Breast Cancer and the Environment in the 21st Century


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Dr. Davis' presentation from Kingston, NY on the environmental causes of breast cancer, one of which is improper cell phone use.

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Breast Cancer and the Environment in the 21st Century

  1. 1. Breast Cancer and the Environment in the 21 st Century Devra Lee Davis PhD MPH Founder Environmental Health Trust Breast Cancer Options October 3, 2010
  2. 2. Available Evidence for Understanding Causes of Cancer Human studies cannot always be conducted. Models and measurements of exposure along with toxicology & case studies fill knowledge gaps. Toxicology Wildlife & Case Studies Human Studies
  3. 3. Toxicologic Evidence on Causes of Cancer
  4. 4. Breast cancer biology Clavicle Ribs Pectoralis (chest) muscle Breast tissue: Lobules Duct Connective tissue FAT Duct opening Nipple Sebaceous gland Inframammary fold Dr. Susan Love’s Breast Book
  5. 5. Stages of tumor progression Do not depend on whether or not tumors first arose from hormonal stimulation or from genetic damage
  6. 6. How does cancer occur? Initiated cell Invasive Tumor
  7. 7. Unlocking breast cancer “ Bad” estrogens ‘ unbound’ “ Good” estrogens ‘ bound’ Antioxidants Reductants Less Cell Proliferation Estrogen Receptors Cancer DNA Repair Damage
  8. 8. Animal Carcinogens Cause Cancer in humans <ul><li>Every compound known to cause cancer in humans </li></ul><ul><li>Also causes it in animals, when adequately studied. </li></ul><ul><li>Therefore any animal carcinogen should be treated as a human carcinogen* </li></ul><ul><li>*IBM Think Magazine, 1983 </li></ul>
  9. 9. Mammary Carcinogens in Tobacco Smoke & Engine Exhaust Aromatic hydrocarbons Benzene Benzo[a]pyrene Dibenz[a,h]anthracene Dibenzo[a,e]pyrene     Nitrosamines N-nitrosodiethylamine N-Nitrosodi- n -butyl-amine Aliphatic compounds Acrylamide Acrylonitrile 1,3-Butadiene Isoprene Nitromethane Propylene oxide Urethane Vinyl chloride   Arylamines and nitrarenes 4-Aminobiphenyl Nitrobenzene Ortho -Toluidine
  10. 10. Human Studies <ul><li>Trends in rates over time </li></ul><ul><ul><li>Racial and ethnic differences </li></ul></ul><ul><ul><li>Patterns of different age groups </li></ul></ul><ul><ul><li>Studies in twins </li></ul></ul><ul><li>Case comparison/control studies of risk factors </li></ul><ul><li>Geographic patterns </li></ul><ul><li>Studies in workers </li></ul>
  11. 11. Identical twins don’t have identical chromosomal banding patterns Chromosome 1 Chromosome 3 Chromosome 17 Chromosome 12 3 year old twins Fraga, Mario F. et al. (2005) Proc. Natl. Acad. Sci. USA 102, 10604-10609
  12. 12. As identical twins age, their chromosomes look less similar Chromosome 1 Chromosome 3 Chromosome 17 Chromosome 12 50 year old twins Photo:Maryellen Mark, Ned & Fred Mitchell
  13. 13. Environmental links to breast cancer –Scandinavian Twins Study <ul><li>Most cancer is not inherited </li></ul><ul><li>Evaluated inherited vs. environmental breast cancer risk factors </li></ul><ul><ul><li>Inherited factors, 27% of risk </li></ul></ul><ul><ul><li>Environmental factors, 73% of risk </li></ul></ul><ul><ul><li>Concluded that environmental factors play a major role in determining breast cancer risk </li></ul></ul><ul><ul><li>Ref: Lichtenstein et al., N. Engl. J. Med., 343:78-85, 2000 </li></ul></ul>
  14. 14. Reasons why “environment” is a cause of cancer <ul><li>Cancer risk of adopted children mirrors that of their adopted (NOT their biologic) parents </li></ul><ul><li>Fewer than half of identical twins get the same cancer </li></ul><ul><li>Migrants develop risks of their new countries </li></ul><ul><li>Workers have higher rates </li></ul><ul><li>Patterns remain unexplained </li></ul>
  15. 15. Fewer than 1 in 10 cases of breast cancer arises in women born with genetic defects National Cancer Institute Reasons why “environment” is a cause of cancer
  16. 16. Female Breast Cancer Incidence and Death Rates* by Race/Ethnicity, US 1998-2000 Age-adjusted rates per 100,000 Source: American Cancer Society, Surveillance Research, 2005
