Brominated flame retardants toxicity

Simonsen, E. A., Moller, L. M., Madesn, T., and Stavnsbjerg, M., Brominated flame retardants toxicity and ecotoxicity. Project No. 568, Danish Environmental Protection Agency, 2000. 

The Brominated Flame Retardants Industry Panel (BFRIP) was formed ia 1985 within the Flame Retardant Chemicals Association (FRCA) to address such concerns about the use of decabromodiphenyl oxide. Siace 1990 the BFRIP has operated as a Chemical Self-Funded Technical Advocacy and Research (CHEMSTAR) panel within the Chemical Manufacturers Association (CMA) (64). As of 1993, members of BFRIP are Ak2o, Amerihaas (Dead Sea Bromine Group), Ethyl Corp., and Great Lakes Chemical. Siace its formation, BFRIP has presented updates to iadustry on a regular basis (65,66), and has pubhshed a summary of the available toxicity information on four of the largest volume brominated flame retardants (67,68) tetrabromo bisphenol A, pentabromodiphenyl oxide, octabromodiphenyl oxide, and decabromodiphenyl oxide. This information supplements that summarized ia Table 11. 

In addition, the concern about e-waste not only focuses on its vast quantity generated daily, but also more on the need to handle the toxic chemicals embedded in it. It is well known that e-waste contains lead, beryllium, mercury, cadmium (Cd), and brominated flame retardants (BFRs) among other chemical materials [3]. Furthermore, highly toxic chemicals such as polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and polybrominated dibenzo-p-dioxins and dibenzo-furans (PBDD/Fs) can be formed during the recycling process [4]. 

PBDEs are a class of brominated flame retardants (BFRs) used in textiles, plastics and electronic products. The effects of BFRs are associated with three commercial mixtures of PBDEs decaBDE, octaBDE and pentaBDE. In laboratory animal experiments, the toxicity of PBDEs was linked to damage to liver function and,... 

It is not possible to achieve "adequate control" of the risks of persistent, bioaccumulative chemicals. The fact that traditional risk assessment cannot reasonably be applied to such chemicals, and that a revised PBT (persistent, bioaccumulative, toxic) assessment is necessary, is explicitly recognised in the EU s Technical Guidance Document for risk assessment. Their intrinsic properties mean that there is a high risk of exposure at sometime during the lifecycle of the chemical or the article that contains it. Even small releases, if they are continuous, can result in significant exposures. This is why we see significant and, in some cases, escalating levels of brominated flame retardants, nonylphenols and other persistent chemicals in breast milk, umbilical cord blood and human tissue. 

As concern around bromine compounds grew, industry moved away from those underthe greatest legislative pressure (PBDEs and PBBs) towards other bromine compounds such asTBBP-Aand HBCD. Meanwhile, understanding of the toxicity and persistence of TBBP-A and HBCD has increased the pressure to address brominated flame retardants as a... 

Saegusa Y, Fujimoto H, Woo GH, Inoue K, Takahashi M, Mitsumori K, Hirose M, Nishikawa A, Shibutani M (2009) Developmental toxicity of brominated flame retardants, tetrabromo-bisphenol A and 1,2,5,6,9,10-hexabromocyclododecane, in rat offspring after maternal exposure from mid-gestation through lactation. Reprod Toxicol 28 456-467... 

The POCs include, but are certainly not limited to the polychlorinated biphenyls (PCBs) and the organochlorine pesticides, including those in current use, restricted use and historic use brominated flame retardants including polybrominated diphenyl ethers PAHs and the sometimes more toxic transformation products of these chemicals. Table 1 summarizes information on some of the POCs more commonly detected in alpine environments. 

Material balances for the pyrolysis products from HIPS equipped with flame retardants have been given (53). The pyrolysis experiments were performed to some extent in the presence of zeolite catalysts. The zeolites were added in order to remove organic bromine from the products of pyrolysis. In addition to their potential of destroying toxic brominated flame retardants, zeolites have been believed to be suitable to upgrade the pyrolysis products. 

