Chemical flame retardants: New study highlights chemical exposure risk from household furniture


Chemical substances are added to furniture and furnishings in the UK to help prevent fires and limit their spread. However, as these chemicals are being increasingly linked to harmful health and environmental effects, many are calling for alternatives to achieving fire safety. A new study1 investigates how contact with our furniture could increase our exposure to potentially harmful flame retardant chemicals.

 

What are chlorinated organophosphate flame retardants and why are they used?

Flame retardants are industrial chemicals that are widely used in buildings, cars, electronics and furniture to meet fire safety regulations, but this is not where they stay. These chemicals commonly leak out of materials during use and disposal, getting into people and the environment. Once in the environment flame retardants don’t break down, in fact they accumulate along food chains and build up to potentially harmful concentration levels within people and wildlife.

A new sub-group of flame retardants, known as chlorinated organophosphate flame retardants (Cl-PFRs), have widely replaced a previous sub-group known as Polybrominated Diphenyl Ethers (PBDEs) flame retardants2, as CI-PFRs were presumed to be less harmful3. The production of PBDEs ceased across the UK in 1996 due to evidence of their toxicity, bioaccumulation (ability for concentrations to build up inside the bodies of living organisms) and persistence in the environment4. Despite almost 30 years passing by since PBDEs use, these chemicals are still present in soils, sediments and waterbodies, presenting a continued threat to wildlife5,6. Now similar health and environmental concerns are being identified for chlorinated organophosphate flame retardants, and with CI-PFRs being found at higher levels than peak PBDE levels, this is a real concern for both public and environmental health3. We are now in a position where growing research is highlighting the hazardous potential of CI-PFRs7. Despite building evidence from toxicity testing, epidemiology case studies and risk assessments indicating health concerns associated with exposure, CI-PFRs are not currently regulated.

 

The latest findings

The research by Dr Abdallah and Dr Harrad1 at the University of Birmingham provides the first experimental data on the absorption via skin contact with furniture fabrics of three compounds from the CI-PFR group; tris-(2-chloroethyl)-phosphate (TCEP), tris-(1-chloro-2-propyl)-phosphate (TCIPP) and tris-(1,3-dichloropropyl)-phosphate (TDCIPP). All three chemical flame retardants are classed as hazardous substances by the EU, this means the substance has one or more potential properties of harm8. The TCEP compound is classed as a substance of very high concern (SVHC) because it is toxic to reproduction and aquatic life9. In addition to this, both TCEP and TDCIPP have been associated with increased risk of cancer and the EU has listed them as ‘potential human carcinogen’ and ‘suspected of causing cancer’, respectively10. Yet we continue to rely upon them in UK manufacturing.

The study used fabric samples from UK upholstered furniture (a home armchair, home sofa and an office armchair), known to contain measurable high concentrations of the three CI-PFRs. The CI-PFRs were bioavailable (absorbable) through skin contact when tested. The study explored two exposure scenarios, summer and winter. The summer scenario assumes that a higher surface area of skin to furniture contact occurs increasing the risk of absorption, the winter scenario assumes only the palms of someone’s hands would be exposed to the furniture fabrics. TCEP was the most permeable substance, followed by TCIPP, then TDCIPP1. In adults ‘dietary intake was the major pathway of exposure of all CI-PFRs, while dust ingestion was the predominant pathway in toddlers’, the second highest exposure pathway of TCIPP, for adults and toddlers, was absorption through skin in summer months1. Although both TCEP and TDCIPP had significant exposure pathways, the daily contribution through skin absorption was lower1.

The study’s use of different real-life scenarios and the varying degrees of skin exposure to CI-PFRs highlights that direct skin contact with consumer products containing chemical flame retardants should be considered as a potentially significant human exposure pathway. Future risk assessments therefore need to consider direct skin exposure of flame retardants in furniture. Awareness of the risks will ultimately help us to make better informed decisions for our own health and the environment we live in.

