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Home , Particle accelerator

Unexpected Exposure Scenarios

Timur Durrani, MD, MPH, MBA Associate Professor of , UCSF Site Occupational Medical Director, LBNL March 7, 2020

Outline

• The Advanced Source (ALS) • Expected scenarios • Review of types of radiation • Overview of radiation assessment • Examples of radiation injury and treatment • Unexpected radiation exposure scenarios The (ALS)

A specialized accelerator that generates bright beams of x-ray light for scientific research. bunches travel at nearly the speed of light in a circular path, emitting and x-ray light in the process. The light is directed through about 40 to numerous experimental end stations, where scientists can conduct research in a wide variety of fields, including materials , biology, chemistry, , and the environmental sciences. The wavelengths of the light span the electromagnetic spectrum from to x-rays and have just the right size and range for examining the atomic and electronic structure of .

ALS Beamlines

The Electromagnetic Spectrum

https://www.ehs.washington.edu/radiation/non-ionizing-radiation-safety http://nuclearsafety.gc.ca/eng/resources/radiation/introduction-to-radiation/types-and-sources-of-radiation.cfm

Annual outdoor effective dose from cosmic radiation for North America, 2004

http://nuclearsafety.gc.ca/eng/resources/radiation/introduction-to-radiation/types-and-sources-of-radiation.cfm

Metals in Earth’s crust Abundance ( fraction) of the chemical elements in Earth’s upper continental crust as a function of atomic number.

U.S. Geological Survey Fact Sheet 087-02 Exposure to the Public

USNRC Technical Training Center: https://www.nrc.gov/reading-rm/basic-ref/students/for-educators/06.pdf

The atom

Radioactive Decay How x-rays work

Types of Ionizing Radiation

Alpha – concern for internal contamination (i.e. ) Beta – concern for internal and external contamination Gamma – like X-rays, but emitted from nucleus, X-ray emitted from . Concern for internal contamination. – uncharged from the nucleus. More potent than Gamma Rays. Have the ability to make something else radioactive.

Ionizing Radiation

Paper Plastic Lead Concrete α

β

γ Periodic Table

Categories of

University Five 14C, 32P, 125I, 131I, 252Cf Industrial three: 192IR, 137Cs, 60Co Military five: 3H, 235U, 238U, 239Pu, 241Am Fission/Activation products: • Iodine • Strontium • Cesium • •

How Fission works

Large atom (Plutonium) bombarded with neutrons, causes the atom to split (fission) in uneven products Plutonium (235) = Strontium (87) + Cesium (132) + Neutrons The core of a fission bomb is either plutonium or highly enriched uranium. These are the only materials that can achieve a self- sustaining chain reaction. Example

Chain reaction

Fission Yield of U-233, U-235, P-239 Fission Yield % Fission Yield

Atomic Mass Types of Fission Materials

Uranium – 235 (comes out of the ground) • 5% used in reactors • 20% used in weapons Plutonium (comes out of a lab)

Units

Curie (Ci) basic unit of radioactivity in US Dose refers to the absorption of radiation energy per unit mass of absorber. The conventional (USA) dose unit is the rad. The SI dose is the Gray. • 1 Gy = 100 rad

Annual Regulatory Limits (US NRC)

Non-Occupational rem ~Gray

Members of the Public 0.1 0.001 Occupational Whole Body (internal + external) 5 0.05 Any individual organ 50 0.5

Lens of the Eye 15 0.15 Skin 50 0.5 Extremities 50 0.5 Fetal Dose (declared pregnancy) 0.5 0.005 How this works practically

Source is determined to be α,β, or γ using the Geiger Counter Geiger Counter takes initial measurement (in counts per minute). This gets converted to Rad/Rem and compared to the Annual Regulatory Limits to determine if it is a medical/regulatory problem

Medical Testing

Andrews Lymphocyte Example Nomogram Nasal Swab CBC w/diff Dicentromere cytogenetics Bioassays (urine/feces).

Andrews, G.A., Lushbaugh, C.C., & Auxier, J.A. (1965). The Importance of to the Medical Management of Persons Accidentally Exposed to High Levels of Radiation. International Atomic Energy Agency (IAEA): IAEA. Strange and Schafermeyer's Pediatric Emergency Medicine, Fourth Edition (Strange, Pediatric Emergency Medicine) 4th Ed. CHAPTER 142 Radiation Emergencies

Radiation exposure is toxic exposure

Radiation is toxicity by energy Mechanism of action: breaks chemical bonds in DNA, produces and free radicals Dose estimation: depends on type of agent, activity of agent, and exposure Exposure is dependent on duration of exposure (time) proximity of exposure (distance) and protection (shielding) Radiation injury appears depending on dose

Higher doses cause injury sooner (days) than lower doses (weeks). – Immediate: Redness, swelling, blisters, ulceration, tissue necrosis – Delayed: Fibrosis, atrophy (sclerosis), and telangiectasia formation, cancer

