READ HABITABLE’S NEW REPORTDesigning Out Plastics: A Blueprint for Healthier Building Materials
HealthIgniting the Debate on Flame Retardants
People
Arlene Blum is a biophysical chemist, author and mountaineer.
She is the founder and executive director of the Green Science Policy Institute which works with scientists, government, industry, and non-profits to facilitate more informed decision-making about flame retardants and other chemicals used in consumer and building products.
Healthy Building Network founder Director Bill Walsh caught up with Elaine, recording the following conversation:
Bill Walsh:
How did you get started working on flame retardants?
Arlene Blum:
Thirty years ago, as a researcher at the University of California, Berkeley, I published a paper in Science magazine showing that “Tris” flame retardants in children’s sleepwear caused mutations, were possible cancer hazards, and migrated from pajamas into children. The flame retardants were removed from children’s sleepwear in 1977, but chlorinated tris is now back in use in foam in furniture and other products.
BW:
Why are you so concerned about flame retardants in building materials?
AB:
If a building contains halogenated flame retardants in the insulation, they can filter into the building throughout its life and also form toxic dioxins if the building burns.
I know it’s a real dilemma for people when they learn that plastic insulation materials, such as polystyrene, polyisocyanurate, and polyurethane, that can help reduce climate change, often contain flame retardants which can cause serious health and environmental harm. But the good news is that this is a problem that can be solved.
Once green building professionals understand the issue, they can move to safer substitutes and strategies that don’t have potential adverse health impacts. In fact of the various groups with which I’ve worked on reducing toxics in products, the green building community has been the most responsive. So I am very happy to have the opportunity to share the message about moving away from the use of halogenated flame retardants at Greenbuild.
The new LEED Pilot Credit on Chemical Avoidance for not using phthalates and halogenated flame retardants inside buildings should accelerate our progress towards healthier buildings.
BW:
You mentioned that this is also a chemical contamination problem that could have negative impacts on our health and well-being at a global level? How?
AB:
Many halogenated flame retardant chemicals are persistent and bioaccumulate especially in humans and animals high on the food chain. It is almost impossible to clean them up once they are out in the world. For example, PCBs, chlorinated chemicals that were also used as flame retardants, were banned in 1977, but very high concentrations can still be found in wildlife and some human populations today. Studies show that human breast milk contains flame retardants, and toddlers have three to four times higher body levels than their mothers.
When tested in animals, many halogenated flame retardants have been found to cause health problems like cancer, reduced fertility and IQ, thyroid disorders, and developmental impairment. Many halogenated flame retardants are also endocrine disrupting chemicals that can harm us at very low concentrations.
BW:
How do you weigh the known benefits today against long term unproven risks?
AB:
In furniture there is no proven benefit. It makes more sense to reduce the sources of ignition with fire-safe cigarettes and candles than to put potentially toxic chemicals in all the possibly flammable materials in our homes. Today the risk of home fires is diminishing due to a 50% decrease in cigarette consumption since 1980, enforcement of improved building, fire, and electrical codes, increased use of sprinklers and smoke detectors. These strategies provide measurable improvements in fire safety without toxicity.
Smoke and toxic gases kill people in fires, more than flames. Research on furniture fires show that while halogenated flame retardants can reduce the time for ignition by seconds, they greatly increase the carbon monoxide, smoke, and soot. The chemicals also release dioxin and related compounds when burned at relatively low temperatures. So the benefits of retarding the fire with toxic chemicals is greatly reduced by the increased fire toxicity and dioxins at the fire scene.
Given the lack of proven benefit in some cases, the risk-benefit calculation on chemical flame retardants can be tenuous even before you start to consider the widespread exposure to these chemicals on a daily basis.
Better methods of reducing fire risks include careful material selection and alternative fire suppression strategies that can be designed into products and buildings.
BW:
How can people take this knowledge and translate it into action?
AB:
When people know about the hazards of the flame retardants that are commonly used in many plastic foam insulations, furnishings and other building materials, they can choose alternative products or push for less toxic flame retardants. When green building professionals make these choices, this will increase the availability and decrease the cost of the alternatives.
Moving the market demand for flame retardants in the huge building sector can also help with policy changes. We have been providing scientific support to change a California furniture flammability standard to provide similar or greater fire safety without flame retardant chemicals.
We also need national chemical policy reform. Because of weaknesses in the Toxic Substances Control Act, which has not been updated since 1976, chemicals are innocent until proven guilty and that proof is almost impossible to obtain. Even asbestos could not be banned. And manufacturers are not required to perform any toxicity tests before putting chemicals into products! Green buildings need to be both energy-efficient and healthy. Reducing the use of halogenated flame retardants will help achieve this and help create a healthier world for us all.
HealthDid You Know…
Resource
…that some building products may expose you to the chemical banned from plastic bottles?
