How might harmful chemicals affect the health of my baby?
It is important to stress that, whilst the data on hormone disrupting chemicals is a long way from being conclusive, there is a great deal of evidence showing that early life exposures to certain harmful chemicals could lead to an increased vulnerability to ill health later in life (1).
We already know that early exposures to well-known chemicals, such as those in cigarette smoke, can have immediate and long term detrimental health effects, including reduced birth weight, childhood obesity, congenital heart defects and a predisposition to kidney, cardiovascular and gastrointestinal disease in later life (2).
In addition, evidence suggests that exposure to other chemicals that disrupt our hormones during early development may also increase the risk of endocrine-related diseases in later life such as endometriosis, hypospadias (abnormal urethra development) and reproductive cancers, including prostate and breast cancer (3, 4, 5).
Harmful chemicals and breast cancer
The female sex hormone, oestrogen, is known to be an important factor in breast cancer risk (6). Hormone disrupting chemicals which mimic oestrogen could cross the placenta and affect the developing mammary gland (7).
For example some research suggests pregnancy exposures to certain hormone disrupting chemicals including bisphenol A, widely used in plastics manufacture and found in numerous products including food can linings, may cause changes in the development of the mammary gland which could increase the risk of breast cancer later in life (8, 9, 10). Similarly, another study indicates that pregnancy exposure to butyl benzyl phthalate, used to soften plastics, induces mammary gland changes associated with increased breast cancer risk (11).
Whilst it is very difficult to prove conclusively that exposure to certain chemicals in the womb or during childhood causes ill health and breast cancers later in life, current research indicates that it is wise to take caution.
1. WHO (2012). Endocrine disrupters and child health. Possible developmental early effects of endocrine disrupters on child health. Geneva; World Health Organisation: 2012 Accessed February 6 2015
2. Mund, M. et al. (2013). Smoking and Pregnancy — A Review on the First Major Environmental Risk Factor of the Unborn. International Journal of Environmental Research and Public Health 10(12): 6485–6499
3. UNEP/WHO (2013). State of the science of endocrine disrupting chemicals 2012. Accessed February 5 2015
4. Diamanti-Kandarakis E., et al. (2009). Endocrine- disrupting chemicals: an Endocrine Society scientific statement. Endocrine Reviews, 30(4): 293–342.
5. Gibson, D.A. and Saunders, P.T.K. (2014). Endocrine disruption and reproductive cancers. Endocrine-Related Cancer 21: T13–T31.
6. Travis, R.C. and Key, T.J. (2003). Oestrogen exposure and breast cancer risk. Breast Cancer Research 5: 239-247.
7. Jenkins S, et al. (2012). Endocrine-active chemicals in mammary cancer causation and prevention. Journal of Steroid Biochemistry and Molecular Biology 129: 191-200.
8. Jenkins S, et al. (2012). ibid
9. Vaiserman, A. (2014). Early-life Exposure to Endocrine Disrupting Chemicals and Later-life Health Outcomes: An Epigenetic Bridge? Aging and disease 5(6): 419-429.
10. Soto, A.M. 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.
11. Moral R et al. (2011). In utero exposure to butyl benzyl phthalate induces modifications in the morphology and the gene expression profile of the mammary gland: an experimental study in rats. Environmental Health 10(1): 5.