The annual PAH emissions for the worst-case, calculated over the sofa’s whole life cycle (manufacture, accidental fires, disposal) correspond to less than 1% of all the PAH emissions expected only from fires each year (using data available from Sweden).
Total hydrocarbon (HC) and volatile organic carbon (VOC) emissions are similar for all three types of furniture.
kg/million sofas 0.00035 0.0003 0.00025 0.0002 0.00015 0.0001 0.00005 0
Furniture prod Repl Prod Landfill Incineration Heat Recovery FR production fire Total
TBDD-equivalent emissions for 1 million sofas over their 10 year life cycle.
TCDD-equivalent emissions for 1 million sofas over their 10 year life cycle.
HCl, TCDD-equivalent and TBDD-equivalent emissions are all higher for the FR furniture, due both to the effect of emissions from incineration and from fires. The calculation of emissions from incineration was made using the assumption that emissions were proportional to chlorine/bromine levels in furniture, which may result in an overestimation. This assumption results in differences between FR and non-FR sofas of approx. 2.3 mg/million sofas/year total TCDD (0.0000023 kg/year) and 29 mg/year total TBDD (0.000029 kg/year).
The total sofa TCDD emissions calculated for the worst-case over the whole life cycle (manufacture, accidental fires, disposal) correspond to approx. 0.003% of total annual TCDD emissions from all sources in UK. Similar data is not available for TBDD-equivalent emission.
Evaluation of cancer risk from emissions data
Like all Life Cycle Assessments, this study has generated data for a number of environmental factors of different natures, which cannot be directly compiled into one comparison. Because there were limited differences between FR and non-FR furniture for general indicators such as energy consumption, the emissions of toxic pollutants during furniture manufacture/ use/ disposal and during fires appeared as the most significant comparative factor. In particular, the perceived cancer risk related to emissions appears as a prominent public concern concerning chemical use, and therefore a method was developed to allow an overall indication of this to be derived from the data for relevant pollutants (PAH, TCDD, TBDD). This was done using the method generally accepted for dioxins/furans, that is all TCDD/F and TBDD/F species were calculated as toxicity equivalents of units of the most toxic species of this group; the same was done for the group of PAHs, then the
t w o w e r e c o m b i n e d b y w e i g h t i n g b y t h e r e l a t i v e c a r c i n o g e n i c i t y ( i . e . , u n i t r i s k f a c t o r 7 ) . T h i s enabled an overall sum cancer risk to be evaluated for comparison of FR and non-FR furniture.
7 Spindler, E.J., "Soot from fires – A risk assessment" Chemische Technik, 49(4), pp 193-196 (1977). Available in German only.