radiation accidents 2 nd qatar international trauma care, disaster & emergency medicine...

Radiation Accidents

2nd Qatar International Trauma Care, Disaster & Emergency

Medicine Conformance April 7-11, 2004

Prof. Dr. M. I. Al-Jarallah

King Fahd University of Petroleum & Minerals

Dhahran, Saudi Arabia

9 April 2004Radiation Accidents 2Dr. M. I. Al-Jarallah

Radiation Accidents

1- Definition of Radiation Accident2- Sources of Radiation Accidents3- Types of Radiation Exposures4- Biological Effects of Radiation5- Acute Radiation Syndrome6- Evaluation of Radiation Accidents7- Worldwide Radiation Accidents and

Illicit Trafficking8- Prevention of Radiation Accidents


Radiation Accidents

1- Definition of Radiation Accident

a. Accident is defined as an unintentional or unexpected happening that is undesirable or unfortunate, especially one resulting in injury, damage, harm or loss.

b. Radiation accident here can be defined as a situation which results in any unplanned radiation exposure or any unplanned release of radioactive material leading to radiation exposure.


Radiation Accidents

2- Sources of Radiation Accidents

Sources of radiation can be categorized as follows:

a. Sealed or encapsulated sources

b. Unsealed sources

c. Machine producing radiation


Radiation Accidents

Routinely used in the field in road construction and similar applications

Contain both a gamma-ray source and a neutron source

0.3 GBq 137Cs

1.5 GBq 241Am/Be

About 30 are stolen each year in the USA alone; only 40% are recovered

Moisture-Density Gauges


Radiation Accidents

Alpha - Sources: 241Am, 239Plutonium, 226Radium

Activity: kBq (µCi)

Smoke Detector


Radiation Accidents

Contain 0.1-5 TBq of 60Co, 192Ir, or 137Cs

About 1000 times more radioactivity than moisture density gauges

Radiography Sources


Radiation Accidents

Radioisotope thermoelectric generator (1000 TBq 90Sr)

Teletherapy unit(500 TBq 60Co)

Food irradiator400 000 TBq 60Co

High-intensity Sources


Radiation Accidents

Radiation accidents can arise mainly from problems with:

A. Nuclear ReactorsB. Industrial SourcesC. Medical Sources

These accidents arise because of:a. Loss of shielding, resulting in high radiation levels.b. Loss of containment resulting in a release of

activity.c. An uncontrolled criticality, which is, effectively, the

rapid generation of a large radioactive source and high levels of radiation.


Radiation Accidents

3- Types of Radiation Exposures

a. External Exposure.

b. Contamination with Radioactive Sources.

c. Combination of the above two.

Contamination is defined as unwanted radioactive material on in the body


Radiation Accidents

4- Biological Effects of RadiationHow Radiation can Lead to Damage in Tissue

Radiation

Electrical Effect (Ionization)

Physical & Chemical Changes

Damage to DNA

Cell Death Cell Transformation

Early Effect Cancer

Hereditary Defects


Radiation Accidents

5- Acute Radiation Syndrome For Gamma Radiation to the whole body

Dose (Gy) Symptoms Remarks

0 – 0.25

0.25 – 1

1 – 3

3 – 6

> 6

None

Mostly none. A few persons my exhibit mild prodromal symptoms, such as nausea and anorexia

Mild to severe nausea, malaise, anorexia, infection.

Severe effects as above, plus hemorrhaging, infection, diarrhea, epilation, temporary sterility

Above symptoms plus impairment of central nervous system; incapacitation at doses above ~ 10 Gy

No clinically significant effects

Bone marrow damaged; decrease in red and white blood-cell counts and platelet count. Lymph nodes and spleen injured; lymphocyte count decreases.

Hematological damage more severe. Recovery probable, though not assured.

Fatalities will occur in the range 3.5 Gy without treatment.

