used in making a variety of commercial and consumer products such as computer housings, household appliances, furniture, automotive/aircraft seating and interiors, and a variety of electrical and electronic components.
A recent survey conducted by Environment Canada found that approximately 1,300 tonnes of PBDEs in commercial products were imported or shipped into Canada in 2000. PBDEs were also imported in a variety of finished consumer products. The volumes reported do not include quantities imported in finished articles. No PBDEs were manufactured in Canada in 2000.
Releases of PBDEs to the environment can occur during manufacturing and processing operations, throughout the service life of articles containing PBDEs, and when articles that contain PBDEs are disposed of.
Yes. The screening assessment conducted by Health Canada and Environment Canada looked at seven of the most common PBDEs. They are all similar in chemical structure, but each has a slightly different chemical composition. The seven PBDEs are: tetrabromodiphenyl ether; pentabromodiphenyl ether; hexabromodiphenyl ether; heptabromodiphenyl ether; octabromodiphenyl ether; nonabromodiphenyl ether; and decabromodiphenyl ether. In Canada, the chemicals are found in different combinations in three commercial products generally referred to as commercial penta–, octa–, and deca–brominated diphenyl ethers.
The commercial mixtures PentaBDE and OctaBDE are being banned by the European Union (in effect August 2004), California (2006), Hawaii (2008) and Maine (2006). Maine has also proposed a ban on DecaBDE for 2008.
The U.S. Environmental Protection Agency (U.S. EPA) has reached a voluntary agreement with the major manufacturer of PeBDE and OBDE to cease production by the end of 2004.
The findings of the screening assessment are generally consistent with assessments or regulatory decisions in other jurisdictions and the recommendations may actually go further in some respects.
In light of the assessment, Environment Canada is working with industry and other stakeholders to prepare a strategy to minimize the impact of PBDEs on the environment.
The substances that are likely of greatest concern are already being phased out of use in Canada. The commercial mixture Penta-BDE has been out of use in Canada for about a year. The commercial mixture Octa-BDE has seen limited use in Canada and steps are being taken to find alternatives.
The approach taken in a screening assessment is to examine various sources of existing information and develop conclusions based on a weight of evidence approach, considering the full range of the substances’ properties observed in the environment or what one would expect to find based on laboratory information and modeled data for these and related chemicals.
Relevant data from original literature, review documents, commercial and government databases and indices were all reviewed as part of the screening assessment. Environment Canada researchers retrieved references from a literature database search, made direct contacts with researchers, academics, industry and other government agencies to obtain relevant information. In addition, ongoing scans were conducted of open literature, conference proceedings and the Internet for relevant information about PBDEs.
The substance matter in the assessment has been subjected to peer review by Canadian and international experts selected from government and academia.
CEPA 1999 provides for screening assessments for some substances on the Domestic Substances List. PBDEs meet the criteria for a screening assessment, which can be faster and less costly than a Priority Substances List assessment.
Following a 60-day public comment period and analysis of the comments, a final decision will be made on whether they are toxic as defined in the Canadian Environmental Protection Act, 1999.
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