Breast Cancer and PesticidesYour chances Pesticides that mimic estrogen areThe Canadian Cancer Society estimates that bad newscurrently one in nine females has a lifetime risk But isn’t estrogen a good thing for women?of being diagnosed with breast cancer. Male While it is essential for female reproductivebreast cancer is very rare at one percent of all functions, it can trigger and or feed some typescancers in males (1). of breast cancers.Are more diagnoses being made mainly Like cholesterol, ‘good’ and ‘bad’ estrogensbecause of better detection methods? Possibly, are manufactured by the body. ‘ Good-but the steady rise of breast cancer cases since estrogen’-production can be stimulated bythe 1940s pre-dates mammography, so better eating foods such as soya beans and broccoli,detection does not explain why breast cancer that break down quickly in the body and seemhas become so common (2). to protect against breast cancer. ‘Bad-estrogen’-production can be stimulated by synthetic estrogens in birth-control pills andCauses and risk factors estrogen replacement therapies, and also by theOnly about five percent of breast cancer cases presence of some estrogen-mimickingin females is passed on by the breast cancer organochlorine pesticides, plastics and bondinggene (2). Other causes are more difficult to agents in detergents and paints (2).predict and to prove. Exposures to high doses Pesticides are commonly found in our food,of chest X-rays, alcohol and tobacco use are all indoor and outdoor air, drinking water, and ofrecognized risk factors. Organochlorine course in insect repellants applied to our skinpesticides and other environmental toxics are (3) (4). Some do not break down easily in thehighly suspect as further possible causes. environment, and can accumulate up the foodTiming of events in one’s reproductive history chain where they are stored in our fat.is also tied to the likelihood of developingbreast cancer, and so this can be considered tobe a risk factor. Timing of such events asbirths and age at menopause also gives anindication of lifetime exposure to estrogen,another possible cause of breast cancer (2).
Reducing the chances of breast cancerSadly, an effective way to rid our breast fat ofpesticides suspected of causing breast cancer isto breast-feed (5) (6), but now breast milk hasbecome the most contaminated of all humanfoods (5).So should women still breast-feed? Generally,yes! Women who have breast-fed tend to haveless breast cancer, likely and at least partiallybecause of the downloading of toxics,including pesticides. Nevertheless their babiesstill tend to be healthier than their formula-fed Referencespeers (5) (6). Unfortunately, though, the milkof some women, especially those in the high (1) Canadian Cancer Society Information ServiceArctic, has become quite seriously statistics 1999. Call 1-888-939-3333contaminated (7). (2) Davis, DL and Bradow, HL: Can Environmental Estrogens Cause Breast Cancer?, Scientific American, October 1995How can women minimize exposure topesticides? (3) Pesticides and Human Health, Environmental Health Committee Newsletter, The Ontario CollegeEat organically produced food, and don’t use of Family Physicians, 1998pesticides on your skin, in your homes or on http://www.cfpc.ca/ocpf/commun./pest.htmlyour gardens. There are alternatives that work, (4) Davies, K: Pesticides and Your Child: anand don’t forget that chemical pesticides are a overview of exposures and risks, CPR publication,relatively recent invention. Sierra Club of Canada, 1997Contact your municipal, provincial and federal (5) Steingraber, S, in Protecting Plublic Healthgovernment representatives and tell them you and the Environment: Implementing thewant immediate and effective protection from Precautionary Principle, Raffensperger, C andthe dangers of pesticides, and that all need to be Tickner,J, editors, Island Press, 1999, (alsore-evaluated for their bio-accumulative recommended: Steingraber, S: Living Downstream,potential as toxics now, not later. The federal Addison Wesley Publishing,1997)Commissioner for the Environment has warned (6) Land, P: Linkage of Breast Cancer andthat the federal government is not properly Pesticides through Lactation Studies; presented atprotecting us from the risks of these chemicals the Second World Breast Cancer Conference, July(8). 1999 and available through CPR, Sierra Club of Canada (7) Jensen, J et al, (eds): Canadian Arctic Contaminants Assessment Report, NorthernFor more information, contact: Contaminants Program, Indian and Northern Affairs Canada, 1997Pesticides Campaign Director, (8) Emmet, B, Commissioner of the Environment Sierra Club of Canada, and Sustainable Development’s Annual Report, 1 Nicholas Street, Suite 412, May 25, 1999, cited in Globe and Mail, May 26, Ottawa, Ont., 1999: Ottawa faulted on chemicals, pesticides: K1N 7B7, Canadians at risk, report charges. firstname.lastname@example.org.