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Community Environmental Monitoring Program

Learn about the role of radiation in cancer development and how to minimize exposure through environmental monitoring and lifestyle changes. Dr. Antone L. Brooks provides insights from his extensive research in radiation biology and genetics.

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Community Environmental Monitoring Program

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  1. Community Environmental Monitoring Program Dr. Antone L. Brooks July, 2011 Brian Head, Ut

  2. My Background • Early interest in radiation (Watching atomic weapons in Southern Utah) • MS in radiation ecology (Chasing fallout),PhD in radiation biology and genetics • Studied health effects induced by low doses from internally deposited radio-nuclides • Invested my life in research on genetic effects and cancer from low doses and dose-rate radiation (DOE Low Dose Radiation Research Program)

  3. Bad Diet Why Me?? Drinker Radiation Smoker

  4. RADIATIONI am Blamed for much Human Disease • Cancer of all kinds • Mutations • Birth Defects • Heart attacks • Stroke

  5. I have even been blamed for !!! Ninja Turtles Spider Man Incredible Hulk

  6. I am natural, Radiation is everywhere Cosmic Inhaled Radon Bodies Plants Radioactive Elements Rocks We live in a sea of radiation…

  7. Normal annual exposure from natural radiation About240 mrem/yr • Radon gas 140 mrem • Human body 40 mrem • Rocks, soil 30 mrem • Cosmic rays 30 mrem About 300 mrem/yr • Medical procedures 280 mrems • Consumer products 10 mrems • One coast to coast airplane flight 2 mrems • Watching color TV 1 mrem • Sleeping with another person 1 mrem • Weapons test fallout less that 1 mrem • Nuclear industry less than 1 mrem Normal annual exposure from man-made radiation

  8. U.S Dose Rates from Natural Background

  9. Nevada Test Fallout Simon et al. 2006

  10. World wide fallout in the United States

  11. Race White 136/100,000 Black 294/100,000 Sex Males 60.6% Females 39.4% Geographic DistributionNo link between high Background Radiation and Cancer Areas with top 10 percentile of cancer= 231-892 cancers/100,000 person-years (low background) Areas with lowest 10 percentile of cancer= 93-168 cancers/100/000 person-years (high background) Cancer Rate is Highly Variable

  12. What Causes Cancer? I am not a big hitter!!!

  13. What Radiation Exposures Can we Modify?

  14. What Radiation Exposures can we Modify?

  15. Medical Radiation Exposures, YES, BUT I DO A LOT OF GOOD!!! • 200 million medical x-rays/year • X-ray 0.1 mGy • 100 million dental x-rays/year • Dental 0.06 mGy • 16 million doses of radiopharmaceuticals/yr • 80 million CT scans/year • Head scan 4-6 mGy/scan • Body scan 30-100 mGy/scan • Large doses from radiation therapy Brenner and Hall AAPM TG-204, 2011

  16. What about the A-Bomb!! You did a lot of damage there. • Cancer • Mutations • Birth Defects • Heart attacks • Strokes

  17. Killed outright by the bomb or acute radiation effects. Survived for lifespan study More than 200,000 people 86,572 people Effects of the Atomic Bomb

  18. 5% less cancer than total controls 2.45 Km (5 mSv) 3 Km (2 mSv) 46,249 “Exposed” 5 Km 10,159 “Controls” A-BOMB SURVIVOR STUDIES Pierce and Preston 2000

  19. A-BOMB SURVIVOR STUDIES 3 Km Preston et al. 2004 CONTROL AREA 2. Km Excess Excess Solid Tumors Leukemias 1 Km 113 116 99 41 44 2 28.2 27.7 18.9 10.4 4.7 4.0 0.1 64 572 Total Excess Cancers 479 Total 93 Total

  20. Atomic Bomb Survivor Excess Cancer Population of Survivors Studied86,572 40% of these people are still alive 60 years after the bomb Cancer Mortality observed after the bomb 10,127 Cancers Mortality observed without the bomb 9,555 Total Cancer Mortality Excess572 Excess Solid Tumor 479 Excess Leukemia 94 + = 572

