Polybrominated Diphenyl Ethers (PBDEs)
At a Glance
PBDEs are a class of compounds used as flame retardants.
They are endocrine disrupting compounds associated primarily with thyroid disruption. Some evidence also links them to breast cancer.
What are polybrominated diphenyl ethers?
PBDEs are flame retardant chemicals found in household and industrial products.[1],[2] They are closely related to polybrominated biphenyls (PBBs), which the International Agency for Research on Cancer (IARC) classifies as probably carcinogenic to humans.[3]
Where are polybrominated diphenyl ethers found?
Polybrominated diphenyl ethers are found in consumer products such as furniture, plastic, electronics, and fabric.[4],[5] PBDEs pollute the environment and can bioaccumulate.[6] They have been found in water, animal products, birds, fish, human tissue, breast milk, soil, dust and the air.[7],[8]
What evidence links polybrominated diphenyl ethers to breast cancer?
PBDEs affect a number of hormonal systems, including the androgen, progestin and estrogen systems, although the system most strongly affected by PBDEs is the thyroid hormone system.[9]
- Researchers in China measured 14 different PBDEs in fat tissues of women with breast cancer as well women without the disease. Higher levels of most individual PBDEs and higher levels of all PBDEs combined were associated with increased risk for breast cancer.[10]
- Breast cancer cells exposed to the polybrominated diphenyl ether penta-BDE showed increased growth. The chemical acted like estrogen in promoting proliferation of the cancer cells.[11]
- Various PBDEs in breast cancer cells displayed estrogen-like qualities and amplified the growth of the cells.[12]
- Exposure of human breast cancer cells to BDE-47, one of the most common PBDEs found in people’s bodies, led to an increase in oxidative stress, a process that has been associated with increased risk for breast cancer.[13]
- PBDEs may affect both estrogen and thyroid hormone processes in ways that could increase the risk of breast cancer.[14],[15]
- In breast cancer cells treated with PBDE-209 and an anti-cancer drug (tamoxifen), the PBDE neutralized the effects of the drug.[16]
In addition,
- PBDEs disrupt thyroid hormone levels, impacting brain development.[17]
- Rodents exposed to PBDE-209 had an increased incidence of thyroid tumors.[18]
Who is most likely to be exposed to polybrominated diphenyl ethers?
Everyone is exposed to PBDEs through household products.[19],[20] However, people with certain occupations, such as firefighting, may be exposed to PBDEs more often and at higher concentrations.[21] Since 2004, many PBDEs have been phased out of use,[22] but replacement chemicals also present health concerns and data gaps.[23],[24]
Who is most vulnerable to the health effects?
The health effects of certain PBDEs, such as BDE-47, are dose-dependent.[25] Anyone who is repeatedly exposed to large doses of PBDEs is more susceptible to the toxic effects. For example, firefighters are more vulnerable to the health effects, as they regularly encounter PBDEs in high concentrations.[26]
What are the top tips to avoid exposure?
- Choose products that are free of chemical flame retardants.[27],[28],[29] The Natural Resources Defense Council has researched major furniture retailers and offers a report card on their flame-retardant policies.
- Clean with a moist cloth to avoid putting PBDE-containing dust in the air.[30]
- Use a HEPA filter on air conditioning vents and vacuums.[31]
- Wash your hands frequently. One study found that handwashing reduced office exposures to PBDEs.[32]
Other Resources:
- Natural Resources Defense Council (NRDC) furniture shopping guides
- Center for Environmental Health (CEH) guide to baby products without flame retardants
- CEH flame retardant FAQs
Updated 2019
[2] Environmental Protection Agency. “Technical Fact Sheet: Polybrominated Diphenyl Ethers (PBDEs).” Last modified November 2017. https://www.epa.gov/sites/production/files/2014-03/documents/ffrrofactsheet_contaminant_perchlorate_january2014_final_0.pdf
[3] Environmental Protection Agency. “Technical Fact Sheet: Polybrominated Diphenyl Ethers (PBDEs).” Last modified November 2017. https://www.epa.gov/sites/production/files/2014-03/documents/ffrrofactsheet_contaminant_perchlorate_january2014_final_0.pdf
[4] Costa, Lucio G, and Gennaro Giordano. “Developmental neurotoxicity of polybrominated diphenyl ether (PBDE) flame retardants.” Neurotoxicology 28, 6 (2007): 1047-67. doi:10.1016/j.neuro.2007.08.007.
