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Investigation of brominated flame retardants present in articles being used, recycled and disposed of in New Zealand

• Executive Summary
• 1. Introduction
• 2. Estimate of the amount of BDE in New Zealand
• 3. Assessment of the fate of BDEs in waste
• 4. Profile of BDE flows in New Zealand
• 5. Risk analysis
• 6. Environmentally sound disposal methods
• 7. Limitations of the study
• 8. Conclusions and Recommendations
• Additional readings
• Appendix A Detailed data tables
• Appendix B Polybrominated Diphenyl Ether (PBDE) structure and physical properties
• Appendix C Analytical equipment and procedures
• Appendix D Certificate of analysis
• Appendix E Methods and analysis of consumer products
• Appendix F Calculating the % BDE present in consumer products
• Appendix G Details of the selected landfills and the sampling of leachate
• Appendix H Current status of the flame retardant industry
• Appendix I Non-dust sources of BDEs more prominent human intake
• Appendix J Completed Questionnaire SC-4/19 for submission of information on new POPs in accordance with SC-4/19
• Appendix L Questionnaire for organisations that manufacture articles containing BFR’s
• Appendix M Excel spreadsheet entitled ‘XRF analyser raw data’
• Appendix N Excel spreadsheets entitled ‘NZ Statistics data giving categories with raw data’

Appendix F Calculating the % BDE present in consumer products

The steps below and summary shown in Figure F.1 describe the methodology of how the concentration in mg/kg of BDE found from the laboratory analysis of a selection of plastic samples were used to give a % BDE value for any plastic tested using the XRF.

1. The concentration of individual BDEs from lab analysis was converted into the concentration of bromine for that BDE by multiplying the % by mass of bromine (using molar masses) that is present in each of the BDEs. Thus the mg/kg value for each BDE is converted to a mg/kg of bromine value.
2. The total bromine present in the plastic is found by totalling the amount of bromine found in each of the different congeners for every BDE. The other BFRs present in the lab analysis such as HBCD, TBBP-A or the unknown were treated in the same way.
3. This calculated total bromine content should be directly related to the XRF value for that product. As can be seen from the results in Figure 2 (below) the correlation between the total bromine content in the laboratory analysis and the XRF analyser is not conclusive. Out of the sixteen plastics analysed 7 samples (BFR 1, 5, 6, 10, 11, 14, and 16) had ‘similar’ levels of bromine in both XRF and laboratory analysis. However, in the rest of the samples (BFR 2, 3, 4, 7, 8, 9, 12, 13, 15) negligible quantities of bromine were found in the laboratory analysis whereas significant quantities were identified by the XRF analyser. Establishing a correlation factor between the laboratory analysis and the XRF analyser is problematic with such limited and inconclusive data. However it was decided that those laboratory analysis that did not reveal any BDEs were treated as anomalous and were discarded. For example, sample BFR 2 a printed circuit board (5-10 yrs old) is known typically to contain quite high bromine as much as 20 % by weight (usually Tetrabromobisphenol A, TBBPA) yet the laboratory analysis reveals only 1 mg/kg. Obviously considerably more testing is required to establish the large discrepancy between some of the data obtained from the laboratory and the XRF analysis. Regardless of the cause it was deemed more prudent to be conservative and assume that either the laboratory extraction of the BDE from the plastic was incomplete or more likely the fact that the BDEs present in the plastic were different from the 21 BDE’s tested for by the laboratory analysis (There are 209 BDEs in total). This assumption does of course mean that the estimation of the BDE content in consumer products could be higher than the actual content.
4. The correlation factor was calculated by comparing the total of all the BDEs from the laboratory analysis from samples BFR 1, 10, 11, 14, and 16 (178,497 mg/kg) and comparing the corresponding total from the XRF analysis (384,520 mg/kg). This gives a correlation factor of 0.5 i.e. the laboratory analysis gives half the value of the XRF analyser. Samples BFR 5 and 6 were not included as these samples were expanded polystyrene and were known to contain hexabromododecane (HBCD).
5. If one assumes that the samples sent for laboratory analysis is a reflection of the types of plastics that are being used in the consumer products (which is a fair assumption) then the average of total BDE present in the consumer products can be found by multiplying the XRF value obtained by the 0.5 correlation factor.

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In Graph 2 the 4 samples near (0 ; 0) have low to medium levels of HBCD and penta-BDE while the two samples near the (90,000 ; 170,000) coordinate have very high deca-DBE levels.

Laboratory analysis ‘only’ determined 26 brominated compounds and identified some ‘unknown’ compounds, while there are over 300 brominated compounds either in use or associated with the production of BFRs, many of which will not come through the sample clean-up process. This explains the cluster of samples on the “0” mark for lab analysis Br content while the XRF analysis shows bromine present. To identify these compounds a more elaborate lab analysis would be needed.

The analytical results of the laboratory analysis are provided on the next page. The yellow highlighted sections indicate the ‘unknown peaks’ found in the chromatograms. The laboratory while they could not identify the unknowns, their concentration could be estimated as a multiple of the deca BDE peak (BDE209). Thus sample BFR16 (the CD stereo) has an unknown with an approximate concentration of twice the deca BDE (approx 2700 mg/kg).

Table 24 below summarises the 800 analyses taken of the various consumer products. The XRF % BDE is a weighted average figure that gives the likely percentage present in the various categories of consumer goods investigated. The correlation factor for the various consumer goods is applied to the NZ statistics database to establish the annual BDE flows in New Zealand.

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