Do chemicals in plastics cause breast cancer?
Published 27 Jan 2015
I would have thought that the horrifying prospect that by 2020 half of us will face cancer at some point in our lives would bring cancer charities together in a unified determination to unearth the root causes of the disease. Sadly this was not evident in a blog statement issued by one breast cancer charity this week which in response to an article in the Telegraph felt compelled to state that “there is no convincing scientific evidence to back up claims that pesticides or chemicals found in plastics cause cancer in people”. This statement is as inaccurate as it is unhelpful, because it does not reflect the growing body of scientific evidence that suggests otherwise.
Naturally we were encouraged last week when the Telegraph gave some much needed air time to a question we have been asking for the last ten years (and scientists like Rachel Carson and Theo Colborn for decades): 'Could an increase in incidence rates of cancer be a result of the chemicals in our environment, food and drink?' In her article, Judith Potts, herself diagnosed with breast cancer, raised concerns about the increasing number of younger people being diagnosed with cancer and wondered whether scientists were looking in the right direction in their hunt for the cause of this disease.
Her article referred to our call for Bisphenol A (BPA) to be banned from food and drinks packaging because of concerns that it has been found to damage the developing mammary gland in a way which could increase the risk of breast cancer. These concerns are well founded and have been echoed by the European Commission which in 2010, banned BPA in babies bottles because of its possible “effect on development, immune response and tumour promotion”. More recently, the French Health Authority, ANSES, voiced concerns that BPA could lead to a “change in the structure of the mammary gland in the unborn child that could promote subsequent tumour development”, which led to a French ban on BPA in all food and drinks packaging which came into effect this month. These concerns are echoed by many scientists, health organisations and politicians across the globe that are worried that BPA is just one of many chemicals which either individually or in combination could be one of the reasons why rates of ill health, including cancers, are rising in the western world.
Yet a well-known breast cancer charity here in the UK disagrees. In its response, the possibility that chemicals in plastics, such as BPA, or pesticides, have any role to play whatsoever in the rising rates of cancers is soundly rebuffed as “clichéd” and “speculation”. It is a surprisingly unswerving and entrenched response, which not only ignores a lot of scientific evidence, but also betrays a fundamental misunderstanding of the sort of chemicals we are concerned about.
BPA is one of many hundreds – possibly thousands - of Endocrine Disrupting Chemicals (EDCs) used in products (like plastics and pesticides) that cause damage because they can interfere with normal hormone functions in humans and lead to cell changes or tissue damage which could increase the body’s vulnerability to cancers. In light of this, the self assured rebuff that BPA is not carcinogenic is not only misplaced but misleading. All too often those that wish to dispel “myths” that chemicals are not carcinogenic base their assumptions on the assumption that we know everything about how the body works, how tissues develop and how chemicals impact on developing tissues. Yet the simple truth is: we do not. To assume that, simply because a chemical has not been shown to be carcinogenic, it must be safe, is not only illogical but extremely dangerous. What this assumption misses is that chemicals can be harmful and exert their effects in different ways. With BPA, it is the chemical’s ability to mimic oestrogen and interfere with the normal development of the mammary gland that is of concern.
The fact is we know that synthetic oestrogens DO play a role in breast cancer risk (e.g. HRT, DES, the oral contraceptive) and several studies have linked prenatal BPA exposure to an increased incidence of mammary gland tumours. We think this should be enough to warrant concern, questions, further investigation and yes – precautionary action.
Rather than dismissing our concerns, a more measured response would perhaps have been to acknowledge that there is debate in this area, as well as a growing body of scientific data that poses key questions about the role that our exposures to chemicals like BPA are playing in the rising rate of cancers and other diseases. This uncertainty has led thousands of us to call on the European Union to introduce tougher regulations that would enable us to more accurately assess and categorise EDCs to help better protect public health.
We are pleased that some research is being undertaken by the cancer charity in question to study the environmental risk factors for cancer yet the statistics suggest that this area of research gets nowhere near as much attention as other areas. The fact is only 3.6% of cancer research funding went towards prevention in 2013 and only 1.2% on the 'exogenous' or environmental causes of the disease. In light of this woeful underfunding in to prevention, Judith Pott’s original question; “Could it be that doctors and researchers are looking away from what is around us” would seem apposite.
I do not dispute the good work that cancer charities in this country have done - or are doing - to identify the root causes of breast cancer. Yet prevention and the environmental causes of the disease remain an underexplored area of research that is in desperate need of further funding, certainly a great deal more understanding amongst mainstream cancer charities and definitely in need of more debate.
To reiterate, by 2020 almost half of Britons will get cancer in their lifetime. We should be working together to help put a stop that horrifying trend.
IPCS. (2002). Global assessment of the state-of-the-science of endocrine disruptors. Geneva, Switzerland, World Health Organization, International Programme on Chemical Safety.
Diamanti-Kandarakis E, et al., (2009). Endocrine- disrupting chemicals: an Endocrine Society scientific statement. Endocrine Reviews, 30(4): 293–342.
Soto AM, et al., (2013). Does cancer start in the womb? altered mammary gland development and predisposition to breast cancer due to in utero exposure to endocrine disruptors. Journal of Mammary Gland Biology Neoplasia 18(2): 199-208.
UNEP/WHO (2013). State of the science of endocrine disrupting chemicals 2012
TEDX. Endocrine Disruption