Lecture 16: Review, Pressure/State/Response and Heavy Metals and Cancer and the Environment

1. Lecture 16: Review, Pressure/State/Response and Heavy Metals and Cancer and the Environment

2. Some final words on water…. • Boil water advisories: • Mostly to kill fecal coliform bacteria • Estimates range from 1-5 minutes • Boiling is not helpful for heavy pollution or chemical contamination • Giardia is resistant to chlorine • In BC, 240 boil water advisories currently serve ~ 15,000 people • Since 1985 there have been 18 outbreaks of water-borne disease

3. Some final words on water…. • Bottled water: • Look for reverse osmosis, ozonation and distillation • Testing your water: • Environmental health division of your local health unit or health dept. The Environmental health officer should be able to help you with what to test for in your area FYI: Seymour Filtration Plant presentation http://www.gvrd.bc.ca/water/pdfs/SLWaterSystemOverview040114.pdf

4. Review: Key Concepts and Learning Objectives Learning Goals: • Vulnerable Populations: Occupational exposures: Why are workers vulnerable and what can be done to protect them? • The Precautionary Principle: what is it, how we can use it and how does it relate to scientific uncertainty? • Global warming and climate change: what are the range of anticipated effects?

5. Key Concepts and Learning Objectives Learning Goals: • Global warming and climate change: what are the anticipated effects and implications for human health? • Greenhouse gases • Infectious diseases range • Ground level and upper atmosphere ozone • How is British Columbia unique and what progress has been made here?

6. Key Concepts and Learning Objectives Learning Goals: • Air pollution: what are the differences between area, point and linear sources? • When we talk about multiple sources, multiple routes and multiple interactions what do we mean? • What types of air pollution do we monitor most regularly in Canada? • Why are temperature inversions problematic for air pollution levels?

7. Key Concepts and Learning Objectives Learning Goals: Water: What are the important sources of water consumption? What are the basic processes in water treatment? Where does the majority of our water come from? What are MACs, TDIs and NOAELS? What are the major chemical and biological threats to water? How are we doing in British Columbia with regard to water quality?

8. “Environmental epidemiology/environmental Health” Dade Moeller, 1992 4 steps to examining environmental health 1. Determine the source and nature of each environmental contaminant or stress. 2. Assess how and in what form it comes into contact with people. 3. Measure the effects. 4. Apply controls when and where appropriate.

10. WHO DPSEEA model for environmental health

11. Pressure- State- Response • P1,P2… Human activities that put pressure on the environment  Land, air and water • S1, S2… States of ambient environment quality • I1, I2, I1… Human Health, Ecosystem Health, Economic and Social • Aesthetic Impact due to ambient consequences • R1, R2… Policy Responses Hello Mom!

14. Human Health and Heavy Metals • Wide dispersion • Tendency to accumulate • Ability to do damage/be toxic at low levels GLOBAL CONCERNS AND LOCAL TOXIC HAZARDS WASTE 1 lead, 2 mercury 3 arsenic, 6 cadmium

15. Human Health and Heavy Metals • Routes of Exposure: • Food • Inhaled

16. Human Health and Heavy Metals LEAD – most studied Sources: Lead organic compounds such as motor vehicle fuel Batteries (MV) Pigments, glazes, solder, plastics root vegetables water with low pH ceramic glazes,

17. Human Health and Heavy Metals LEAD Dose: 5-25 ug/L children must stay below 40 ug/L workers Lead organic compounds such as motor vehicle fuel Batteries (MV) Pigments, glazes, solder, plastics root vegetables water with low pH ceramic glazes Toxicity: IQ, hypertension, convulsions, coma, renal failure Canada drinking water IMAC 10 ug/L

18. Human Health and Heavy Metals MERCURY Sources: thermometers, dental amalgams, batteries must stay below 40 ug/L workers Exposure: -If left standing or aerosolized it is taken into lungs -Dispersed through waste incineration -soil and water deposits; converted into methyl mercury by microorganisms then bio-concentrated up the food chain (fish, tuna, mackerel)

19. Human Health and Heavy Metals MERCURY Toxicity: Tremors, memory loss, excitability, insomnia, delirium – “mad as a hatter” Readily crosses the placenta and appears in breast milk Minimata Japan 1955: mental retardation, cerebellar symptoms CANADA MAC 1 ug/L below levels found