  17. 17. Breast Cancer Death Rates in the Americas, 2000 Bosetti et al., 2005 Ecuador Colombia Mexico Costa Rica Brazil Chile Venezuela Puerto Rico Cuba USA Canada Argentina
  18. 18. Change in U.S. Breast Cancer Incidence 1975-79, 1990-94 500 400 300 200 100 0 40 50 60 70 80 Age (years) Incidence per 100,000 White 1990-94 1985-89 1980-84 1975-79 500 400 300 200 100 0 40 50 60 70 80 Age (years) Black 1990-94 1985-89 1980-84 1975-79
  19. 19. Personal Risk Factors for Breast Cancer Family HISTORY EARLY MENSES Use of HRT or LATE MENOPAUSE Early life RADIATION LACK OF EXERCISE/obesity ALCOHOL LATE OR NO PREGNANCY
  20. 20. Higher Total Lifetime Exposure to Unbound Steroid Hormones Binding Globulin (SHBG)  Is the Common Link Between Most Known Risk Factors
  21. 21. Environmental Risks for Breast Cancer Solvents Plastics Metals Pesticides Paints
  22. 22. Cumulative Risk of Breast Cancer in BRCA1 carriers born before or after 1940 (M. King, 2003) Cancer risk by age
  23. 23. Second Hand Smoke Increases Risk of Breast Cancer in Younger/but NOT older <ul><li>14 studies evaluated breast cancer risk in younger/premenopausal women strata. </li></ul><ul><ul><li>13/14 found elevated risks (1.1-7.1), and 7 were statistically significant. </li></ul></ul><ul><ul><li>Pooled risk estimate from meta-analysis = 1.68 (95% CI 1.31-2.15). </li></ul></ul><ul><ul><li>Pooled risk estimate for studies with lifetime exposure information from all sources = 2.2 (95% CI 1.69-2.87) </li></ul></ul><ul><li>Some evidence of dose-response. </li></ul>
  24. 24. Second Hand Smoke and Breast Cancer Risk
  25. 25. Studying Humans Is Difficult <ul><li>People seldom know what they have been exposed to </li></ul><ul><li>Breast cancer arises from prenatal, early-life and later-life exposures that cannot be easily measured at time of diagnosis </li></ul><ul><li>Studying current levels or recent residues in cancer patients can be misleading — disease development affects storage of toxic compounds </li></ul>
  26. 26. Could Air Pollution Increase Breast Cancer Risk? <ul><li>Air pollutants include numerous experimental carcinogens </li></ul><ul><li>Urban areas tend to have higher rates of breast cancer </li></ul><ul><li>Obtaining epidemiologic proof of any cause of a common disease is difficult </li></ul>
  27. 27. Premature sexual development* increased in African American girls <ul><li>Development of breasts or pubic hair occurred in </li></ul><ul><ul><li>1 out of 3 seven year old and 1 out of 2 eight year old black girls </li></ul></ul><ul><ul><li>1 out of 10 seven year old and 1 out of 8 eight year old white girls </li></ul></ul><ul><li>Reason for racial disparities unknown </li></ul><ul><li>Herman-Giddens et al., 1997 Pediatrics </li></ul>* adrenarche and thelarche
  28. 28. Twenty Two Month Old Girl with Breast Development
  29. 29. Plastic Metabolites in Girls w/wo Premature Breast Growth
  30. 30. How are we exposed to environmental chemicals? <ul><li>Routes of exposure </li></ul><ul><ul><li>Air we breath </li></ul></ul><ul><ul><li>Food we eat & beverages we drink </li></ul></ul><ul><ul><li>Contact with our skin </li></ul></ul><ul><ul><li>Contact with eyes </li></ul></ul><ul><ul><li>Some chemicals cross the placenta </li></ul></ul><ul><ul><li>Some can appear in breast milk </li></ul></ul>
  31. 31. Jobs with increased risk of breast cancer <ul><li>Solvent workers </li></ul><ul><li>Chemists </li></ul><ul><li>Nurses/Dentists </li></ul><ul><li>and Physicians </li></ul><ul><li>Painters </li></ul><ul><li>Hair Dressers </li></ul>
  32. 32. Epidemiologic Studies: Breast Cancer Risks from workplace studies * aromatic solvents, BTX Cantor, 1995 24 U.S. states death records 1984-89 29,397 cases white women 102,955 controls 1.19 (1.1-1.3) 1.19(.9-1.6) 1.10 (1.0-1.2) Formaldehyde Styrene Org. solvents Petralia, 1998 All Br CA cases in Shanghai 1980-84 14.7(5.9-30.3) 1.3 (1.1-1.8) Doctors Benzene workers Hansen, 1999 Danish workers 8,767 cases & controls 1.84 (1.15-2.95) 1.59 (1.13-2.24) 1.3 (1.1-1.4) Chem.workers 15+ years No lag All solvent workers*