[5] Environmental Protection Agency. “Technical Fact Sheet: Polybrominated Diphenyl Ethers (PBDEs).” Last modified November 2017. https://www.epa.gov/sites/production/files/2014-03/documents/ffrrofactsheet_contaminant_perchlorate_january2014_final_0.pdf
[6] Costa, Lucio G, and Gennaro Giordano. “Developmental neurotoxicity of polybrominated diphenyl ether (PBDE) flame retardants.” Neurotoxicology 28, 6 (2007): 1047-67. doi:10.1016/j.neuro.2007.08.007.
[7] Environmental Protection Agency. “Technical Fact Sheet: Polybrominated Diphenyl Ethers (PBDEs).” Last modified November 2017. https://www.epa.gov/sites/production/files/2014-03/documents/ffrrofactsheet_contaminant_perchlorate_january2014_final_0.pdf
[8] Costa, Lucio G, and Gennaro Giordano. “Developmental neurotoxicity of polybrominated diphenyl ether (PBDE) flame retardants.” Neurotoxicology 28, 6 (2007): 1047-67. doi:10.1016/j.neuro.2007.08.007.
[9] Costa, Lucio G et al. “Polybrominated diphenyl ether (PBDE) flame retardants: environmental contamination, human body burden and potential adverse health effects.” Acta Bio-Medica 79, 3 (2008): 172-83.
[10] He Y et al. “Adipose tissue levels of polybrominated diphenyl ethers and breast cancer risk in Chinese women: A case-control study.” Environmental Research 167 (2018): 160-168. doi:10.1016/j.envres.2018.07.009.
[11] Yu, Lin and Ping Zhan. “Molecular mechanisms underlying proliferation and apoptosis in breast cancer MCF-7 cells induced by pentabrominated diphenyl ethers.” Toxicological and Environmental Chemistry 91, 4 (2009): 665-670. doi:10.1080/02772240802343370.
[12] Meerts, I A et al. “In vitro estrogenicity of polybrominated diphenyl ethers, hydroxylated PDBEs, and polybrominated bisphenol A compounds.” Environmental Health Perspectives 109, 4 (2001): 399-407. doi:10.1289/ehp.01109399.
[13] Wei J et al. “Metabolic profiling on the effect of 2,2′,4,4′-tetrabromodiphenyl ether (BDE-47) in MCF-7 cells.” Chemosphere 192 (2018): 297-304. doi:10.1016/j.chemosphere.2017.10.170.
[14] Davis, Faith B. et al. “Similar and Shared Nongenomic Mechanisms of Action of Estrogen and Thyroid Hormone.” Immunology, Endocrine & Metabolic Agents in Medicinal Chemistry 9 (2009): 84. doi:10.2174/187152209789000696.
[15] Shaw, Susan D et al. “Halogenated flame retardants: do the fire safety benefits justify the risks?.” Reviews on environmental health vol. 25,4 (2010): 261-305. doi:10.1515/reveh.2010.25.4.261
[16] Li, Zhi-Hua et al. “Effects of decabrominated diphenyl ether (PBDE-209) in regulation of growth and apoptosis of breast, ovarian, and cervical cancer cells.” Environmental Health Perspectives 120, 4 (2012): 541-6. doi:10.1289/ehp.1104051.
[17] Costa, Lucio G et al. “Polybrominated diphenyl ether (PBDE) flame retardants: environmental contamination, human body burden and potential adverse health effects.” Acta Bio-Medica 79, 3 (2008): 172-83.
[18] Costa, Lucio G et al. “Polybrominated diphenyl ether (PBDE) flame retardants: environmental contamination, human body burden and potential adverse health effects.” Acta Bio-Medica 79, 3 (2008): 172-83.
