Banning Flame-Retardant Materials
Weighing Science and Precaution
January 2007
For the third year, environmental activists are promoting a ban on a certain flame-retardant compound known as polybrominated diphenyl ether (PBDE). Having failed to pass a bill to outlaw PBDEs in the last two legislative sessions in Olympia, environmental activists have made changes to last year's bill in an effort to make it more palatable to the legislature. The authors of the legislation watered down the trigger for the ban, requiring a new state panel to confirm that there are other fire-retardant materials that act as "an effective flame retardant that is safer than commercial deca-BDE and technically feasible." Two years after that confirmation, the ban would take effect. Washington State would be the first to take this dramatic step.
While this is a concession from the previous bill, supporters of the current bill still refer to it as a "ban" on PBDEs. Indeed, the practical outcome would likely be a total ban, because manufacturers and others would immediately begin moving away from PBDEs due to uncertainty about their future. In addition, no company is likely to risk its ability to comply with fire-safety standards based on speculation about what a government panel may decide.
While there are a range of issues for and against the ban, the arguments to ban PBDEs come down to three: 1) the potential harm of PBDEs, 2) the availability of alternatives and, 3) a desire to be "precautionary" even if the science is unclear. In each of these areas, the arguments of those who want to ban PBDEs are at best overstated or, at worst, simply factually incorrect.
First, in the interest of clarity, I am focusing my discussion on key issues. There is a fair amount of hyperbole involved in this issue and questioning of the motives of the various sides. One legislator claimed before a legislative committee that the only issue is "how cheaply" we can produce flame-retardants, implying that money is the only motive. Arguments such as these are rarely productive, and I won’t question the motives of the proponents or opponents.
Second, scientific issues can devolve into a battle of the studies. Again, for the sake of clarity, I will use only the data provided by the state Department of Ecology (DOE), the Washington Department of Health (DOH) and the Washington Toxics Coalition. By using only the data from proponents of a ban, I hope to avoid problems related to the questioning of data that frequently leave decisionmakers unsatisfied and without clear guidance.
As a personal aside, I have no small interest in this issue. One of the primary uses of PBDEs is as a flame-retardant in computer housings. As a former computer programmer, I have had more exposure to computers and, by extension, the dust from computer housings that carry PBDEs, than most people. If PBDEs are truly toxic to humans, I am a potential poster child for a ban. Each of us, however, has to make a sound judgment about the risks we face daily in life and need to sort out fear from fact. In the case of PBDEs, there is far too much of the former and not enough emphasis on the latter.
PBDEs are perhaps the most common fire retardant used in a range of common products, including aircraft, computers and some furniture. In each of these categories, there are alternative retardants, but each has problems. Some are more toxic than PBDEs, as I will illustrate later.
Also, there is more than one type of PBDE – each named according to the number of bromine atoms in each compound. Older versions are known as tetra-BDE (with four bromines), penta-BDE (with five bromines) and octa-BDE (with eight). None of these older forms of PBDE is currently manufactured. The only version currently produced is deca-BDE, with 10 bromines.
It is important to keep these distinctions in mind because many of the arguments about banning PBDEs conflate all types of the compound, despite some very different data about their impacts on people and the environment.
The primary argument in favor of banning PBDEs has been that they are “persistent bioaccumulative toxins,” meaning that they build up in the body over time. This is important because as toxins accumulate, they may reach levels where they have negative health impacts. A range of potential impacts are claimed, but this year the emphasis is on impacts to orca whales and children.
Much of the potential impact, however, is based on penta-BDE and octa-BDE, rather than on the deca-BDE that the legislation would actually ban. The reason for basing potential impacts on penta-BDE and octa-BDE is that proponents of the ban argue that when exposed to sunlight, deca-BDE, “while relatively safe in its original form, breaks down into more toxic forms of PBDEs.”[1] Over time, they say, deca-BDE loses some of its bromines, leaving more toxic compounds.
