Case Study Brominated Flame Retardants

Phosphorus -bromine flame retardant synergy was demonstrated in a 2/1 polycarbonate/polyethylene blend. These data also show phosphorus to be about ten times more effective than bromine in this blend. Brominated phosphates, where both bromine and phosphorus are in the same molecule, were also studied. In at least one case, synergy is further enhanced when both phosphorus and bromine are in the same molecule as compared with a physical blend of a phosphorus and a bromine compound. On a weight basis, phosphorus and bromine in the same molecule are perhaps the most efficient flame retardant combination. The effect of adding an impact modifier was also shown. 

The information was compiled from paper and on-line research and from direct phone conversations and meetings with industry representatives. The more comprehensive overview of case studies of company substitutions for brominated flame retardants demonstrates both the complexity and feasibility of implementing safer alternatives. Other case studies show how leading retailers are moving to phase-out hazardous materials and how some chemical industries are researching and implementing Green Chemistry alternatives. 

The selective treatments of flame-retardant plastics are fulfilled when the WEEE plastics are treated (recovered, recycled, thermally disposed) together with other wastes, as is the case with energy recovery processes that are currently practiced in Europe.78 79 In this scenario, the joint recovery of plastics containing brominated flame-retardants with other materials complies with the purpose of the WEEE Directive without the removal requirement of Annex II. Recent technical studies and legal reviews demonstrate that WEEE plastics containing brominated flame-retardants are compatible with the EU WEEE Directive without separation and removal prior to the waste treatment. This has been confirmed by the 2006 EU Member States guidance on the separation requirements of the WEEE Directive.80... 

The final use of chemical products can result in the release of hazardous substances affecting man and the environment. Chemicals can be released from products used in the indoor environment, released to the atmosphere when a product is used outside, and released to groundwater if the chemicals leach out of a product in a landfill. Data are extremely limited on how many chemical products there are on the market today, on their chemical content, and on whether - and how - they may be releasing hazardous substances to the environment. Recent studies have shown that, in some cases, the majority of emissions released during the entire lifecycle occur during the service life of the product, rather than during production. A study conducted by TNO estimated that over 75 percent of total emissions to the environment from phthalates in plastics, brominated flame retardants in plastics, and zinc from tires occurred during the service life (TNO, 2001). 

The saga of brominated flame retardants offers a cautionary tale for the chemical industry.65 These chemicals, developed in the early 1970s, are used in a wide range of consumer products, such as furniture, foam, and plastic casings of electronic devices. In 1998, Swedish scientists reviewing archived human breast milk samples discovered that certain flame retardant chemicals (polybrominated diphenyl ethers, or PBDEs) had doubled in concentration in Swedish breast milk about every five years over the preceding twenty. This was a source of concern, as studies of laboratory animals had shown that PBDEs dismpt thyroid hormones. Such dismption yields neurobehavioral effects similar to those of PCBs (polychlorinated biphenyls), whose manufacture the United States banned in 1976. 

Emerging Contaminants in the Water-sediment System Case Studies of Pharmaceuticals and Brominated Flame Retardants in the Ebro River Basin... 

Case Study 2 Occurrence, Fate and Behaviour of Brominated Flame Retardants 291... 

CASE STUDY 2 OCCURRENCE, FATE AND BEHAVIOUR OF BROMINATED FLAME RETARDANTS IN THE EBRO RIVER BASIN... 

As part of the project work plan, this protocol was tested in three case studies designed to match the three levels of vafidation, before preparation of the final version. The interlaboratory studies included analyses of i) selected natural and synthetic oestrogens and oestrogenic activity in wastewater, ii) pharmaceuticals in water and iii) brominated flame retardants in dust. The design of the interlaboratory studies, analytical protocols and final reports from the interlaboratory studies are available on the project web site. The final aim is flie implemenfation of the protocols in the fields of European standardisation and European legislation. To this purpose, negotiations will be initiated to launch New Work Item proposals at CEN level (see Eigure 8.1.5). 

With a recent push toward non-brominated flame retardants, phosphorus-based alternatives, such as phosphate esters, are used more frequently for various applications. Their use as plasticizers is also well known. However, their function as environmental stress crack agents of various thermoplastics is less well recognized. Two case studies, one - in which a triaryl phosphate was a component of the formulation, the other - in which it was migrating from an adjacent component illustrate some of the problems with their use. Fractographic analysis and various analytical techniques were used to determine a root cause of each of the two failures. 

The Bromine Industry in particular, points out that non-brominated chemical flame retardants may be very hazardous and that the phase-out of BFRs may not be safe. The non-brominated alternatives listed in the above case studies are likely to be safer if they exhibit less persistence and bioaccumulation in living systems, but some do possess significant toxicity. In the last few years, some agencies have therefore investigated the relative merits of alternatives to BFRs. 

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