  21. Where do we get these excess cancers??Aggregation of data on Solid Cancers • Total Solid Cancers 9555 • Stomach 2867 • Life Style, Diet, stomach bacteria • Liver 1236 • Long Latency • Influence of chronic Infections • Alcohol • Lung 1264 • Smoking • Non-linear Dose-response Preston et al. 2003

  22. Biology of Solid Cancers • Can we really group all Solid Cancers then apply the LNT to estimate responses at low doses? • Stomach Cancer • Lung Cancer • Liver Cancer • All these cancers are known to be produced by environmental factors • Bone Cancer • Lung Cancer • These cancers have very non-linear Dose-Response Relationships • Thyroid Cancer • Prostrate, Pancreas, Uterus, Rectum???

  23. Aggregation of Solid Cancer: Influence on Policy • Pay for the types of cancers seen to be elevated in the A-bomb population. • Solid Cancers • Leukemia • Current Pay-out Cancers for Down-Winders, Nuclear Veterans, Uranium Miners • Bone, renal, leukemia, lung, multiple myeloma, bile duct, brain, breast, colon, esophagus, stomach, bladder, gal bladder, liver, ovary, pharynx, salivary gland, small intestine, thyroid, lymphoma (five years after exposure) • Current payout • RECA = 1.3 Billion • EEOICA = 3.2 Billion

  24. Interaction with Environmental factors (I get the blame!!!) • Smoking and Uranium mining • Radiation and alcohol • Radon in homes

  25. Radon in Homes (BEIR VI) • Total Cancers Ever-Smokers Never Smokers 157,000 146,400 11,000 Radon induced Cancer Total Cancers Ever-Smokers Never Smokers (Exposure-age-Concentration model) (Radiation only) 22,300 20,600 1,700 (Exposure-age-Duration model) 15,500 14,600 1,200

  26. What about when you get deposited in the body?? • Inhalation and lung cancer • Low dose rate and non-uniform distribution • Deposition in target organs • Strontium-90 Bone • Iodine -131 Thyroid Cancer • Cesium-137 Whole Body Exposure • Tritium Whole Body Exposure

  27. Dose Dose-Rate Effectiveness (DDREF) Factor is it 1.0? • Dose-Dose-Rate-Effectiveness-Factor (DDREF), regulatory bodies considering making it (1.0) • Dose-rate has a marked effect at all levels of biological orgainztion • All you have to do to make DDREF 1.0 is accept a couple of low dose-rate epidemiological studies which cannot demonstrate a difference in risk for high and low dose rates • All you have to do to make a DDREF of 1.0 is to ignore 70 years of radiation biology

  28. Dose-Rate Effects at all Levels of Biological Organization • Molecular • Cellular • Tissue • Whole Organ • Cancer • Life Shortening

  29. Dose and Dose-Rate Effects DDREF derived with curve fitting of the human data. • DDREF 1.5 BEIR VII • DDREF 2.0 ICRP (2007) • DDREF 1.0 Considered by Germans DREF derived from animal and experimental data. • Experimental Molecular/Cellular 4-??? • Chromosome Aberrations 4-6 • Mouse data • Lung Adenocarcinomas 3-7 • Ovarian Tumors 7-35 • Thymic lymphoma 10-30 • Mammary tumors 1-4 • Myeloid Leukemia 2-6 • Dog Data • (Acute Death Bone Marrow) 3-4 • (Acute Death Lung) 10-100 • Dog Data (Cancer) 15-40

  30. Summary DDREF • A large dose-rate effectiveness factor is required due to the marked decrease in biological effects observed following low dose-rate radiation exposure. • At radiation doses less than 20 Gy (20,000 mGy) to the lung following inhalation of radioactive materials, there is little life shortening and a decrease in the frequency of lung cancer. • When the dose delivered at a low dose-rate gets very, very large (80-220 Gy in Bone and 100-700 Gy in lung), the cancer frequency approaches 100%. • At low dose-rates the total dose required to produce acute radiation lethality is similar to the dose required to produce a high cancer frequency. • Genetic background plays an important role in the response to large total radiation doses delivered at a low dose-rate. • Such data should be considered in decisions about evacuation (10-50 mSv projected dose) and relocation (20 mSv projected dose first year) of the public following radiation accidents or terrorist events. Current research suggests that the mechanisms of action of these very large doses delivered at low dose-rates are different to those after acute low doses. Should we consider separating DDREF from DREF?

