ML20009B392
| ML20009B392 | |
| Person / Time | |
|---|---|
| Issue date: | 11/16/1979 |
| From: | Levine S NRC OFFICE OF NUCLEAR REGULATORY RESEARCH (RES) |
| To: | Minogue R NRC OFFICE OF STANDARDS DEVELOPMENT |
| References | |
| RIL-073, RIL-73, NUDOCS 8107150358 | |
| Download: ML20009B392 (8) | |
Text
'
('~
g
/
- f-k UNITED STATES l ' l NUC1. EAR REGUI.ATORY COMMISSION
{-
j WASHINGTON. D C. 20555 o
k...[e glV 16 O
.p
~
IV 11Ef10RANDUf1 FOR:
Robert B. llinogue, Director Office of Standards Development FROM:
Saul Levine, Director Office of Nuclear Regulatory Research
SUBJECT:
RESEARCH INFORMATION LETTER # 73 - INVIVOCOU$TNIGAT SELECTED URANIUM MILLS This memorandum transmits the resultsi of completed research on the measurement of natural uranium deposited in the lung and radium deposited in the skeleton of workers at nine uranium mills. This work was perfomed by Helgeson Nuclear Services, Inc., under the direction of the Environ-mental Effects Research Branch of RES, in response to a request from your of fi ce.
!w The measurements of uranium lung burden and radium skeletal burden were perfomed at the mill sites in one of Helgeson Nuclear Services' mobile scientific laboratories. Two different whole body counters were used for the measurements.
For lung counting, a pair of 5-inch diameter phoswich detectors were held against the subject's chest by an elastic band which allows them to move up and down as the subject breathes in order to main-tain constant lung-to-detecter geometry. The radium is measured by an 8-inch diameter by 4-inch thick thallium activated sodium iodide detector which scans along the subject's body.
Calibration of the in vivo counting systems was perfomed by distributing radioactive sources with known activities inside standard phantoms and then perfomino the measurements exactly as is done for human subjects.
Because of the absorption of low ener0y photons, it was necessary to develop curves thich show the calibration factor for uranium as a function of chest thickness.
Calibration factors for radium were found to be quite insensitive to the positioning of the source.
Defining the minimum detectable activity (MDA) as three times the standard deviation of the background counting rate divided by the calibration factor, the limit of sensitivity for two phoswich detectort is 35 to 50 micrograms of uranium-235, which corresponds to 17 to 28 percent.
of the maximum pemissible lung burden. The limit of sensitivity for the 4'
thallium activated sodium iodide detector is 6 to 10 nanocuries of radium-226 dr or 6 to 10 percent of the maximum permissible body burden.
24 Ufd l Vivo Counting at Selected Uranium li n_ hTTTs, NUREG/CR-0841 s107150358 791136 PDR RES 8107150350 PDR
)
Robert B. Minogue Because of the low levels of activity deposited in the workers' bodies and the very high backgrounds due to the mill environment, data reduction involved complicated subtraction and curve fitting techniques.
Corrections vere made for cosmic ray interfercnces which are significant at the high altitudes there the mills are located.
Table 1.shows a representative sample of the different occupations involved and contains uranium and radium-226 results for each individual counted (identified by number and job title only) for one of the companies studied.
Table 2 presents ura:iium results by company in tems of the arithmetic mean and standard deviation as well as the geometric median and its standard devi ation. Table 3 presents radium-226 results in the same format. Table 4 presents the uranium results as a function of job title. The range of all uranium results is from a low of 0.8 mg to a high of 15.1 mg, while 'he mean of the population of 131 individuals is 5.6 + 3.5 mg at one standard deviation.
- of one to a high of 43nCi, while The range of all radium remits is from a lo the mean of the population of 127 individuals is 9.1 + 8.9 nCi at one standard devi ati on.
