Hormones in our environment
There is some public concern about the effect of certain chemicals in our food, environment and household goods. But the evidence linking these chemicals to cancer has generally been poor or inconsistent.
Concerns have focused on a group of chemicals that could mimic or change the effects of human hormones, like oestrogen. This group of chemicals has several names including ‘hormone disrupting chemicals’ and ‘endocrine-disrupting chemicals’ (EDCs).
What are EDCs?
EDCs are a large group of chemicals and can be found in things like plastics, pesticides and solvents. So we could be exposed to them in a variety of ways, including eating or drinking affected food or water. The worry is that EDCs could disrupt the action of hormones in our bodies, leading to health problems, including cancer.
Can EDCs Cause Cancer?
Some people suggest that the increasingly common use of EDCs explains why some types of cancer have become much more common in the last century. But there is no good direct evidence to support this. Although the number of cancer cases is set to keep rising, there are other reasons for this. One of the most important is the fact that people are living longer than they used to, and cancer is more common among older people.
We know that our own hormones are linked to the development of some cancers, including breast and endometrial cancer (a type of womb cancer). But at the moment scientists don’t fully understand what goes wrong in the body to allow our own hormones to cause cancer. Without understanding this, it’s hard to say if and how EDCs could cause cancer.
Studies with animals and cells have shown that EDCs can disrupt hormone interactions and cause cancer in the laboratory. So it is possible that EDCs could cause cancer in people, but we don’t know for sure.
To get a clear answer, scientists need to do large, carefully-designed studies looking at people and their exposure to environmental chemicals. This is because there are still many types of chemicals that have not been studied enough, and we also need to know more about whether the combination of chemicals is important. And even if studies find that certain chemicals can cause cancer in particular situations, there might not be a risk to the public if people are only exposed to a small amount of these chemicals. At the moment there is no strong evidence that EDCs at current levels cause cancer in people in the UK, but we can’t rule this out either.
Types of EDCs
There are a large number of different EDCs that are sometimes mentioned in the news. Some of the most commonly talked about chemicals are described below.
Bisphenol A (BPA)
BPA is a chemical found in plastic. There has previously been concern that BPA in plastic bottles and food containers causes cancer, but there is currently no good scientific evidence to suggest that this is the case. To find out more about BPA, visit our plastic bottles and food containers webpage.
Dioxins and PCBs
Dioxins are released in some industrial processes. Although some types of dioxins may cause cancer if people are exposed to too much, their levels are regulated in the UK and are much lower than in previous decades.
Pesticides are chemicals used in agriculture. Some of these chemicals have been found to cause cancer in animals at high doses, but the levels found in foods are tightly regulated to make sure they do not pose a risk to human health. Fruit and vegetables sometimes contain very small amounts of pesticides. But there is no convincing evidence that these small amounts increase the risk of cancer in people who eat them. And fruit and vegetables are an important part of a healthy diet. You can read more about pesticides on our food controversies webpages.
Phthalates are a group of chemicals that can be found in some plastics, cosmetics and personal care products. There is no good evidence to suggest that phthalates cause cancer in humans17.
Triclosan is a chemical found in toothpaste, cosmetics and cleaning products. There is no good evidence to suggest that triclosan causes cancer.
How can I reduce cancer risk?
We need to know more about EDCs and cancer in people, but in the meantime it’s important to remember that there are a number of things that we already know about that can reduce our risk of cancer. More than 4 in 10 cancer cases could be prevented through making changes like stopping smoking, keeping a healthy weight and reducing the amount of alcohol we drink.