[19] Costa, Lucio G, and Gennaro Giordano. “Developmental neurotoxicity of polybrominated diphenyl ether (PBDE) flame retardants.” Neurotoxicology 28, 6 (2007): 1047-67. doi:10.1016/j.neuro.2007.08.007.
[20] Environmental Protection Agency. “Technical Fact Sheet: Polybrominated Diphenyl Ethers (PBDEs).” Last modified November 2017. https://www.epa.gov/sites/production/files/2014-03/documents/ffrrofactsheet_contaminant_perchlorate_january2014_final_0.pdf
[21] Committee on Environment and Public Works, United States Senate. “Oversight of EPA Authorities and Actions to Control Exposures to Toxic Chemicals.” Government Publishing Office, Senate Hearing 112-974, USA, 2012. https://www.govinfo.gov/content/pkg/CHRG-112shrg25110/html/CHRG-112shrg25110.htm.
[22] Dodson, Robin E et al. “After the PBDE phase-out: a broad suite of flame retardants in repeat house dust samples from California.” Environmental Science & Technology 46, 24 (2012): 13056-66. doi:10.1021/es303879n.
[23] Patisaul, Heather B et al. “Accumulation and endocrine disrupting effects of the flame retardant mixture Firemaster® 550 in rats: an exploratory assessment.” Journal of Biochemical and Molecular Toxicology 27, 2 (2013): 124-36. doi:10.1002/jbt.21439.
[24] Dodson, Robin E et al. “After the PBDE phase-out: a broad suite of flame retardants in repeat house dust samples from California.” Environmental Science & Technology 46, 24 (2012): 13056-66. doi:10.1021/es303879n.
[25] Emond, Claude et al. “Proposed mechanistic description of dose-dependent BDE-47 urinary elimination in mice using a physiologically based pharmacokinetic model.” Toxicology and Applied Pharmacology 273, 2 (2013): 335-44. doi:10.1016/j.taap.2013.09.007.
[26] Committee on Environment and Public Works, United States Senate. “Oversight of EPA Authorities and Actions to Control Exposures to Toxic Chemicals.” Government Publishing Office, Senate Hearing 112-974, USA, 2012. https://www.govinfo.gov/content/pkg/CHRG-112shrg25110/html/CHRG-112shrg25110.htm.
[27] Environmental Working Group. “EWG’s Tips to Avoid Flame Retardants.” Last modified January 2018. https://static.ewg.org/ewg-tip-sheets/EWG_FlameRetardantTips.pdf?_ga=2.160798141.1250833342.1605211938-994589842.1603472780
[28] Natural Resources Defense Council. “Fact Sheet: Safer Sofas: How do major furniture stores compare.” Last modified 2014. https://www.nrdc.org/sites/default/files/safer-sofas-FS.pdf.
[29] Center for Environmental Health. Tips: Reduce Your Exposure to Flame Retardant Chemicals.” Accessed November 12, 2020. https://www.ceh.org/wp-content/uploads/2019/07/FR-Tips-Sheet.pdf.
[30] Pediatric Environmental Health Specialty Units. “PBDEs: Information for Pediatric Health Professionals.” Last modified May 10, 2010. https://deohs.washington.edu/sites/default/files/documents/PBDE_Health_Professionals_Factsheet_May_2010.pdf.
[31] Pediatric Environmental Health Specialty Units. “PBDEs: Information for Pediatric Health Professionals.” Last modified May 10, 2010. https://deohs.washington.edu/sites/default/files/documents/PBDE_Health_Professionals_Factsheet_May_2010.pdf
[32] Watkins, Deborah J et al. “Exposure to PBDEs in the office environment: evaluating the relationships between dust, handwipes, and serum.” Environmental Health Perspectives 119, 9 (2011): 1247-52. doi:10.1289/ehp.1003271.
[33] Natural Resources Defense Council. “Fact Sheet: Safer Sofas: How do major furniture stores compare.” Last modified 2014. https://www.nrdc.org/sites/default/files/safer-sofas-FS.pdf.
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