 

‘Dermal uptake of flame retardants from direct contact with consumer products has been largely overlooked, where most studies focused on ingestion and inhalation. Our research has recently highlighted the importance of this exposure pathway after proving the absorption of flame retardant chemicals through human skin to reach the blood stream. This raises more concern over the use of hazardous flame retardant chemicals in products such as furniture fabrics, beddings and mattress covers, which come in contact with bare skin for prolonged times, particularly during summer’ – Dr Abdallah

How can we act on this research?

Here at Fidra we are working closely with industry and regulators to update and improve UK fire safety requirements. We want to see an increase in chemical transparency along supply chains and a revision of the current UK Furniture and Furnishings Fire Safety Regulations to support healthier and more sustainable fire safety. By bringing the UK fire safety regulations in line with other countries, we can achieve greater fire safety for the UK public, cut the unnecessary use of harmful chemical flame retardants, drive UK innovation towards intelligent product design, and protect the public and environment from the growing impact of chemical pollution.  To find out more check out our recently launched sustainable fire safety webpage.

 

References

[1] Abou-Elwafa Abdallah, M., & Harrad, S. (2022). Dermal uptake of chlorinated organophosphate flame retardants via contact with furniture fabrics; implications for human exposure. Environmental Research, 209, 112847. https://doi.org/10.1016/j.envres.2022.112847

[2] Phillips, A. L., Hammel, S. C., Konstantinov, A., & Stapleton, H. M. (2017). Characterization of Individual Isopropylated and tert -Butylated Triarylphosphate (ITP and TBPP) Isomers in Several Commercial Flame Retardant Mixtures and House Dust Standard Reference Material SRM 2585. Environmental Science & Technology, 51(22), 13443–13449. https://doi.org/10.1021/acs.est.7b04179

[3] Blum, A., Behl, M., Birnbaum, L. S., Diamond, M. L., Phillips, A., Singla, V., Sipes, N. S., Stapleton, H. M., & Venier, M. (2019). Organophosphate Ester Flame Retardants: Are They a Regrettable Substitution for Polybrominated Diphenyl Ethers? Environmental Science & Technology Letters, 6(11), 638–649. https://doi.org/10.1021/acs.estlett.9b00582

[4] Sharkey, M., Harrad, S., Abou-Elwafa Abdallah, M., Drage, D. S., & Berresheim, H. (2020). Phasing-out of legacy brominated flame retardants: The UNEP Stockholm Convention and other legislative action worldwide. Environment International, 144, 106041. https://doi.org/10.1016/j.envint.2020.106041

[5] Morrissey, C. A., Stanton, D. W. G., Tyler, C. R., Pereira, M. G., Newton, J., Durance, I., & Ormerod, S. J. (2014). Developmental impairment in eurasian dipper nestlings exposed to urban stream pollutants. Environmental Toxicology and Chemistry, 33(6), 1315–1323. https://doi.org/10.1002/etc.2555

[6] Windsor, F. M., Pereira, M. G., Tyler, C. R., & Ormerod, S. J. (2019). Biological Traits and the Transfer of Persistent Organic Pollutants through River Food Webs. Environmental Science & Technology, 53(22), 13246–13256. https://doi.org/10.1021/acs.est.9b05891

[7] ARCADIS. (2011). European Commission Health & Consumers DG – Identification and evaluation of data on flame retardants in consumer products. https://www.europeanfiresafetyalliance.org/publications/identification-and-evaluation-of-data-on-flame-retardants-in-consumer-products/

[8] EU Risk Assessment Reports. (2008). Annex XV reports of existing substance risk assessment and risk reduction strategies. https://echa.europa.eu/information-on-chemicals/transitional-measures/annex-xv-transitional-reports?diss=true&search_criteria_ecnumber=237-158-7&search_criteria_casnumber=13674-84-5&search_criteria_name=Tris%282-chloro-1-methylethyl%29+phosphate

[9] European Union. (2009). European Union Risk Assessment Report. Tris(2-chloroethyl)phosphate, TCEP. CAS 11-96-8; EINECS 204-118-5. https://echa.europa.eu/documents/10162/2663989d-1795-44a1-8f50-153a81133258

[10] ECHA. (n.d.). European Chemicals Agency –  Substance information: Substance infocard. Retrieved May 24, 2022, from https://echa.europa.eu/substance-information/-/substanceinfo/100.003.744

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