Cancer & the Environment: What is known, & what can we do to prevent cancer?

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2 Cancer & the Environment: What is known, & what can we do to prevent cancer? John McLaughlin VP, Population Studies & Surveillance, Cancer Care Ontario Professor, Public Health Sciences, U of Toronto Senior Investigator, Samuel Lunenfeld Research Institute Leader, Prevention Programs, Ontario Institute for Cancer Research Hamilton May 28, 2008

3 Outline Cancer concerns Cancer prevention and control in Ontario How are environmental causes of cancer detected and monitored? What is known about cancer causes? What can be done about the environment to prevent cancer? Varying environments and their impacts Conclusions

4 Cancer is a major concern: Each year there is more cancer around us.

5 Causes of Cancer What most people say Respondents were told: Recent statistics indicate that 33% more people will get cancer in 2015 than today And then asked: What do you feel are the main factors behind the growing number of people with cancer? (in order of importance) Pollution and chemicals in the environment 51% Unhealthy lifestyles, diet and lack of exercise 25% Aging and population growth 13% Genetic factors 9% IPSOS Poll 51% of respondents felt that pollution and chemicals in the environment are the main factors

6 Ontario Cancer Plan Understand & reduce exposure to carcinogens S I X G O A L S 1 Reduce the incidence of cancer 2 Reduce the impact of cancer through effective screening & early detection 3 4 Ensure timely access to effective diagnosis and high quality cancer care Improve the patient experience across continuum 5 Improve the performance of cancer system 6 Strengthen translation of research into improvements in cancer control Available at AGM

7 Cancer Care Ontario Cancer Care Ontario is the provincial agency responsible for continually improving cancer services. As the government s cancer advisor, Cancer Care Ontario: Directs and oversees more than $600 million public health care dollars to hospitals and other cancer care providers to deliver high quality, timely cancer services. Implements provincial cancer prevention and screening programs designed to reduce cancer risks and raise screening participation rates. Works with cancer care professionals and organizations to develop and implement quality improvements and standards. Uses electronic information and technology to support health professionals and patient self-care and to continually improve the safety, quality, efficiency, accessibility and accountability of cancer services. Plans cancer services to meet current and future patient needs, and works with health care providers in every Local Health Integration Network to continually improve cancer care for the people they serve. Rapidly transfers new research into improvements and innovations in clinical practice and cancer prevention and control programs.

8 Ontario s Cancer Prevention Plan: Report on Cancer 2020 (2003 & 2006 update) Long term cancer prevention and early detection strategy Targets aimed to reduce the incidence of and mortality from cancer by the year 2020 Highlights provincial initiatives Measures and monitors progress against targets Sets out recommendations for sustained action Available at

9 Cancer 2020 Provincial Targets Cancer Prevention Targets Tobacco use Diet and nutrition Healthy body weight Physical activity Alcohol consumption Occupational/ Environmental carcinogens Ultraviolet exposure Viral infections Cancer Screening Targets Breast cancer Cervical cancer Colorectal cancer Emerging Issues Medications and supplements New developments in screening

10 Cancer 2020 Action Plan Includes targets and areas of activity regarding carcinogens in the general environment and at work

11 Insight Report on the Environment & Cancer - Published by CCS and CCO with multiple partners (2005) Extensive review of literature and evidence, with the following conclusions: Evidence supports an association with at least one cancer Air pollution (lung), Arsenic in drinking water (bladder, skin, lung), Asbestos (mesothelioma), Water disinfection byproducts (bladder), ELF magnetic fields (childhood leukemia), Solar radiation (skin), radon (lung) Inconsistent evidence of an association Endocrine disruptors, Pesticides Data are insufficient to assess the association Metals, Polyaromatic hydrocarbons, Radiofrequency fields, Available at

12 Causes of Cancer What most people say Respondents were told: Recent statistics indicate that 33% more people will get cancer in 2015 than today And then asked: What do you feel are the main factors behind the growing number of people with cancer? (in order of importance) Pollution and chemicals in the environment 51% Unhealthy lifestyles, diet and lack of exercise 25% Aging and population growth 13% Genetic factors 9% IPSOS Poll 51% of respondents felt that pollution and chemicals in the environment are the main factors

13 Causes of Cancer What the Science Says (after accounting for age and sex) Attributable Risk (% of disease due to risk factor) Tobacco Diet/Obesity/Physical Activity Occupation/Environment RISK FACTOR Family History Biological Agents Perinatal Effects/Growth Alcohol Reproductive Factors Radiation/Sunlight Other/Unknown IPSOS Poll PERCENT Adapted from Adami et al., 2001 and Colditz et al.,1996)

14 Trends over time (Canada from 1978 to 2007) Incidence Rates are steady (line) while the Number of Cases keeps rising (bar) Source: Canadian Cancer Statistics 2007

15 Number of newly diagnosed cancer cases Aging & Growing Population are Driving Increased Cancer Incidence Population Pyramid

16 What can be done to PREVENT Cancer? Consider where cancer happens, and among whom To identify causes and risk factors for specific types of cancer

17 Most frequent cancers in Canada (2007) 3 types of cancer account for > 55% of all new cases Males: prostate, lung, colorectal Females: breast, lung, colorectal Source: Canadian Cancer Society, Canadian Cancer Statistics 2008

18 Lung Cancer in Ontario Males (compared to the provincial average) Researchers & public health workers can identify places with more (or less) cancer than expected Source: Ontario Cancer Registry