This is an important element of the argument for a ban because there is fairly wide agreement that deca-BDE is not, in and of itself, toxic. For example the DOE and DOH note that “Ecology and DOH agree that Deca-BDE is not a PBT in terms of meeting the ‘P’, ‘B’, and ‘T’ criteria as specified in Section 320 (2) of the recently adopted PBT Rule (Chapter 173-333 WAC), and as such, based on Deca-BDE’s chemical properties, is not a persistent bioaccumulative toxin (PBT).”[2]
Put simply, deca-BDE is neither “persistent,” nor “bioaccumulative,” nor “toxic.” The agencies go on to argue, however, that due to the toxicity of the other forms of PBDE, deca-BDE does meet the definition.
The amount of degradation is a subject of debate. The DOE/DOH report notes that because there are a range of types of PBDE already in the environment, “products provide a unique challenge to the collection of meaningful field data related to deca-BDE degradation.”[3] There are studies that have examined degradation in the lab that provide some indication.
The Washington Toxics Coalition argues in its “Pollution in People” report that “A study of the degradation of deca in house dust found rapid breakdown and concluded that 83 percent of the deca converted to other PBDEs...”[4]
This is simply wrong and misquotes the study the coalition cites.
The study cited actually reports that only about 25 percent of the deca-BDE may break down into other PBDEs. A December 2005 DOE and DOH report[5] cites the same study, saying “Over the 90 hour sunlight exposure, the concentration of BDE-209 in the house dust decreased by almost 30 percent. This decrease coincided with an increase in the concentration of nona-, octa-, and heptabrominated congeners. A mass balance calculation suggests that 83% of the BDE-209 loss was due to debromination into less brominated congeners.”[6] About 30 percent of deca-BDE in this study became other compounds. Of that 30 percent loss, 83 percent appears to become other PBDEs, for a total of 25 percent. By skipping the first step, ban proponents’ math is off by 350 percent.
The other question is, to what types of PBDE does deca-BDE break down? If it breaks down to penta-BDE, then the potential lifetime toxicity increases, as opposed to breaking down to less toxic nona-BDE (with nine bromines). On this, the science is also fairly clear. The DOE/DOH response to public comments on the PBDE plan cites one study where deca-BDE broke down into nona-BDE and octa-BDE.
Another presentation available on the Department of Ecology website notes that while a range of PBDEs were found, “the degradation rate decreased with each debromination,”[7] meaning most of the deca-BDE turned into safer nona- and octa-BDEs rather than the more toxic penta-BDE.
This is an important result, because many of the claims of impact and the data showing an increase in PBDEs rely on high levels of penta-BDE and tetra-BDE.
The “Pollution in People” report cites the levels of PBDE in Dr. Patricia Dawson as a reason to ban deca-BDE. In that study, however, the total levels of PBDEs in Dr. Dawson are almost entirely related to tetra- and penta- BDE, listed in the study as Br4-DPE-47 and Br5-DPE-99.[8] Ironically, Dr. Dawson has the lowest level of deca-BDE (Br10-DPE-209) of any of the people studied in the “Pollution in People” report. In other words, banning deca-BDE would do very little to reduce the level of toxics in people like Dr. Dawson.
Looking more closely at the data included in the “Pollution in People” report shows no correlation between the amount of deca-BDE in someone’s body and the amount of other forms of PBDE. Using data from the “Pollution in People” appendix, the graph below shows the amount of deca-BDE and octa-BDE found in each of the 10 people studied in the report.[9] As is evident, the person with the highest level of deca-BDE also has the lowest level of octa-BDE.
Likewise, the person with the lowest level of deca-BDE has the highest level of octa-BDE. In between, virtually every other ratio is found, with levels rising and falling inconsistently. In five cases, the levels of octa- and deca-BDE rise or fall together and, in five cases, the levels of octa- and deca-BDE.png)
move in opposite directions from the previous person. If there was a consistent ratio, similar trends would be the expectation. When looking at deca-BDE and other types of PBDE, the absence of a trend is also evident.