We recomend that the results presented in flVREG/CR-0041 be used by your staff in determining the value of taking in vivo measurements at mill sites. The RES technical contact for this work Ts Dr. Judith D. Foulke, Environmental Effects Research Branch (427-4358).
f i e Saul Levine, Director Office of fluclear Regulatory Research
Enclosure:
fiUREG/CR-0841
(
(
Subject Job Title Date & Time Uranium Radium 226 mg nCi
~
3 Tcld Operator 4/25/77 0 1609
- 7. 0 + 1. 6
~(1 )
4/25/77 0 1526
-ND-
.2 Metallurgist 4/25/77 0 1438 11.512.2 6
4/25/77 0 1356 1110 3
Maintenance 4/25/77 0 0745 4.1 + 1.'O 4/25/77 0 0703 01 7
4 Maintenance 4/25/77 0 1140
- 10. 7 + 1. 8 4/25/77 0 1156
-ND-5 Helper 4/25/77 0 1525 1 1. 0 +
1.
8 4/25/77 0 1441 9 1 10 6
Warehouseman 4/25/77 0 1001 7.: -+ 1. 4 4/25/77 E 0917 12 1 10 7
Pac kag e Ope r.
4/26/77 0 1038 11.911.6 4/25/77 0 0917 5110 8
Rip Operator 4/25/77 0 1454
- 13. 2 + 2. 2 4/25/77 0 1310
-ND-9 Maintenance 4/26/77 0 0921 2.4 1 1.4
-NC-(2) 10 Laborer 4/25/77 0 1742 4.4 + 0.8 4/25/77 0 1700 01 9 11 Maintenance 4/25/77 0 1224 8.9 + 1.8 4/25/77 0 1141 3110 12 Maintenance 4/25/77 0 0913 9.8 -+ 1. 8 4/25/77 0 0831 10 1 8
13 Chem Lab 4/25/77 0 1054 9.6 + 1.8 4/25/77 0 1010
-ND-14 Leach Operator 4/26/77 0 1154 9.7 + 1.6 4/26/77 0 1233 10 1 9 15 Mill Fo reman 4/25/77 0 1655 5.3 + 0.8 4/25/77 0 1611 16 + 12 i
Table 1 Company I
'In Vivo Counting Results i
--~-.y-
f
(
(
16 Rip Operator 4/26/77 e 1308
- 1. 0 ^ G. 8 4/26/77 e 1125 13 1 8
17 Leadman 4/25/77 e 1826 2.8 + 0.6 4/25/77 6 1743
-ND '
'._ EPR Operator 4/26/77 9 0725 3.610.8
,, 9
~
18 4/26/77 0 0700 13 1 19 Shifter 4/25/77 0 0830 9.8 + 1.2 4/25/77 0 0747 11 1 9
Leadman 4/26/77 0 0845 5.9 1 1.0 20
-NC-21 Rad. Supv.
4/26/77 0 0802 13.4 1 2.6
-NC-22 Mechanic 4/26/77 0 1118 6.0 1 0.7 4/26/77 0 1152
-NC-(1 ) Not Detectable (2) Not Counted Table 1 Continued Company I In Vivo Counting Results 4
9the oe
Company Number of Population Average 2-Sigma Ra ng e,
Number of Geometric,, '
Observations Arithmetic Measurement mg Observations Median and Standard Mean i 1-Sigma, Error, mg Deviation, mg mg s.
A 9
- 4. 2 + 2. 8
- 4.1 0.8 TO 10.1 9l' i 3.4, 2.2 e
6.8, 1.4 B'
14 7.1 + 2. 2 f 1.8 4.0 TO 11.0 14 C
13 4.9 + 3.3 11.2 1.5 TO 12.9 13 4.0, 2.0 2.7, 1.5 D
12 3.0 1 1.4 1 1.1 1.7 TO 6.8 12 E
18 3.6 + 1.9
+ 1.1 0.8 TO 7.3 18 3.1, 1.9 1.5 F
20 8.9 + 3.0
+ 2. 0 3.0 TO 14.0 20 8.3,,
G 13
- 3. 0 + 2.1
+ 1. 2 0.8 TO 8.6 13 2.5, 1.9 H
10
- 4. 2 + 4. 2 11.0 0.8 TO 15.1 10 3.0, 2.3
+ 1. 4 1.0 TO 13.4 22 6.6, 1.9 I
22 7.7 + 3. 7 Grand Mean or Med ian 131 5.6 1 3.5
+ 1. 3 0.8 TO 15.1 131 4.4, 2.1 The maximum permissible lung burden for natural uranium is 26 milligrams (Ref. 2).