20. Human Health and Heavy Metals ARSENIC Sources: earth’s crust, smelting industry, wood preservatives, pesticides, paints, fossil fuel combustion, folk remedies, wells Exposure: toxic and carcinogenic. Scientists are debating safe exposure standards

21. Human Health and Heavy Metals ARSENIC Toxicity: - Depends on its valence state (0, 3, 5 valent) and its form (inorganic or organic) - Inorganic is most toxic • Collects most in skin, hair and nails • can lead to skin, liver, lung, bladder and kidney and colon cancer • skin hyperpigmentation, peripheral nerve damage • US drinking water guideline is 50 ug/L considered too high • Canada IMAC 25 ug/L

22. Human Health and Heavy Metals CADMIUM: Source: toxicity is relatively uncommon but exposure causes distinctive clinical syndromes Exposure: Industries dealing with pigment, metal plating, plastics, batteries Cadmium pollution introduces cadmium into sewage sludge, fertilizers and groundwater resulting in contamination in foodstuffs, grains, cereals and leafy vegetables -cigarette smoking

23. Human Health and Heavy Metals CADMIUM: Toxicity: • complicated by inability of humans to excrete cadmium (b/c reabsorbed by kidneys) • Chronic lung disease, testicular degeneration, prostate cancer? • Kidneys ; effects tend to be irreversible • Itai-itai disease in Japan contaminated rice stocks ; also bone fractures

24. Prescriptions • Even though well studied still need to know about lead: • and subpopulations • and reversible effects on mental development and children • Role in degenerative diseases like Alzheimer’s and Parkinsons

25. Prescriptions • Accelerate phase-out of leaded gasoline • Italy, Greece, Spain, Australia, Chile lag • South Africa, Nigeria, Israel haven’t committed • Monitor trends world wide: • Take regular samples, standardize methods, find out about levels in air, water and foods • Establish population-based monitoring for metals • Educate governments, scientists and public on metal toxicity • Declare moratorium on production/dist./use of heavy metals • Continue basic research on impacts of heavy metals on human health

26. Exposure Histories • Description of the patient’s past and present jobs • Listing of materials in the home, yard, garden, garage or shop • Exposure at school, travel and play • Living in proximity to industrial plants or contaminated drinking water • Dietary history • Smoking and alcohol consumption • Recreational and medical drugs

27. Cancer and the Environment • 1. the background of cancer incidence and mortality • 2. types of exposures that are known or suspected causes of cancer clusters • 3. implications for health care providers who wish to provide guidance for worried patients or communities

28. Cancer and the Environment • Last 25 years • US Age-adjusted all sites: • 320/100,00 in 1973 to 395/100,000 in 1998 • CANADA Age-adjusted all sites: • 280/100,00 and 338/100,000 in 1972 for males and females respectively • to 344/100,000 and 444/100,000 in 2001

29. Sites with decreasing incidence and mortality Oral cavity and pharynx Stomach Colon Pancreas cervix and uterus Hodgkin’s disease Leukemias breast Sites with increasing incidence and mortality Esophagus Liver Lung Melanomas Prostate Kidney Brain *Non-Hodgkin’s lymphoma Multiple myeloma Cancer and the Environment: Trends 1973-1998 * Associated with environmental and occupational exposures

30. Cancer and the Environment Lifetime risk: US 43% for males and 38% females Canada 40% for males and 36% females Harvard Centre for Cancer Prevention: • 30% cancer deaths due to tobacco • 30% adult diet/obesity

31. Cancer and the Environment Melanoma of the skin Non-Hodgkin’s lymphoma exposure to UV light, to herbicides, genetic factors, viral exposures

32. Cancer and the Environment Communities at risk: • workers, facilities • Medical waste incineration • Canadian National Pollutant Release Inventory

33. Summary • Live well • Exercise • Quit or Don’t smoke • Eat healthy • Use protective equipment when necessary • Minimize exposures when possible • Be an advocate

34. References • Clapp, R.W. (2002) Cancer and the Environment, Ch 11, Life Support, the Environment and Human Health, ed., M. McCally, MIT Press, USA. • Hu, H. (2002) Human Health and Heavy Metals Exposure, Ch 5, Life Support, the Environment and Human Health, ed., M. McCally, MIT Press, USA.