These results call into question the fundamental argument for outlawing PBDEs and highlight two problems. First, the amount of deca-BDE that degrades into other forms is relatively low, with approximately one-quarter of deca-BDE degrading into other forms of PBDE. Second, of that amount, most of it remains in the nona- and octa- form, which are less toxic forms than penta-BDE. Given that the DOE/DOH note that the only reason to ban deca-BDE is due to the threat from degradation, the underlying rationale for the ban is questionable.
One word that consistently arises among advocates of a PBDE ban is “precaution.” The argument is based on what is known as the “Precautionary Principle.” The Washington Toxics Coalition devotes a special section of its website to the issue noting that “The Washington Toxics Coalition embraces the Precautionary Principle as the basis of our approach to human and environmental health.”[10] The argument, in its most basic form, is that when there are unknowns, it is better to be cautious and ban or restrict anything that might be potentially damaging. Asbestos is the most frequently used example of when this type of principle should have been followed.
This approach, however, is plagued with problems. First, there is no reason that precaution should favor one side or the other. Which is more important, the danger of fire or the danger of PBDEs? Why should one type of hazard automatically be given presumption? All negative impacts on people or the environment should be carefully weighed, no matter what the source.
While asbestos is the anecdote of choice for advocates of the principle, they have recently stopped talking about DDT. In the case of DDT, the total banning of the most effective pesticide in use against malaria-carrying mosquitoes contributed to the death of hundreds of thousands, if not millions, of people in Africa. In fact, the World Health Organization (WHO) recently announced the limited reintroduction of DDT as a tool saying, “We must take a position based on the science and the data. One of the best tools we have against malaria is indoor residual house spraying. Of the dozen insecticides WHO has approved as safe for house spraying, the most effective is DDT.”[11]
Following the Precautionary Principle, advocates must either argue that the DDT ban was justified (given the uncertainty about the science at the time) or that the ban was contrary to science. They must also explain how following the principle in the future won’t create similar negative side effects that are harmful to humans.
Further, the Precautionary Principle moves decisions from the realm of scientific analysis to the world of political gamesmanship. When following the principle, uncertainty always accrues to the benefit of environmental activists. As a result, these activists, rather than engaging in discussion that promotes scientific understanding and clarity, instead seek to stall and create uncertainty. Their goal is simply to make weighing the pros and cons of various proposals as difficult as possible. It is understandable that some environmental activists would seek to promote this counterproductive standard as a means to an end. Decisionmakers, on the other hand, should not accept a standard that makes confusion a primary strategy.
Along these lines, there is discussion of creating an objective fire safety standard that could be used by the panel to examine alternatives to deca-BDE. I am not an expert on fire safety, but the notion of objective standards replacing subjective judgments seems positive.
The final key argument used by proponents of a ban on deca-BDE is that alternatives to PBDEs exist that are just as effective, but less toxic. The Washington Toxics Coalition argues, “Numerous companies, including Sony, HP, and Dell, have stopped using deca in favor of safer fire retardant alternatives and their products continue to meet the highest safety standards for televisions and computers.”[12] In reality, however, some of the chemicals that are being used to replace PBDEs are more toxic, according to DOE.
Dell’s website notes that they are phasing out PBDEs and using other compounds, noting that “Printed circuit boards typically contain brominated flame-retardants such as Tetrabromobisphenol A (TBBA).”[13] TBBA is listed by DOE as a potential alternative. DOE’s assessment of its toxicity, however, shows it is more toxic than PBDEs.[14]
Another potential alternative is known as RDP. The DOE report notes that RDP rates as medium-to-high (“M-H”) toxicity, and that there is a low level of information on its toxicity. It also notes there is no information on whether it persists or bioaccumulates.[15] In other words, there is a very low level of information about the “P,” the “B” or the “T” in persistent bioaccumulative toxins. This means that the level of potential risk to humans is very high because there are so many unknowns.
Interestingly, while proponents of the ban claim there are known alternatives, DOE states it knows of no acceptable alternatives. In testimony before the legislature, DOE officials said that the State of Maine may have one option, but they had not examined it.[16]
The proposal before the legislature anticipates this issue by requiring a panel to certify that safer alternatives exist. No PBDE ban would occur, proponents argue, until certification of alternatives was achieved. This is, however, an ephemeral promise. No business is going to risk its future on the potential decision of a government panel that has already publicly stated its desired outcome. Business leaders are likely to believe that there is a bias against PBDEs. They are right.
