Plastic Free July and breast cancer risk.

Every July, millions of people around the world take on the Plastic Free July challenge - swapping single-use plastic for reusable alternatives, like choosing wooden utensils over plastic.

Every July, millions of people around the world take on the Plastic Free July challenge - swapping single-use plastic for reusable alternatives, like choosing wooden utensils over plastic. The motivation is usually environmental, with plastic accounting for at least 85% of all marine waste. But there’s a health reason to join in too, one that doesn’t get nearly enough attention. 

A growing body of research has shown certain chemicals like Endocrine Disrupting Chemicals (EDCs) found in some plastics to disruption of the body’s hormone system. These chemicals have been identified in several human bodily fluids and tissues including blood, urine and breast milk and tissue. And since the majority of breast cancers are hormone-sensitive, that connection is one scientists and campaigners (like us here at Breast Cancer UK) are taking increasingly seriously. 

Here’s what you need to know about the link between plastic and breast cancer risk this Plastic Free July.  

What are EDCs? 

EDCs are substances that interfere with the way hormones such as oestrogen work in the body. They can mimic hormones, block their effects or alter the signals they send.  

EDC exposure has been linked to several health issues. Even at low levels, they may have significant effects, particularly during sensitive periods of development such as in the womb, early childhood, and during puberty. . 

Plastics are one of the most significant sources of EDC exposure, but they are also found in many other everyday products. The key chemicals to know about are: 

Due to the extensive use of EDCs in everyday products, exposure is widespread. EDCs can be released from products and enter our bodies through what we eat and drink, the air we breathe and through our skin.  

What is the endocrine system? 

The endocrine system is the network of glands and organs that produce hormones (the chemical messengers that travel through the bloodstream and allow different organs to communicate). The endocrine system underpins several important bodily functions, from development and metabolism to reproduction. Read more about the endocrine system here.

What does the research say about plastics, EDCs and breast cancer? 

EDCs have been linked to an increased breast cancer risk due to these chemicals being able to mimic the hormone oestrogen in the body, and having high levels of oestrogen is a risk factor for breast cancer. Some studies have indicated that exposure to EDCs may increase the risk of cancer, but more research is needed.  

However, the honest answer is that proving direct cause and effect in humans is difficult. Most laboratory and regulatory studies look at single chemicals, whereas real-world human exposure is far more complex. 

People are exposed to complex low-level mixtures of chemicals throughout life. The combined impact of multiple EDCs at once may be significantly greater than any individual chemical alone, this is known as a ‘cocktail effect’.  

The timing of exposure also matters. The same chemical may have different effects depending on whether exposure occurs during foetal development in the womb, puberty or adulthood. These effects may also take several years to manifest, making it difficult to track or pinpoint the exact cause. 

Despite these issues, evidence of EDCs affecting human health is Breast Cancer UK’s position is that the precautionary principle should apply. These chemicals should not remain in widespread use until they are proven safe. Waiting for certainty, given the scale of exposure and the potential consequences, is not a neutral choice. 

Why is public awareness so low? 

Our annual Prevention Week campaign ran in May under the theme EDCs: Hiding in Plain Sight. This highlighted the hidden chemicals in everyday products and called on the UK Government to act. 

Opinion polling commissioned by Breast Cancer UK in 2026 (Opinion Matters, 2000 surveyed, March 2026) also found: 

This isn't a failure of public interest. The problem is a failure of regulation. Since Brexit, the gap between UK and EU chemical regulation has been widening. Unlike the EU, which has introduced comprehensive bans on certain chemicals and formally recognises EDCs require labelling - the UK has been slow to act.  

Read our full campaign briefing for the complete evidence and policy detail. 

One swap, real impact for Plastic Free July. 

Plastic Free July gives us a timely, practical entry point. Cutting down on single-use plastic isn't just good for the oceans, it's a meaningful way to reduce EDC exposure in your daily life that could have a positive impact on your health. This July, we’re asking you to make a simple swap:  

Replace plastic cooking utensils with wooden or metal alternatives (they don't degrade at high temperatures and won't transfer chemicals into food) 

For a more comprehensive guide to reducing EDC exposure at home, download our free EDC home guide. You can also download our A-to-Z Chemicals of Concern list to help check product labels when out shopping. 

Every swap, every share brings us closer to a world where people don't have to choose between convenience and their health. 

What needs to change 

Breast Cancer UK is calling on the UK Government to ban EDCs in all non-essential products. This isn’t a fringe position; it simply reflects the direction that the EU has already started to take. 

These chemicals are embedded in the supply chains of so many products, making it increasingly difficult for people to inspect or avoid.  

Plastic Free July is a great way to build awareness and start reducing your own exposure. But the current scale of EDC exposure also requires a fundamental change in policy that will reduce exposure for everyone, including those who never hear about it. 

We campaign for the prevention of breast cancer through research, education and policy change. Are you with us?  

Sign the Ban EDCs pledge now. 

FAQs 

Is BPA-free plastic safe? 

Not necessarily. BPA-free products often contain alternative bisphenols (BPS, BPF and others) which appear to have similar hormonal activity but are currently unregulated. This is known as regrettable substitution.  ‘BPA-free’ should not be read as ‘EDC-free.’ 

Are the levels of EDCs in products too low to matter? 

This is a common argument from industry, but it may not hold. EDCs don't behave like most; low doses can have effects that high doses don't. They also accumulate in the body over time, and combined daily exposures (the cocktail effect) throughout life can exceed safe levels even when each individual chemical is present at low levels. 

What is the precautionary principle? 

The precautionary principle holds that where there is reasonable scientific evidence of harm, action should be taken to protect public health, even before absolute proof of causation has been established. It requires industry to demonstrate safety, rather than on regulators to prove harm. 

How does the UK compare to the EU on EDC regulation? 

The EU has taken a more precautionary, hazard-based approach to chemical regulation.  For example, banning bisphenols in food contact materials, formally recognising EDCs as a hazard class, and are currently considering a universal ban on all PFAS. Since Brexit, the UK has introduced fewer equivalent protections and is increasingly diverging from EU standards.

woman swimming in the sea