Everyone has heard the news about the health concerns associated with bisphenol A (BPA) leaching from baby bottles, food can liners and perhaps most famously those distinctive polycarbonate plastic water bottles popularized by Nalgene.[1] Last May, Chicago became the first city in the U.S. to ban the sale of baby bottles and sippy cups made from BPA. Few, however, are aware that BPA is a chemical component of epoxy resins used in a wide range of building materials, typically paints, sealants, adhesives and fillers,[2] that may put manufacturing workers, installers, and building occupants at risk.
Epoxy resins are used in building materials, often listed on a material safety data sheet as a proprietary mixture, without disclosure that the resin is made from BPA. While manufacturers claim that the BPA in epoxy resins is consumed entirely in the production process and does not show up in the final products, scientists investigating the metabolic breakdown of epoxy resins during occupational exposure have found that epoxy resin products can be metabolized in the human body back into BPA and may impact the endocrine and reproductive system of those exposed.[3]Animal studies have linked this hormone-disrupting chemical to prostate cancer, breast cancer, pre-diabetes (insulin resistance), abnormal fat metabolism, early puberty, and changes in the way the brain develops resulting in behavioral abnormalities.[4]
The BPA expert panel from the Center for Evaluation of Human Risks to Reproduction raised concern about BPA in epoxy-based resins, reporting to the National Toxicology Program that, “several studies collectively suggest hormonal effects of bisphenol A exposure, including one in occupationally exposed male workers likely exposed through multiple routes including inhalation…”[5] The NTP’s final monograph states that “a number of studies, when considered together, suggest a possible effect on reproductive hormones, especially in men exposed to higher levels of bisphenol A in the workplace.”[6] Germany has already instituted occupational exposure limits for bisphenol A.[7]
Recent biomonitoring studies have raised concerns about widespread human exposure to BPA. A National Health and Nutrition Examination Survey (NHANES) study found that more than 90% of people in a representative sample of the general population have BPA residues in their urine[8] and that there must be significant non-food exposures to reach such levels.[9]
It is likely that BPA in building products will become subject to greater health and safety regulation, but responsible specifiers do not need to wait for the regulatory system to catch up with the science to protect their clients. Products are available that can replace epoxy-based coatings and adhesives. For example, many paint companies now offer high-performance low-VOC water-based acrylic paints and acrylic-based adhesives for flooring, carpets, and wall covering. For applications where high-performance BPA-free substitutes are not yet available, the act of asking manufacturer reps for products without bisphenol A is an important step to prod the industry to bring safer high performance alternatives to market.
For a comprehensive discussion of the emerging science on BPA risks, read “Bisphenol A in Building Materials: High Performance Paint Coatings.”
SOURCES
- BPA is also known as a component of dental sealants, some medical and dental devices, and thermal paper receipts.
- Epoxy-based products are used in a wide range of applications including coatings (such as paints, floor sealers and protective coatings), adhesives and fillers (including caulks, grouts, mortars, and putties), fiberglass binders and cement additives. Epoxy resins are also in some wind energy applications, generators and other electronic equipment, industrial tooling applications, and materials used in the art, aerospace and marine industries.
- Hanaoka T, Kawamura N, Hara K, Tsugane S. Urinary bisphenol A and plasma hormone solvents in male workers exposed to bisphenol A diglycidyl ether and mixed organic solvents. Occupational and Environmental Medicine, 2002; 59:626; Cha B, Koh S, Park J, et. al. Influence of Occupational Exposure to Bisphenol A on the Sex Hormones of Male Epoxy Resin Painters. Mol Cell Toxicol. 2008; 4(3): 230-234.
- Sarah Janssen, staff scientist for the NRDC, summarizes health concerns and the issue with links to some of the key science on her 7/13/09 blog entry “California is the latest battleground on BPA regulation”. http://switchboard.nrdc.org/blogs/sjanssen/many_of_my_blog_posts.html.
- Expert Panel cited in NTP-CERHR Monograph on the Potential Human Reproductive and Developmental Effects of Bisphenol A page 15. http://cerhr.niehs.nih.gov/chemicals/bisphenol/bisphenol.pdf.
- Ibid at page 37.
- Murakami T, Oyama T, Isse T, et al. International comparison of criteria for evaluating sensitization of PRTR-designated chemical substances. Environmental Health and Preventive Medicine 2007;12:56–65, citing Deutsche Forschungsgemeinshaft. List of MAK and BAT Values 2004, Commission for the investigation of health hazards of chemical compounds in the work area, Report No. 40. Weinheim: Wiley-VCH Verlag GmbH & Co. KGaA; 2004.
- Calafat A., et. al., Urinary concentrations of bisphenol A and 4-nonylphenol in a human reference population. Environ. Health Persp. 2005; 113(4): 391-395. http://www.ehponline.org/members/2004/7534/7534.html. Accessed online June 20, 2009.
- Stahlhut R, Welshons W, Swann S. Bisphenol A data in NHANES suggest longer than expected half-Life, substantial nonfood exposure, or both. Environ Health Perspect. (2009); 117(5):784-789. http://www.ehponline.org/docs/2009/0800376/abstract.html. Accessed online July 20, 2009.