In fact, in the absence of an outright ban, the purpose of the bill can be said to be the creation of a statutory bias against PBDEs. That is one reason that environmental activists refer to the bill not as an “examination of alternatives to PBDEs,” but as the “elimination of all PBDEs.”[17]
A closer look at the justification for banning PBDEs shows that the key reasons for advocating a ban are overstated and, without skewing policy judgments by using the Precautionary Principle, the case for a ban is poor. As noted above, data about the relationship between deca-BDE and more toxic forms is thin. A hasty, ill-considered ban is not only unnecessary, it would actually push manufacturers toward compounds that are more toxic and more risky.
Policymakers do have an important responsibility to monitor the spread of potentially toxic chemicals in the environment. The existing PCB ban is often cited by advocates who want to ban PBDEs, and with good reason. PCBs are truly toxic and continue to have a negative environmental impact. Proponents are certainly right to say we should not wait to see negative impacts before we act to head off future problems. In the case of “persistent” toxins, waiting until that time would mean that the health threat would continue for years while the compounds broke down naturally.
Caution, however, must be founded on an unvarnished assessment and honest science. Biased discussion and overstated science lead to poor decisions. The recent case of the DDT ban is a dramatic example of the potential human costs of such biases. It is an example that policymakers should take to heart before banning PBDEs.
[1] Washington State Department of Ecology and Washington State Department of Health, “Responses to Public Comments on the Draft and Draft Final Washington State Polybrominated Diphenyl Ether (PBDE) Chemical Action Plan,” May 4, 2006, http://www.ecy.wa.gov/pubs/0607014.pdf (accessed January 15, 2007) p. 9.
[2] Ibid., p. 14.
[3] Ibid., p. 12.
[4] Toxic-Free Legacy Coalition, “Pollution in People: A study of toxic chemicals in Washingtonians,” May 2006, www.pollutionpeople.org (accessed June 23, 2006), p. 59.
[5] Washington State Department of Ecology and Washington State Department of Health, “Washington State Polybrominated Diphenyl Ether (PBDE) Chemical Action Plan: Draft Final Plan,” December 1, 2005, http://www.ecy.wa.gov/biblio/0507048.html (accessed January 1, 2006).
[6] Ibid., p. 35.
[7] Alex Stone, “Degradation of deca-BDE: Recent Scientific Work Since Interim CAP,” http://www.ecy.wa.gov/programs/eap/pbt/pbde/docs/oct25/Degradation_of_deca.pdf (accessed January 15, 2007).
[8] Toxic Free Legacy Coalition, p. 59.
[9] Ibid.
[10] Washington Toxics Coalition, “General Information – Washington Toxics Coalition,” http://www.watoxics.org/issues/precautionary-principle (accessed January 16, 2007).
[11] World Health Organization, “WHO gives indoor use of DDT a clean bill of health for controlling malaria,” September 15, 2006, http://www.who.int/mediacentre/news/releases/2006/pr50/en/index.html (accessed December 20, 2006).
[12] Washington Toxics Coalition, “Protecting Kids’ Health by Eliminating Toxic Flame Retardants (PBDEs),”
[13] Dell Computer, “Dell and the Environment,” http://www.dell.com/content/topics/global.aspx/corp/environment/en/faqs?c=us&l=en&s=corp&~tab=3 (accessed May 31, 2006).
[14] Department of Ecology et al., December 1, 2005, p. 71.
[15] Ibid.
[16] Ted Sturdevant, Washington State Department of Health, Testimony before the Health Select Committee on Environmental Health, January 9, 2007. http://www.tvw.org/MediaPlayer/Archived/WME.cfm?EVNum=2007011009&TYPE=A (accessed January 15, 2007).
[17] Priorities for a Healthy Washington, “Priorities for a Healthy Washington – Eliminating Toxic Flame Retardants,” http://www.environmentalpriorities.org/toxicsban (accessed January 16, 2007).