Brominated flame retardants - PBB and PBDE

Brominated flame retardants (BFRs), PBB and PBDE have been targeted by RoHS legislation as they are suspected to be carcinogenic. The 2002/95/EC Directive limits the maximum level of PBB and PBDE to 1000 ppm.

Options for Testing and Measuring

• XRF can be used to measure elemental Br up to 750 ppm; however, it does not measure specific Br compounds; so, if Br readings exceed (for example) 350 ppm* , additional testing is required.Brominated flame retardants contain at least 50% of elemental bromine. Therefore, to screen PBB or PBDE with XRF against regulatory threshold of 1000 ppm, we need to accept the threshold for Br at below 500 ppm level in order to reflect the Br fraction of flame retardant compound.
• FTIR can also be used for screening, specifically for PBB and PDBE. While the limits of detection are >20,000 ppm (i.e. above the RoHS limits), flame retardants typically are added at a rate concentration of 5-10% by weight, so FTIR can be used as a quick and non destructive qualitative screening, e.g. if FTIR results indicate levels >20,000 ppm, the sample fails RoHS compliance.
• If the results are inconclusive based upon the screening methods outlined above, then additional testing is required. The sample needs to be dissolved and analyzed with a more sensitive technique, either HPLC-UV or GC/MS.
• Thermo Fisher Scientific offers two excellent choices for GC MS: the DSQ is rugged single quadrupole instrument, while the PolarisQ GC-MSⁿ provides maximum sensitivity. The Finnigan Surveyor Plus HPLC is an alternative, effective technique as well.

Where is it used
Brominated additives have been used for years in commercially available plastics to make the polymers flame retardant.