[AC1] Over-exposure to Co-60 gamma-rays
.
Exposure: August 2, 1967. Tokyo
Subject: Medical doctor
Scenario: Over-exposure to 60Co gamma-rays due to the shutter trouble of tele-cobalt therapeutic macine.
Sampling: September 26, 1967.
ID Age Sex Physical estimate (mSv) No. of Aberrations Distribution of Dics+Rings
(yrs) Before After cells Tri Dic Rc Ra aM F del S del 0 1 2 3 4 5
29 M 0 16.9 1,275 0 1 0 0 2 5 4 2 2 1,274 1 0 0 0 0
Chromosomally estimated dose (cGy): 0 (0-2.98). .
.


 [AC2] Over-exposure to Co-60 gamma-rays
.
Exposure: June, 1967. Tokyo
Subject: RI worker
Scenario: Over-exposure to 60Co gamma-rays during unloading the cobalt source from an irradiator (Film badge reading was approximately 40 mSv)
Sampling: September 26, 1967.
ID Age Sex Physical estimate (mSv) No. of Aberrations Distribution of Dics+Rings
(yrs) Before After cells Tri Dic Rc Ra aM F del S del 0 1 2 3 4 5
25 M 0 40 838 0 0 0 0 0 3 3 3 3 838 0 0 0 0 0
Chromosomally estimated dose (cGy): 0 (0-4.32) .
.


 [AC3] Beta-ray accident
.
Exposure: March 30, 1968, Yokohama
Subject: Radiographer
Scenario: While setting the film for radiography using Betatron (peak voltage=15MVp, dose rate=1.35 Gy/min), the Betatron was switched on,
and exposed for 40-50 seconds. The calculated doses are a minimum 1.25 Gy to left hand and whole body dose was about 0.45 Gy.
Sampling: April 17, 1968.
ID Age Sex Physical estimate (mSv) No. of Aberrations Distribution of Dics+Rings
(yrs) Before After cells Tri Dic Rc Ra aM F del S del 0 1 2 3 4 5
25 M 450 1,000 0 0 0 0 0 4 4 2 2 1,000 0 0 0 0 0
Chromosomally estimated dose (cGy-equivalent): 0 (0-3.70) .
.


 [AC4] Over-exposures to gamma-ray
.
Exposure: July 15, 1971, Ibaraki
Subject: Nuclear power plant workers (Charge machine operators)
Scenario:During automatic housing of control rad from a charge machine, 3 operators were exposed to gamma-rays. Because the area monitor showed
the background radiation, the operators entered the room, where they found that the control rod was not completely housed into the housing
hole and they enforced in. The working time was 2-5 mins. Their personal dosimeters (maximum reading capacity of 200 mR) were over-scaled.
Radioactivity of the rod was 200 R/hr at 1 m. The exposure doses were estimated to be 9.42, 7.80 and 2.98 rem, respectivel, according to the
reconstruction of exposure scenario.
Sampling: August 10, 1971.
ID Age Sex Physical estimate (mSv) No. of Aberrations Distribution of Dics+Rings
(yrs) Before After cells Tri Dic Rc Ra aM F del S del 0 1 2 3 4 5
"A" 31 M 11.0 78.0 2,000 0 10 2 0 12 28 16 11 10 1,989 10 1 0 0 0
"B" 22 M 11.3 74.2 2,000 0 3 0 1 5 12 9 1 1 1,997 3 0 0 0 0 .
"C" 20 M 31.9 29.8 3,000 0 1 0 0 3 7 6 3 3 2,999 1 0 0 0 0
Chromosomally estimated dose (cGy): "A": 15.62 (9.03-23.90)
"B": 4.40 (0.47-10.43)
"C": 0 (0-0.42)
.


 [AC5] X-ray accident
.
Exposure: September 19, 1975, Tokyo
Subject: Radiographer
Scenario: Accidentally exposed to X-rays (50 kVp) during operation of X-ray fluoroscopy. Estimated doses were 20-30 Gy to the palms and
0.5-1 Gy to the body.
Sampling: September 30, 1975.
ID Age Sex Physical estimate (mSv) No. of Aberrations Distribution of Dics+Rings
(yrs) Before After cells Tri Dic Rc Ra aM F del S del 0 1 2 3 4 5
32 M 0 500-1000 2,000 0 3 0 0 0 4 2 3 2 1,997 3 0 0 0 0
Chromosomally estimated dose (cGy-equivalent): 2.63 (0-7.94) .
.


[AC6] High dose accidental exposure 
.
Subject: U. S. military man known to have been acidentally exposed to high level of radiation in 1956 and developed acute myerocytic leukemia
Blood sampling: 1965 (50-h lymphocyte culture), and direct preparation of bone marrow cells.
Reference: Norman, A., Sasaki, M. S., Ottoman, R. E., Veomett, R. C. (1967): Use of chromosome aberrations to estimate X-ray and gamma-ray dose to man. Report of the USAF School of Aerospace Medicine, SAM-TR-67-112, pp.1-18.
No. of cells Aberrant cells Chromosome aberrations No. of cells with: Distribution of cells with indicated number of dicentrics
analyzed Cu-cells Cs-cells* Dic cR aR M Ace Ace Dic+Ace M+Ace cR+Ace Dic+M+Ace M 0 1 2 3 4
370 2 12 4 2 0 22 11 0 0 0 0 2 12 368 0 2 0 0
*) The frequency of Cs-cells suggests the exposure to an equivalent whole body dose of 2-3 Gy.
.