RES – Lecture in Belgium on ending the breast cancer epidemic and Breast cancer book review
André Cicolella, President of Réseau Environnement Santé (RES), will present his new book “Cancer du Sein: En finir avec l’epidemie” (Breast Cancer, Ending the epidemic) 8 pm on Tuesday, 29 November 2016 in Louvain-la-Neuve, Belgium.
The book, which was published earlier this month, argues that the soaring incidence of breast cancer over the past 50 years is all about “bad” development – that is, the massive growth in synthetic chemicals used in food and everyday products in industrialised societies. It says that Belgium has the highest incidence of breast cancer in the world. More information on the new book available here.
More information and details of registration are available from "Au Sein des Femmes", the group which organised the event in partnership with the Sustainable Development House, Nature and Progress and the association Tournesol.
Book Review - Ending the breast cancer epidemic
This is a review of “Cancer du sein: En finir avec l’epidemie” published in October 2016 to coincide with “Pink October” in France. The book aims to answer the questions on the causes of breast cancer and to present a strategy for tackling the current epidemic.
“Cancer du sein: En finir avec l’epidemie” argues that the very high current incidence in breast cancer is not inevitable. The tide can be turned on this global problem. Breast cancer incidence has doubled between 1975 and 2000 resulting in the condition becoming the number one cancer for 90% of women worldwide.
An environmental disease
The author says: “The epidemic is not inevitable because it is primarily an environmental illness – that is to say, largely created by human activity. It is therefore possible to stop the epidemic if we can understand the causes.”
The book draws on five main sources of evidence: “All of which converge on the fact that the breast cancer epidemic can be significantly resisted through action on identified risk factors.”
They are: “Breast Cancer and the Environment. Prioritizing Prevention”, US Interagency Breast Cancer and Environmental Research Coordinating Committee (IBCERCC), February 2013; two reports from the US Breast Cancer Fund (BCF) - “State of the Evidence: The Connection between Breast Cancer and the Environment. From Science to Action,” 6th Edition, 2010 and “Working Women and Breast Cancer. The State of the Evidence” August 2015; a 2010 report on breast cancer by the World Cancer Research Fund and Breast Cancer Fund (BCF); and, research syntheses from the Silent Spring Institute.
He provides figures on the disparities in incidence and mortality rates around the world and calls for more studies on why such wide disparities exist.
“The disparities between countries show that it is possible to considerably reduce breast cancer incidence provided that its major causes are identified.”
The highest incidence is in Belgium (111.9 per 100,000 women) and the lowest in Bhutan (4.6 per 100,000 women). Closing this gap would prevent thousands of cases of breast cancer.
The difference between these two countries are both geographic and economic. Belgium is flat and Bhutan is mountainous and Belgium is considerably wealthier than Bhutan. However, Bhutan is not a poor country since it has a GDP similar to that of Lebanon. But Bhutan is somewhat unique.
“Bhutan has never had an industrial revolution and little in the way of the green revolution”.
The suggestion here is that the type of development path a country takes may play a role.
However, many other arguments are given as to why breast cancer is likely to be primarily an environmental disease.
“A study of registries of twins in three Nordic countries (Denmark, Finland and Sweden) … allowed a calculation of the role of hereditary and environmental factors in different diseases… For breast cancer, it appeared that the environment was responsible for 73%.”
“Studies show that within a few years of moving to another country, migrants have the same incidence rate as the host country.”
Genetics plays a role but the main risk of genetic mutation is associated with BRCA1 and BRCA2 genes, which only 3-10% of the population carry. Nor can genetics fully explain the rapid upward trend in breast cancer incidence because the increase has taken place in too short a period of time.
An aging population plays a role in the increasing incidence but a Norwegian study shows that incidence rates are increasing in younger and older women, including the 40 to 49 years’ age group. In France, the incidence of breast cancer is increasing in women under 40 years.
National breast cancer screening programmes affect the figures during their introduction but this reaches a peak and then the figures fall back to previous trends.
Latest scientific thinking
Three current strands in scientific enquiry are challenging understanding of how cancer is triggered.
“The most fundamental assumptions related to cancer are in the process of evolving considerably.”
The idea that aging is a major cause of cancer rests on the assumption that the origin of a cancer is a genetic mutation. Thus, the older we get, the greater the risk. Such “reductionist” thinking was challenged in 2000 by an important scientific article proposing six different biological mechanisms involved in carcinogenesis (formation of cancer), including endocrine disruption. In a subsequent paper, the number of major mechanisms was later increased to 11. By 2015, the work of about 200 scientists in the Halifax project, named after the Canadian city where their first meeting was held, led to the publication of a series of articles on each of these 11 major mechanisms.
“The conclusion reached, from the point of view of prevention, is that the chemicals implicated in these different mechanisms should be considered as carcinogens, even if they do not induce mutation.”
“The reasoning goes beyond chemical exposure to disruption by other factors. To be effective therefore, prevention must adopt a wide vision of what constitutes environmental factors.”
In a second strand of evolving scientific thinking, the concept of endocrine disruption was coined in 1991. It challenges the basic principle of toxicology that “The dose makes the poison”. According to this vision:
• Age at which the exposure takes place affects the impact a chemical can have
• The time between exposure and effects can be lengthy (and complicate identification)
• The “cocktail” effect – substances that would not individually have an effect at a particular level may induce an effect as part of a mixture
• The relationship between dose and effect – a low dose may produce a stronger effect than a high one
• Transgenerational effects – an exposure in the womb can be transmitted to the next and several subsequent generations. This has been shown in children of women exposed to DDT or who took the medication, Diethylstilbestrol (DES) during pregnancy to prevent miscarriage. Animal studies have shown its effects can extend to grandchildren and great grandchildren.
