Let’s talk about harmful chemicals and breast cancer

Why do so few organisations highlight the impact of harmful chemicals on breast cancer risk? Here at Breast Cancer UK, we aim to provide guidance on how to reduce your risk of breast cancer. Whether through lifestyle changes or by reducing your exposure to harmful chemicals found in everyday products and the environment.  

But why are we one of the very few cancer charities that focus on understanding how exposure to harmful chemicals could increase your breast cancer risk? In this blog, we discuss this question in more detail and explain some of the science behind our messages about chemicals.  

Breast cancer is a highly complex disease with many risk factors. Some can be influenced to decrease our overall risk of developing the disease during our lifetime. Not all risk factors are completely understood, but research is constantly evolving to better understand how certain factors contribute to an increased breast cancer risk.  

Here at Breast Cancer UK, we are dedicated to the prevention of breast cancer and believe that all risk factors are important. This includes raising awareness of those risk factors that are less well established, provided there is scientific evidence to support them.  

This is in direct contrast to other cancer charities that focus on well-established risk factors (such as age, family history, obesity and alcohol) and not those that may in the future be recognised as influencing breast cancer risk, such as long-term exposure to certain Endocrine Disrupting Chemicals (EDCs). 

What are EDCs, and why do we campaign for their restriction? 

EDCs are mostly synthetic compounds found in lots of everyday products and the environment, which can result in unintentional human exposures (1). Examples include bisphenols (e.g., BPA, BPS, BPAF) found in plastics, phthalates (e.g., DBP, DEP) used to produce soft plastics and to carry fragrances in cosmetics, parabens used as preservatives in cosmetics and cleaning products and per- and poly-fluoroalkyl substances (PFAS) used in cookware and furniture as protective coatings (2).  

Exposure to these chemicals can result in them entering your body. For example, bisphenols in packaging can get into your food which is subsequently swallowed (3). EDCs can affect how your hormones function, which is tightly controlled by the endocrine system. Some EDCs can mimic oestrogen; continuously high levels of oestrogen in your body is known to increase your breast cancer risk (1).   

Disruption caused by repeated low-level exposure to EDCs can potentially increase the levels of oestrogen, which encourages tumour growth in oestrogen receptor-positive breast cancer (4).  

Given these potentially serious effects, Breast Cancer UK adopts a precautionary approach to the use of endocrine disrupting chemicals. If there is scientific evidence that a particular chemical has possible links to breast cancer, we advise the general public to avoid it and call for its use to be restricted or banned to ensure that everyone is more protected.  

Why don’t all charities campaign on this issue?

Some charities are unfortunately not convinced that sufficient evidence is available to demonstrate harmful chemicals increase breast cancer risk. However, if organisations wait until all the evidence is available or until regulations are put in place restricting their use, it could be too late to reduce their damage to the planet as it will already be contaminated with harmful chemicals, resulting in continuous exposure for many more years.  

We believe there is enough evidence for a precautionary approach. By warning people now, we hope to raise awareness of the harmful effects associated with EDCs and reduce their overall adverse impact on our health and on the planet. 

Case study example: BPA has been subject to multiple restrictions 

This precautionary approach is particularly true for BPA, which has been subject to an increasing number of restrictions in recent years. BPA is used commercially as a component in the manufacture of many plastic items, including drinks bottles, food containers and casings for electronics.  

It is also used to line the inside of cans. And was, for many years, found in thermal ink used in paper receipts. The ubiquitous use of BPA meant that the potential for daily low-level human exposure was high (5).  

Although Breast Cancer UK has been calling for a ban on BPA use in everyday products since well before restrictions were imposed. Concerns started to be raised in 2008 as studies demonstrated BPA could promote adverse effects, including increasing the growth of breast cancer cells. Many more in vitro (using cell culture) and animal studies* followed, which showed continuous exposure to BPA in the normal breast, can promote characteristics of ductal carcinoma in situ (an early, non-invasive form of breast cancer that can lead to full; invasive breast cancer) (6). 

BPA now

This led to a cascade of restrictions for BPA, starting with a ban on infant feeding bottles in 2011 (7) and a restriction on its use in children’s toys three years later (8). 2017 saw BPA marked as a substance of very high concern (SVHC) due to its endocrine disrupting properties for humans and wildlife, in addition to its reproductive toxicity (9). More recently, in 2020, BPA use was restricted in till receipts (10).  

Today, many scientists and scientific organisations consider that long-term exposure to low levels of BPA promotes adverse effects on human health, including influencing the risk of breast cancer (4, 11, 12) 

BPA is a prominent example of why we do what we do. But we hope there is more to come regarding the restriction of other harmful chemicals. There is a clear need for better chemical regulation in the UK, something we are actively campaigning for alongside banning currently known EDCs in everyday products.  