PBDEs Considered the new PCBs, polybrominated diphenyl ethers are a group of brominated flame retardants used in lots of products, including the foam in couches and mattresses, and plastic TV and computer monitors (Dell and HP, among others, have banned them). One of the reasons PBDEs are so hard to avoid is that they re not bound to the molecules in materials, so toxic residue can escape in the form of dust. Most kinds of PBDEs have been banned in Europe since 2004, and American women carry ten to seventy times as many PBDEs in their breast milk, tissues, and blood as Europeans do. Exposure to PBDEs during fetal development can negatively affect how the brain functions. 

Darnerud, P.O., 2003. Toxic effects of brominated flame retardants in man and in wildlife. Environ. Int. 29, 841-853. 

TG-MS is an ideal technique for identifying residual volatiles in polymers. The detection of residual volatiles (and of other impurities) can often yield clues as to manufacturing processes. In many cases, such as in the determination of highly volatile materials, of residual solvents or plasticisers, use of TG-MS is requested. Specifically, there are reports on the entrapment of curing volatiles in bismaleimide laminates [145] and elastomers [48], on the detection of a curing agent (dicumylperoxide) in EPDM rubbers and of bromine flame retardants in electronic waste [50], of plasticisers such as bambuterol hydrochloride [142] or TPP and diethylterephthalate in cellulose acetate [143], on solvent extraction and formaldehyde loss in phenolic resins [164], and on the evolution of toxic compounds from PVC and polyurethane foams [146]. 

In response to the continuing discovery of the persistence, bioaccumulative properties, and toxicity of POPs, regional, national and international policies ban the intentional production of compounds, such as polychlorinated biphenyls (PCBs), several organochlo-rine pesticides, such as mirex and dieldrin, and the brominated flame retardants poly-brominated diphenyl ethers (penta-BDE and octa-BDE, and most recently, deca-BDE). Policies and programs have also targeted the unintentional production and release of POPs such as polychlorinated dibenzodioxins and furans (PCDD/Fs). Evidence of the success of these policies has been seen in immediate reductions of air concentrations, followed by declining concentrations in water bodies, soils, biota and our food supplies... 

However, especially brominated flame retardants are creating problems when electronic and electrical equipment reach end of life. If landfilled, toxic brominated flame retardants may slowly leach ont into the groundwater, where they persist for several years or they can evolve into the air. If waste materials are burned toxic polybrominated dioxins and furans can be formed [53, 50]. 

A disadvantage of brominated flame retardants is that PBDDs and PBDFs may be formed during combustion. Little is known about the toxicity of PBDDs and PBDFs. They are estimated to be in the same order as those of PCDD and PCDF [2,3]. 

In summary, it can be concluded that the acute toxicity of brominated flame retardants is relatively low. The long term effects on the balance of endocrine systems seems to present the greatest danger of these compounds. These endocrine effects need further consideration, since the majority of animals and man are exposed to these brominated flame retardants. The exposure range for humans via the food was calculated as 0.2-0.7 mg per day [96]. 

U.S. Agency for Toxic Chemicals and Disease Registry, Toxicological Profile for Chlorinated Dibenzo-p-Dioxins. Available at http //www.atsdr.cdc.gov/toxprofiles/tpl04.html (accessed September 2004). "fij.S. EPA, Brominated Flame Retardants to be Voluntarily Phased Out. Available at http //yosemite.-epa.gov/opa/admpress.nsf/0/26f9f23c42cd007d85256dd4005525d2 OpenDocument (accessed... 

G. Lyons, Brominated Flame Retardants, WWF Toxics Programme, May 1999. 

CPs are aliphatic compounds that differ in physical-chemical characteristics from other widely studied aromatic hydrocarbons such as polychlorinated biphenyls (PCBs), brominated flame retardants and dioxins. Unlike the aromatic hydrocarbons for which important receptor-based mechanisms of toxicity have been elucidated, CP toxicity studies have been carried out mainly with complex technical mixtures and little is known of their toxic mechanisms. In addition, these technical... 

In the case of additives such as brominated flame retardants, whose toxicity is proved, spectroscopic sorting allows materials containing these toxic additives to be removed from the recycling process. These will be specifically treated. When the toxicity of chemical products is questioned by the European Union REACH regulation, we find that recycled materials are poorly defined, with additives often appearing on lists of problematic molecules. Furthermore, the chemical structure of organic additives may alter, particularly under the effect of oxidation and UV rays. 

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