  33. 33. Cadmium Exposure and Breast Cancer Risk Jane A. McElroy, et al, JNCI, June 21, 2006 <ul><li>Case-control study found that breast cancer cases had higher urinary levels of creatine-adjusted cadmium </li></ul><ul><li>OR = 2.29 95% (CI = 1.3 to 4.2) (p .01) </li></ul><ul><li>Women with the highest cadium in their urines had a doubled risk of breast cancer. </li></ul>
  34. 34. Dietary and Environmental Interactions <ul><li>Can diet protect against breast cancer progression by affecting interactions between estrogen and intracellular growth factor signaling pathways? </li></ul><ul><li>Hormones and growth factors act as chemical messengers in the body </li></ul><ul><li>Exogenous factors modulate: </li></ul><ul><ul><li>IGF-1 </li></ul></ul><ul><ul><li>ratio of 16-hydroxy-estrone) to 2-hydroxy-estrone ratio </li></ul></ul><ul><ul><li>inflammatory mediators </li></ul></ul><ul><ul><li>enzymes that detoxify reactive metabolites and steroid hormones </li></ul></ul>
  35. 35. 65 yo female presents with palpable and ma mm ographic finding patient grew up and lives in South Hampton, Long Island
  36. 36. 56 yo female presents with firm mass Chemist working with benzene for many years without a hood
  37. 39. Better Safe than Sorry …. Eat low on the food chain Reduce your fat Exercise daily Stop using toxic cleaning products Don’t drink heavily Avoid unnecessary x-rays Limit pesticide use Limit use of cordless cell phones Don’t keep cell phone in bra or on body Do NOT microwave or heat food in plastic
  38. 41. Truth is Stranger Than Fiction <ul><li>“ Gentlemen, practice these words in front of the mirror: Although we are constantly exploring the subject, currently there is no direct evidence that links cell phone usage to brain cancer.” </li></ul>
  39. 42. Chapter 11: Doctoring Evidence A Breast Cancer Fund poster, banned in San Francisco in January of 2000. The superimposed mastectomy scars are those of the author’s friend, Andrea Martin. 
  40. 44. Latinas put phones in bras Dominican Republic, Credit Thos Robinson, 2010
  41. 46. French Government Proposed Restrictions on Cell Phones, January, 2009 <ul><li>Ban advertising to children under 12 </li></ul><ul><li>Ban design of phones to be used by those under six. </li></ul><ul><li>  </li></ul><ul><li>Handsets must be sold with phones </li></ul><ul><li>City of Lyon official advertising campaign to discourage the use of the phones by children. </li></ul>
  42. 47. Finnish Authorities Warn of Cell Phone Risks to Children and Those with Pacemakers <ul><li>Use text messages rather than calls </li></ul><ul><li>Use hands-free devices, with phone kept away from the body, </li></ul><ul><li>Avoid talking in an area with low connectivity </li></ul><ul><li>Disruption of pacemakers is usually harmless, but can increase heart beat </li></ul>
  43. 48. CTIA, 2010 <ul><li>Opposes Right to Know about Cell Phone Radiation in San Francisco, Maine, and Burlingame—will confuse people </li></ul><ul><li>When asked, why fine print warnings come with all phones now, Dane Snowdon, replied, “We’ll get back to you.” </li></ul><ul><li>Mr. Snowdon, six months later we want to know the answer </li></ul>
  44. 49. Fine Print Warnings
  45. 50. Fine Print Warnings
  46. 51. Fine Print Warnings (iPhone 4)
  47. 52. Models Wanted – No Experience Necessary Must be willing to protect their brains and practice safe phone
  48. 53. Warning Proposed for State of Maine, March 2010, to prevent brain cancer and other chronic illnesses Warnings Proposed by Secretary of Transportation Ray LaHood to Reduce distracted driving deaths and accidents
  49. 54. Join the Campaign for Safer Cell Phones <ul><li> </li></ul><ul><li>Facebook Campaign for Safer Cell Phones </li></ul><ul><li>Volunteer for Grandparents campaign to provide holiday headsets and warnings to grandchildren </li></ul>
  50. 55. <ul><li>The world is not dangerous because of those </li></ul><ul><li>who do harm but because of those who look at </li></ul><ul><li>it without doing anything. </li></ul><ul><li>Albert Einstein </li></ul><ul><li> </li></ul>