Death expected


Radiation Accidents

Incidents with very high-intensity sources have caused accidents involving people

unaware of what they were dealing with

Discarded teletherapyDiscarded teletherapysource in Thailand,source in Thailand,

~25 TBq Co-60~25 TBq Co-60Georgian woodsmen injured Georgian woodsmen injured by discarded 1500 TBqby discarded 1500 TBq Sr-90 RTG sources Sr-90 RTG sources


Radiation Accidents

6- Evaluation of Radiation Accidents The essential factor in evaluating the medical

consequences of radiation accidents includes information on the following:

a. External radiation (neutron, Xray or gamma radiation) and penetration.

b. Low-energy surface external reaction (beta radiation).

c. Initial surface contamination (important for evaluation of oral or transdermal intake of radionuclides).

d. Exposure to gaseous forms of radinuclides (eg. noble gases).


Radiation Accidents

7- Worldwide Radiation Accidents & Illicit Trafficking

0

5

10

15

20

25

30

35

40

1993 1994 1995 1996 1997 1998 1999 2000 2001

< 37 GBq

37-1000 GBq

> 1000 GBq

Incidents with Radioactive Sourcesgrouped for Activity


Radiation Accidents

Cs-13738%

Co-6012%

Am-24110%

Sr-9010%

Ra-2266%

Ir-1925%

Pu, Pu/Be4%

other15%

Cs-137

Co-60

Am-241

Sr-90

Ra-226

Ir-192

Pu, Pu/Be

other

Frequency of various Nuclides


Radiation Accidents

We can summarize the radiation accidents that resulted in radiation injury in medicine and industry in the following table:

Area of application Radionuclide Part of Body Expand

Medicine:

Diagnostics

Therapy

Industry:

Sterilization

Radiography

Gauging

Spent Sources

X – Ray generator 60Co,139Cs and accelerator

60Co,139Cs 192Ir,137Cs 192Ir,137Cs

60Co,137Cs

Hands, face,

whole body, hands and other parts

Whole body, hands

Hands, other parts

Hands, other parts

Hands, other parts


Radiation Accidents

8- Prevention of Radiation Accidents

The turning point in global interest of radiation safety and security problems was the International conference on Safety of Radiation Sources and Security of Radioactive Materials. The conference was cosponsored by the IAEA together with INTERPOL, the World Customs Organization, and the European Commission. It took place from September 14 to 18, 1998 in Dijon, France.

I quote here some of the major findings of the Dijon Conference, which are strongly related to our topic:


Radiation Accidents

a- Sources of ionizing radiation must have sufficient protection to allow for safe normal operations.

b- The possibility of accidental exposures involving radiation sources, must be anticipated and there must be appropriate safety devices and procedures. In this connection:


Radiation Accidents

i- weaknesses in the design and construction of radiation sources must be corrected;

ii- a high level of safety culture in the handling of radiation sources must be promoted, so that — inter alia — human errors are minimized through good training; and the concept of safety culture was to make it clear that safety should be the highest priority in organization handling radiation sources, which should be prepared to identify and correct problems promptly; that clear lines of responsibility should be established, not only for organization in handling sources but also in the governmental agencies controlling the use of sources. The lines of authority for decision making should be clearly defined.

iii- regulatory infrastructures for the control of radiation sources must be supported by governments and be able to act independently, and the regulatory authority in each country must maintain oversight of all radiation sources in that country.


Radiation Accidents

c- Radiation sources should not be allowed to drop out of the regulatory control system. This means that the regulatory authority must keep up-to-date records of the person responsible for each source, monitor transfers of sources and track the fate of each source at the end of its useful life.

d-Efforts should be made to find radiation sources that are not in the regulatory authority’s inventory, because they were in the country before the inventory was established, or were never specifically licensed or were lost, abandoned or stolen (such radiation sources are often referred to as “orphan” sources)


Radiation Accidents

Conclusion It is clear from these points that the key

common element is effective national regulatory authorities operating, within

suitable national infrastructures. Therefore:

a- Governments are urged to create regulatory authorities for radiation sources if they do not exist.

b- The government must provide it with sufficient backing and with sufficient human and financial resources to enable it to function effectively.


Radiation Accidents

Thank you

radiation accidents 2 nd qatar international trauma care, disaster & emergency medicine...

Documents