Acute Radiation Syndromes Dose (Gray) Syndrome Effects 1-2 Hematopoietic ~100% Survival without treatment

3-5 Gastrointestinal LD50/60 without treatment

6-8 LD50/60 with supportive care 9-10 Consider Stem Cell transplant 10+ Neurovascular Multiple Organ failure, probable death

LD50/60 - 50% death of exposed in 60 days

Cutaneous Radiation Injury

Dose (Gray) Injury Onset 3 Epilation (hairloss) 14 – 21 days 6 Erythema Waxes/Wains, early as few hours to 14 – 21 days 10 – 15 Dry desquamation 20 days 15 – 25 Wet desquamation 14 – 21 days Exposure scenarios

Electron Accelerator Accident INTERNATIONAL ATOMIC ENERGY AGENCY, An Electron Accelerator Accident in Hanoi, Viet Nam, , IAEA, Vienna (1996).

Diagram of accelerator facilities and offices

Footer 33 Diagram of the microtron accelerator Diagram of exposure position

Local Injury

Day 14 Day 28

Footer 35

Ongoing

Day 113 Estimated dose to right hand

Footer 36 Uncontrolled medical therapy source, Cs137

INTERNATIONAL ATOMIC ENERGY AGENCY, The Radiological Accident in Goiania, IAEA, Vienna (1988).

Footer 37

Abandoned Radiotherapy Clinic

Radiation Therapy Schematic

Footer 39 Cesium Chloride

Source Capsule Luminescent CsCl

http://fukushima-is-still-news.over-blog.com/article-new-test- makes-cesium-glow-113739873.html

The Human Toll

• 249 people were contaminated. • 20 people were admitted to the hospital. • 4 of the casualties died within four weeks of their admission to hospital.

• The post-mortem examinations showed hemorrhagic and septic complications associated with the .

• The best independent estimates of the total body radiation doses of these four people, by cytogenetic analysis, ranged from 4.5 Gy to over 6 Gy.

Uncontrolled Industrial source, Ir192

INTERNATIONAL ATOMIC ENERGY AGENCY, The Radiological Accident in Yanango, , IAEA, Vienna (2000). Industrial Radiography Industrial radiography is used throughout the world to examine the structural integrity of materials in a non- destructive manner.

https://www.ansndt.com/standard-ndt-services/radiography/

http://sitasndt.com/radiographic-testing/#1474863856061-3beab139-e78e

https://www.magnumndt.com/an-introduction-to-industrial- radiography-2019-blog

Housing Container ‘Camera’ Ir192 ‘Pigtail’

The incident

Day 2

• The source became detached from the ‘camera’. • At 4pm, a welder picked up the unshielded source with his right hand and placed it in the back right pocket of his trousers • At 9pm he felt a pain in the back of his right thigh. • At 10:30pm he complained to his wife about the pain and she looked at his posterior right thigh and noted a red area of skin. The incident continued

He took off his jeans and, with the source still in the pocket, placed them on the floor. He visited a local doctor who told him he had an "insect bite" and that he should put a hot compress on the area. The welder's wife meanwhile spent about five to ten minutes squatting/sitting on his jeans while she breastfed their 18 month old child. T Two other children who were at home, a girl of ten and a boy of seven, were about two to three meters from the source for approximately two hours.

Footer 46

Imaging

Day 6: Scout CT Day 6 MR

Footer 47

Day 23 Day 297

Footer 48 Family

Day 240: Ulcerative lesion on the lower back of the patient's wife. Day • The patient's wife showed moist desquamation, ulcerative and fibrotic lesions in the lower back after her brief exposure to the source while sitting on her husband’s jeans • No hematological changes were observed in her or her children.

Footer 49

Could this happen here?

Resources

IAEA website – accidents and exposures • https://www.iaea.org/publications/8117/the-radiological- accident-in-nueva-aldea • Report No. 161 II - Management of Persons Contaminated With : Scientific and Technical Bases (2008) • NRC Event notification: https://www.nrc.gov/reading- rm/doc-collections/event-status/ Backup Slides

ALS Safety

The ALS is a 3rd generation and is designed to produce very powerful beams of ionizing radiation. For accelerators such as the ALS, the most important (safety) components are shielding and interlocks. The Radiation Safety System (RSS) controls shutters which allow radiation into the beamlines. For personnel safety, these shutters are interlocked to ensure that no one can be exposed to the radiation. Accelerator shielding consists mainly of (permanent) concrete blocks.

ALS Beamlines Radiation Safety Systems

Interlock System shielding

Shielding (cont'd.)

Also includes beamline components that contain envelope such as bellows, pumps, piping, etc.

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What is the single largest source of ionizing radiation exposure in to the public? A) Radon B) Cosmic C) Medical x-rays D) Occupational Basic ionizing radiation control measures include which of the following:

A)Minimize time of exposure B)Increase distance C)Use shielding D)All of the above

Effects of acute radiation exposure on the central nervous system can be observed at doses of: A)10 Gray B)5 Gray C)2.5 Gray D)1.25 Gray