Endocrine disruptors

So, you’ve heard about endocrine disruptors and are wondering if these substances are going to hurt you or harm the environment. We have the full story on what they are, what they do (and don’t do!), and why it’s not as bad as you might fear.

The endocrine system is the body’s network of glands that produces hormones. These hormones control almost every aspect of how our body works, from sex to sleep to our emotional state, and there are many ways in which they can be influenced for good and bad.

What are endocrine disruptors?

‘Endocrine disruptor’ is a term originally used to refer to certain substances that were found to cause harmful effects in some species of wildlife by interfering with the functioning of their hormones.Hormones are naturally-occurring substances produced in the body as part of the ‘endocrine’ system. They act as chemical messengers which help control a wide range of processes ranging from reproduction to immunity, metabolism and behaviour. 

Can they harm you or your family?

The endocrine system helps control so many aspects of human function and development, so it’s easy to think of ways in which ‘disruption’ of that system might have harmful effects.

There are also trends which suggest more people suffer from conditions ranging from allergies to obesity and reproductive problems to breast cancer. Scientists around the world are looking for explanations and factors contributing to these trends. 

Very little evidence of harm

It has been suggested that, theoretically at least, these conditions might result from malfunctioning of the endocrine system. However, while it is important that all possibilities should be considered, there are many other possible explanations for these trends.

To date, other than for some specific industrial exposures, no evidence has been found to show that people are being harmfully affected by exposure to ‘endocrine disruptors’.

Dangerous substances would be prohibited

Substances that are shown to be capable of causing cancer in humans or harming reproductive health, given a high enough dose, would be prohibited by law from use in cleaning products.

Do I need to worry about a total dose?

No. While it’s true that doses of different substances that work in exactly the same way can sometimes add up, different substances being described as ‘endocrine disruptors’ have different ways of interacting with the endocrine system. Some would actually have directly opposite effects. 

For example, some mimic particular hormones, while others block the action of the same hormones so they’d cancel each other out. In any case, the potential effects of many ‘endocrine disruptors’ would be completely swamped by all the naturally occurring substances we are constantly exposed to, whether those are naturally produced hormones or phytoestrogens in our food for example.

Can they harm animals?

The first noticed effects of endocrine disruptors included changed sexual characteristics in alligators, which were affected by persistent pesticides in lakes polluted with waste. These pesticides have now been banned.

In the UK, feminisation of fish has been seen in rivers near sewage works, mainly due to natural female hormones and the contraceptive pill in the sewage effluent.

Are they in cleaning products?

Substances that have been shown to harm people or wildlife by interfering with hormone function are not used in cleaning products, and would be banned from use by law.

EU has strict controls

More than ten years ago the EU produced a list of over 550 substances suggested by various groups to be investigated as being potential ‘endocrine disruptors’. Many of these are pesticides which have long since banned. 

None of the substances for which there is evidence of ‘endocrine disruption’ in living organisms are used in your cleaning products.

Some reports describe products incorrectly

Sometimes, you may see statements naming chemicals such as phthalates, parabens, triclosan or alkylphenol ethoxylates for example, saying that they are “endocrine disruptors” and are used in cleaning products. 

These statements are untrue, either because the ingredient concerned is not shown to be an endocrine disruptor or because they are not used in UK cleaning products.

How do I identify them?

This is the key question that scientists are trying to answer at the moment. The trouble is that it’s easy to find all kinds of things that can be shown, using different tests, to interact in some way with hormones, the glands that produce them, or the receptors the hormones connect with. 

These tests often provide valuable information on how different substances can interact with the endocrine system, they do not always show there will be an effect on people or that it will lead to harm.

Common food and drink 

Cabbage, soya beans, sprouts and even beer and wine are just some of the many foods that contain ‘phyto-oestrogens’, which tests show can mimic or inhibit the natural female hormone oestrogen. But there’s no evidence at all that people who consume these are being feminized or suffering unwanted effects that might be related to interference with the endocrine system.

Contraceptive pill

Then there’s the contraceptive pill: the active ingredient is specifically designed to alter the normal reproductive cycle in women by temporarily interfering with hormone action, and would be rated as a highly potent ‘endocrine disruptor’. 

But its effects on the hormone system are intentional and beneficial and there’s no evidence that it’s causing other endocrine related diseases or harmful effects.

Can they really cause harm?

More and more substances are currently being branded as ‘endocrine disrupters’ by campaign groups based on isolated tests. Often these show weak interactions that are thousands or millions of times less powerful than natural female hormones or the ‘pill’. 

So it’s important to ask ‘what evidence is there that this substance, in the amounts I’m likely to be exposed to it, is capable of causing harm’?

EU debate on definitions

There’s currently a debate at EU level about what regulations might be needed, and already some EU laws prohibit ‘endocrine disruptors’ from being used in certain fields. 

The UK is rightly insisting that there must be clear evidence of the ability to cause harm in a whole organism (i.e. not just cells in test tubes), as defined by the World Health Organisation (WHO), before a substance is formally classified as a potential ‘endocrine disruptor’, which could automatically result in it being restricted or banned.

Contact the UKCPI on ukcpi@ukcpi.org or call 07843 199397.