19 Explanations for Variation in Cancer Risks (a few examples of risk factors for common cancers) Lung: Tobacco smoke (the major preventable cause of cancer - still), Age, Radon, Occupational factors (asbestos, exhaust) Prostate: Increased screen detection, Age, Race, Family history, Diet (meat, fat, vegetable), Alcohol Colorectal: Age, Personal history of polyps or ulcerative colitis, Family history of colorectal cancer or polyps, Diet (vegetable, fruit, meat, fat), Tobacco smoke, Alcohol

20 Trends a rare cancer of the lung lining (mesothelioma) Public Health Unit regions Source: Ontario Cancer Registry

21 Asbestos is a rare cause of lung cancer, and the cause of a rare cancer of the lung lining (mesothelioma) Source: Ontario Cancer Facts

22 What is a Carcinogen? Any substance or agent that can cause cancer. These may be chemical substances, physical agents (e.g., asbestos, dust) or biological agents (e.g., virus, bacteria). Research to discover & understand carcinogens: Observational studies of humans (epidemiology) Animal experimentation (toxicology) Basic sciences (molecular biology)

23 How are carcinogens identified and classified? Identified by reviewing the world literature from all areas of research Led by the International Agency for Research on Cancer (IARC in France) Publish reports that summarize the evidence, available at Classified as: Group 1 Proven to be carcinogenic in humans Group 2A Probably carcinogenic Group 2B Possibly carcinogenic Group 3 Not classifiable Group 4 Not carcinogenic

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26 The Global Environment Establishing the imperative for sustainable solutions Consider Air Pollution

27 One Example of Environmental Carcinogen Monitoring - Trends in Benzene in Air in Ontario ( ) Source: National Air Pollution Surveillance Network

28 Air Pollution Nitrogen Oxides (Nox) highly reactive gases, containing nitrogen and oxygen in varying amounts some are colorless and odorless, but NO2 along with particles is a reddishbrown layer seen over urban areas primary sources are fuel combustion fromo motor vehicles, electric utilities, industrial sources etc. exposure can be measured by:

29 Carcinogens at Work CAREX is the International Information System on Occupational Carcinogen Exposure, developed in Finland over the past decade. Inititially developed to estimate European and U.S. exposure to established (#1), probable (#2) and selected possible (#2b) to occupational carcinogens. Recent adaptation to other locations, and extension from occupational to environmental exposures. Preliminary adaptation to Ontario for occupational exposures (see figure).

30 CAREX (CARcinogen Exposure) Project Rank order of in terms of number of workers potentially exposed to carcinogens in the workplace (preliminary estimates) Crystalline silica Wood dust Diesel exhausts Benzene Lead Chromium VI Glass wool Tetrachloroethylene Polyaromatic hydrocarbons Nickel compounds Formaldehyde Asbestos Source: Dr. Marrett (CCO) # of workers exposed

31 The workplace is an important setting: To detect health effects of occupational factors that may affect others through environmental exposures at lower doses To monitor exposures and health outcomes For cancer prevention

32 Carcinogens in tobacco smoke Source: Hecht, Nature Reviews Cancer 2003.

33 Carcinogens in tobacco smoke Source: Hecht, Nature Reviews Cancer 2003.

34 Smoke Free Ontario By the Ontario Ministry of Health Promotion Comprehensive SF-O Strategy has three goals: preventing children and youth from starting to smoke helping Ontarians quit smoking; and protecting Ontarians from involuntary smoke Components: Youth programs Cessation programs Aboriginal programs Evaluation and Surveillance Provincial support programs (training and technical assistance) Health department programs

35 How does the Environment affect us? At many levels and in many ways A Social-Ecological Model of the levels of influence on an individual

36 Smoking Cessation & the Social Environment Strong addiction makes quitting extremely difficult Successful quitting requires many factors, determinants and supports It is not just about individual behaviour. in the news Smokers Often Quit for Social Reasons Study Suggests Efforts to Quit Smoking May Be Contagious May 22, 2008 New England Journal of Medicine: The decision quit is strongly influenced by the people around you. Social influences played a large role in the dramatic declines in smoking over the past few decades. Workplace smoking cessation programs are effective, well received, empowering, enabling

37 Cancer Prevention Many cancers are preventable. About 1/3 of cancer deaths are attributable to tobacco. Another 1/3 are attributable to diet, unhealthy body weight and inactivity. Our goal is to reduce risk factors for the people of Ontario.

38 Making the healthy choice the easy choice for all ages (the Food Environment)

39 Physical Activity for all ages (the play environment)

40 Walkability at work Consider our workplace and urban design. Does it promote health for staff, patients, families?

41 Walkability at work Can you get to work without driving? Can staff and visitors walk to shop, eat, stretch?

42 Obstacles to overcome Safety fears: making the environment safer and more pleasant, encourages exercise Time and money: gyms can be expensive, and working people may not have the time Dislike sports: No need for a gym; 30 minutes of walking at 3mph burns about 170 kcal (calories in 400ml of pop) Unattractive environment: A few changes can make a big difference (eg. Stairwells) Before After Natural England health conference 18 June 2007 slide 42 Source:

43 To sustain efforts to, progress must be made in integrated and beneficial programs Learn from successes & challenges in tobacco control Now target other causes and risk factors, for which there is evidence, exposure, dose, and biological effect, and human susceptibility, among individuals and across the population Galen, 200 AD but remember no cause is efficient without a predisposition of the body itself. Otherwise, external causes which affect one, would affect all

44 How to Reduce Cancer Risk? 7 Steps to Health (Canadian Cancer Society) Don t smoke. Avoid second-hand smoke Eat healthy food, limit alcohol Be active Be sun safe Follow cancer screening guidelines Report changes in your health to a doctor Use caution with hazardous materials