A third new strand in scientific thinking offers further insights on endocrine disruption and breast cancer. Since 1989, the “Developmental Origins of Health and Disease” or Dohad concept, has challenged Darwin’s theory that evolution takes place slowly by mutations in the genome itself while “… the concept of the developmental origin allows an evolution, a rapid adaptation, in one generation, and which can bring about changes in the DNA solely as a result of epigenetic markers.”
In 2012, scientists published “Environmental stressors in the development origins of disease. Evidence and mechanisms”, which concluded that many major conditions, including obesity, diabetes, hypertension, cardiovascular diseases, asthma and allergies, immune and auto-immune diseases, neuro-development and neuro-degenerative illnesses, early puberty and infertility, certain types of cancer, osteoporosis, depression and others may all be linked to factors in fetal and early postnatal development. Several of these conditions, such as obesity and early puberty, are also risk factors for breast cancer.
All three strands in this new scientific thinking point to the likelihood that environmental factors are key to breast cancer prevention.
“The positive conclusion is that there is no inevitability and that it is possible to turn the tide on the breast cancer epidemic, amongst others.”
A wide definition of “environment” is taken to understand the reasons for the epidemic.
“The environmental causes of breast cancer are multiple: chemicals, synthetic hormones, lifestyle, lack of exercise, etc. and most commonly these factors interact.”
Although the focus is on the role of endocrine disrupting chemicals, special attention is also given to radiation, work conditions, night work, and the combined effect of many different causes.
Exposure to natural and synthetic hormones are known to increase the risk of breast cancer.
It is known that the length of time to which a woman is exposed to her own hormones affects her risk of developing breast cancer. Early puberty and/or late menarche are both significant risk factors. Pregnancy and breastfeeding can play a protective role.
Exposure to synthetic hormones in the contraceptive pill or HRT can also increase the risk for some women.
“IARC has classified oral contraception before the age of 20 years as carcinogenic.”
“The fall (in breast cancer incidence in France) since 2005… is generally attributed to the gradual drop is use of hormone replacement therapy around the time of menopause.”
Other chemicals to which women are exposed may also play a role. The Silent Spring institute has identified 216 chemicals that can induce mammary tumours in mice and rats. From this work, the US Breast Cancer Fund has defined a list of chemicals that should be prioritised for removal from the market.
“Certain chemicals with mutagenic properties and/or identified as endocrine disrupters …induce mammary tumours in animals, primarily after maternal exposure in the womb.”
It seems probable that exposure of the mother can affect her child in the womb. Evidence comes from the DDT story. One important study cited shows a higher risk of breast cancer among three groups of women: those who were exposed to higher levels of DDT, those exposed during puberty, and daughters exposed during pregnancy.
In studies on rodents, bisphenol A (BPA) is responsible for mammary tumours. BPA, which is an example of a typical and widely prevalent endocrine disruptor, is similar to the banned medicine, DES. Given that the daughters of pregnant mothers who took this drug are at greater risk of breast cancer, it seems likely that BPA can induce breast cancer in human beings.
Moving to end the epidemic
The author concludes that the studies of Barbara Cohn on the effect of DDT on mothers and daughters (mentioned earlier) offer convincing evidence that chemical contamination, especially by endocrine disruptors, represents a determinant factor in breast cancer.
This chemical contamination has effects both in terms of direct exposure, such as from DDT and BPA, and indirectly by contributing to factors that increase breast cancer risks, such as early puberty and obesity. The latest science shows that it is vital to minimise contamination from the moment of conception because this period affects adult health. The aim is therefore to create a world in which babies are not born “pre-polluted”.
“The principle of zero contamination of the new born should be the alpha and omega of any environmental health policy.”
The first target is the eradication of BPA – in a programme that could be compared to that of the successful eradication of smallpox.
This needs to be complemented with action to eliminate or reduce the impact of the main chemicals associated with breast cancer. In order that the policy helps prevent a wider group of conditions that are partly chemical in origin, the author points to the two lists that include the chemicals of greatest concern for health from exposure to endocrine disruptors: The “SIN List” and the list developed by TEDX – The Endocrine Disruption Exchange.
In particular, the author calls upon France to show global leadership on this issue by building on the pioneering role it has already played, for example, in being the first to ban BPA in baby bottles.
Other recommendations include:
1. Taking environmental health to the UN Assembly in the context of addressing “non-communicable diseases” (NCDs). The causes of breast cancer are similar to those of other chronic conditions.
2. Supporting cancer plans that include a strong environmental health component.
3. Developing research, especially on the disparities in breast cancer between countries.
4. Rethinking professional and citizens’ education and training on environmental risks, including endocrine disruption.
5. Strengthening maternal and child health services and school and work health programmes.
Andre Cicolella is a chemical toxicologist, a former scientific adviser at France’s national research institute on environmental risks and a university lecturer on health and environment in Paris. He heads the association Réseau Environnement Santé, which started the action that led to a ban on bisphenol A in baby bottles and on perchloroethylenes used in dry cleaning in France. “Cancer du sein: En finir avec l’epidemie” is published by Les Petits Matins.
Last updated on 19 December 2016