BCUK is working to increase people’s awareness of all breast cancer risk factors 

Whilst we are avid supporters of other charities and the valuable work they do, the above example demonstrates that we are not alone in our concerns. That exposure to these compounds affects human health. Warnings from reputable scientists, international charities and organisations such as the United Nations Environment Programme, World Health Organisation (WHO) and the Endocrine Society suggest that EDC exposure, particularly to multiple compounds throughout our life, does have implications for human health, including increasing the risk of breast cancer (4, 11–14) 

We aim to increase awareness of all risk factors for breast cancer. But we hope that by funding more research into the effects of these chemicals regarding breast cancer risk and campaigning for a better strategy for the regulation and restriction of chemicals, we will raise more awareness of the lesser-known risk factors for breast cancer.  

This will help us to provide information and tips on how individuals can reduce their breast cancer risk. We strongly encourage other organisations to rethink their messaging regarding harmful chemicals and breast cancer risk.  

*Breast Cancer UK does not support research projects which involve animal experiments or materials derived from animal experiments.

For more information on how to reduce your risk of breast cancer, visit our Prevention Hub and take our Online Quiz to start your prevention journey.  

References 

1. Diamanti-Kandarakis E et al. 2009. Endocrine-disrupting chemicals: an Endocrine Society scientific statement. Endocrine reviews. 30(4): 293–342. https://academic.oup.com/edrv/article/30/4/293/2355049  
2. BCUK Background Briefing | Endocrine Disrupting Chemicals. 2018. Breast Cancer UK. https://cdn.breastcanceruk.org.uk/uploads/2019/08/BCUK_EDC_brief_v2_20.9.18.pdf (Accessed October 20, 2022). 
3. Scientific Opinion on the risks to public health related to the presence of bisphenol A (BPA) in foodstuffs. 2015. EFSA Journal. 13(1): 3978. https://www.efsa.europa.eu/en/efsajournal/pub/3978  
4. Gore AC et al. 2015. EDC-2: The Endocrine Society’s Second Scientific Statement on Endocrine-Disrupting Chemicals. Endocrine reviews. 36(6): 1–150. https://academic.oup.com/edrv/article/36/6/E1/2354691 
5. BCUK Background Briefing | Bisphenols and breast cancer. 2022. Breast cancer UK. https://cdn.breastcanceruk.org.uk/uploads/2022/11/BCUK_-Bisphenols-and-breast-cancer.pdf  (Accessed November 11, 2022). 
6. Wang Z et al. 2017. Low‐Dose Bisphenol A Exposure: A Seemingly Instigating Carcinogenic Effect on Breast Cancer. Advanced Science. 4(2): 1600248. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5323866/  
7. Commission Implementing Regulation (EU) No 321/2011 of 1 April 2011 amending Regulation (EU) No 10/2011 as regards the restriction of use of Bisphenol A in plastic infant feeding bottles. 2011. Official Journal of the European Union. https://www.legislation.gov.uk/eur/2011/321 
8. Commission Directive 2014/81/EU of 23 June 2014 amending Appendix C of Annex II to Directive 2009/48/EC of the European Parliament and of the Council on the safety of toys, as regards bisphenol A. 2014. Official Journal of the European Union. https://eur-lex.europa.eu/legal-content/EN/TXT/PDF/?uri=CELEX:32014L0081&from=ET 
9. Candidate List of substances of very high concern for Authorisation. ECHA. https://echa.europa.eu/candidate-list-table. (Accessed August 05, 2022). 
10. EU. 2016. Commission Regulation (EU) 2016/2235 of 12 December 2016 amending Annex XVII to Regulation (EC) No 1907/2006 of the European Parliament and of the Council concerning the Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) as regards bisphenol A (Text with EEA relevance). Journal of the European Union. L337: 3–5 https://www.legislation.gov.uk/eur/2016/2235/contents 
11. World Health Organisation, United Nations Environment Programme. 2012. State of the Science of Endocrine Disrupting Chemicals 2012 Summary for Decision-Makers. Inter-Organisation Programme For the Sound Management of Chemicals. https://apps.who.int/iris/handle/10665/78102. (Accessed October 20, 2022). 
12. Global Chemicals Outlook II: From Legacies to Innovative Solutions. 2019. UN Environment Programme. https://www.unep.org/resources/report/global-chemicals-outlook-ii-legacies-innovative-solutions (Accessed October 20, 2022). 
13. Soil Association, Pesticide Action Network UK. 2019. How Pesticide Mixtures may be harming human health and the environment. The Cocktail Effect. https://www.soilassociation.org/causes-campaigns/reducing-pesticides/the-pesticide-cocktail-effect/ (Accessed October 21, 2022). 
14. CHEMICAL COCKTAILS The neglected threat of toxic mixtures and how to fix it. 2022. ChemTrust. https://chemtrust.org/wp-content/uploads/Chemical-cocktails_CHEMTrust-report_March-2022.pdf (Accessed October 21, 2022). 

• awareness
• BCUK
• BPA
• Breast cancer
• breast cancer prevention
• Breast Cancer UK
• cancer
• charities
• edcs
• Harmful chemicals
• plastics
• reduce your risk
• science