  31. Cancer in Beagle Dogs following Acute Radiation Exposure Benjamin et al 1998

  32. Dose Response for Life Shortening Following Inhalation of 90-Strontium Fused Clay Particles Cancer Other Heart Cancer Lung Cancer TBLN Cancer Acute

  33. All cancers Control dogs Total Cancer and Lung Cancer Control dogs Lung cancer 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0 Percent of Dogs with Cancer 0 5 10 15 20 25 Total dose to lung (Gy)

  34. % Total Cancer (Controls) by Location

  35. % Lung Cancer (Control) by Location

  36. LNT FIT ITRI Exposed

  37. Selection of Proper Controls?? • Dog Data • Add more control dogs for greater accuracy • Adding dogs greater genetic variation • Adding dogs different environmental and life styles • Human Data • Match controls for life-style, stress and environment, Age, Sex etc. • “the distal group has about 5% higher cancer rates than estimated for zero dose from the proximal group.” (Pierce and Preston 2000) • Adding more people increases variation in genetic variation, record keeping, environment, life-style.

  38. How much is a Bq? • Scientific definition • Social definition • Risk • Will I be OK?

  39. Comparing Environmental and Health Effects (Bq?) • The levels in the environment are very non-uniform • The amount of radiation required to produce health effects is much higher than that in the environment (large safety factor) • There is a decrease in effectiveness with partial body exposures • There is a decrease in effectiveness with decreasing dose-rate.

  40. Mechanistic Studies of Low Dose Effects • The risk for radiation induced cancer in human populations is low and undetectable at low doses and dose-rates thus mechanistic studies are required. • DOE Low Dose Radiation Research Program http://www.lowdose.energy.gov • Cells can detect and respond to very low doses of ionizing radiation • Radiation responses at all levels of biological organization are different at high doses than at low doses. • High dose-rate produces more biological damage than low dose-rate exposures • Bystander effects, adaptive responses, ROS status of the cells, and genomic instability are interrelated and can be related to protective mechanisms. This resulted in major paradigm shifts in Radiation biology. • Thus, mechanisms of radiation action change as a function of dose and dose-rate. Data suggest that radiation exposures are detrimental at high doses and protective at low doses.

  41. Mechanistic studies of Low Dose Effects • Cells can detect and respond to very low doses of ionizing radiation • Radiation responses at all levels of biological organization are different at high doses than at low doses • Thus, mechanisms of radiation action change as a function of dose. Data suggest that they are detrimental at high doses and protective at low doses. • Low Dose research require paradigm shifts in radiation biology to support the data. • Bystander effects, adaptive responses, ROS status of the cells, and genomic instability are interrelated and can be related to protective mechanisms. • The risk for radiation induced cancer in human populations is low and undetectable at low doses and dose-rates. • Linear low dose (LNT) extrapolation is not supported by low dose radiation research

  42. Helpful Reviews of Health Effects from Low dose and dose-rate radiation • Health Physics 97: November 2009, Special Issue: 44th Annual Meeting of the National Council on Radiation Protection and Measurements: Low Dose and Low Dose-Rate Radiation Effects and Models. • Dauer, LT, Brooks, AL, Hoel, D, Morgan W, Stram D, Tran P. (2010) Evaluation of updated research on the health effects associated with low-dose ionizing radiation, Radiation Protection Dosimetry140 (2) 103-136. • Health Physics 100:, March 2011, Special Issue: Proceedings of the Conference on Biological Consequences and Health Risks of Low-Level Exposure to Ionizing Radiation: In honor of Victor P. Bond.

  43. Radiation Risk: What Is the Public Perception? • Radiation is very bad • There is good and bad radiation, (Medical and Environmental) • Each and every ionization increases their risk for cancer (LNT) • Many conclude that if you are exposed to radiation you are going to get cancer • If you were exposed to radiation and you get cancer the radiation caused the cancer

  44. It is not all my Fault!! At low doses I do way more good than harm!!!

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