Halogenated Flame Retardant Chemicals are an Unneeded Hazard
Halogenated flame retardants are chemical compounds containing chlorine or bromine bonded to carbon. They are used in commercial and consumer products to meet flammability requirements. However, in many cases, the manner in which flame retardants are used does not meaningfully improve fire safety.
In the case of foam plastic building insulation used below grade, for example, flame retardant chemicals do not provide a meaningful fire safety benefit.
Many halogenated flame retardant chemicals are persistent, bio-accumulative, and/or toxic. HBCD, a flame retardant chemical widely used in extruded polystyrene (XPS) and expanded polystyrene (EPS), has been banned under the Stockholm Convention in the Annex A list on Persistent Organic Pollutants.
Flame retardant chemicals are used in a wide variety of applications, including (in order, by volume in the U. S.):
- Building insulations
- Polyurethane foam
- Wire and cable
Health and Ecological Concerns
Halogenated flame retardants have been associated with reproductive, thyroid, endocrine, developmental and neurological disorders including decreased fertility, birth defects, learning disorders, and hyperactivity in animal studies. They are ubiquitous in wildlife and the environment and in almost all of the US population. New health studies associate these chemicals with decreased IQ, reduced fertility, and hormonal disruption in humans. Three different halogenated flame retardants are used in foam plastic building insulation in the U.S.: HBCD, PolyFR, and TCPP.
HBCD (hexabromocyclododecane) is typically used in polystyrenes at levels of up to 1% in expanded polystyrene (EPS) and up to 5% in extruded polystyrene (XPS). Concerns about HBCD include possible human health effects, aquatic toxicity, and bioaccumulation. In animal studies, it disrupts the hormone system and adversely affects the developing nervous system. As of November 2014, it is banned under the Stockholm Convention on Persistent Organic Pollutants.
“PolyFR” (brominated styrene butadiene copolymer) is a halogenated flame retardant used increasingly as a replacement for HBCD in polystyrene insulation. It is persistent, and health and ecological impacts from possible impurities and environmental breakdown products have not been studied. It poses similar lifecycle pollution issues.
TCPP (Tris(1-chloro-2-propyl) phosphate) is typically used in polyurethane and polyisocyanurate foams in concentrations of up to 10%. TCPP is a potential carcinogen, accumulates in the liver and kidneys, and may affect the developing nervous system. TCPP is found globally in water and wildlife.
Presence of halogenated flame retardants in foam plastic can increase production of toxic dioxins, furans, and other combustion byproducts during a fire. These byproducts may be contributing to the increased incidence of cancer in fire fighters.
Halogenated flame retardants including HBCD and TCPP are found globally in water and wildlife.
Building insulation is thought to account for about 87% of all HBCD releases to the environment. Manufacturing, landfilling, incineration, and recycling all lead to environmental release of these persistent flame retardants and their toxic combustion byproducts.
Halogenated flame retardants can be found in Top of the Food chain predators world wide.
- Green Science Policy (pdf): Flame Retardants in Insulation Materials Fact Sheet
- Buildinggreen.com article: Basics of Brominated Flame Retardants
- You can find additional information about flame retardant chemicals on Green Science Policy Institute’s website.
- Collaborative on Health and the Environment article: Flame Retardants.