Note:
Tabl e 2
Natural Uranium in Lung Detected by Measuring 234-Thorium Daughter of 238-Uranium
m-Company.
Number of Popula tion Average 2-Sigma Ra ng e,
Number of.-
Geometric
_, Observations Ar it hm et ic Measurment Nc1 Observations Median and Mean i 1-Sigma Error, NcI l'
i Standard NcI
, Deviation, NcI A
9 2.0 1 2.5 1 10 0 TO 6
6 2.2, 2.4 B
14 6.5 1 2.7
+ 7 1 TO 10 14 -
5.6, 1.8 C
14 9.0 1 12.1 1 10 0 TC 43 11 7.5, 2.r[N D
~
12 5.5 1 2.3
.1 9
1 TO 9
12 4.9,_1.8 E
18 16.4 1 6.5 1 9 0 TO 30 14 16.7, 1.3 F
19 5.5 1 5.9 1 6 0 TO 18
.14 6.0, 2.3 G
13 9.9 1 7.4 1 10 1 TO 29 13 7.0, 2.7 H
10 11.0 1 10,0 1 10 6 TO 24 7
14.5, 1.7 I
18 5.7 1 5.9 1 10 0 TO 16 11 7.7, 2.3 Grand Mean or Median 127 9.1 1 8.9 0 TO 43 108 7.6, 2.5 O
Note:
The maximum permissible body burden for industrial workers is 100 nanecuries.
Tabl e 3 226-Radium Results in Whole Body Determined by Least Squares Anal'ysis w
- 7..
Summary Number of Population Arithmetic Geometric Median-
- Range, Observations Mean i 1-Sigma, mg and Standard og Deviation, mg
~
Filherl Operator 1
5 10.014.4 8.84, 1. 8]. ' i 3.0 TO'14.0 2
Yellow Cake Operator 13 8.4 1 2.8 0.00, 1.46 4.0 TO 12.0 3
Lab Tech 10 6.3 1 4.4 5.17, 1.91 1.8 TO 13.4 4
Manag emen t 21 5.1 1 3.4 4.03, 2.11 -
0'.8 TO 13.0 5
Maintenance 24 5.1 1 2.8 4.34, 1.82
- 1. 5 TO 10. 7 6
Miscellaneous 13 5.0 1 2.7 4.26, 1.96 0.8 TO 11.0 7
Operator 28 4.913.4 3.89, 2.01 1.0 to 15.1 8
Cr0 sher 8
5.0 1 3.8 3.69, 2.47 0.8 TO 12.0 9
. Shifter 4
4.8 1 4.1 3.19, 3.09 0.8 TO 9.8 Note:
The maximum permissible body burden for industrial workers is 26 milligrams.
A Tabl e 4
Natural Uranium Results by Job Title I
a*
4
C C
Robert B. Minogue Because of the low levels of activity deposited in the worters' bodies and the very high backgrounds due to the stil environment, data reduction involved conplicated subtre:: tion and curve fitting techniques. Corrections wre made for cosmic re interferences which are significant at the high altitudes dere the allis am lecated.
7.ble 1 shows a rspresentative sample of the different occupations involved and contains uranium and radium-226 results for each individual counted (identified by number and job title only) for one of the companies studied.
Table 2 presents uranium results by company in terms of the arithmetic mean and standard deviation as well as the geometric median and its standard devi ation. Table 3 presents radium-226 results in the same format. Table 4 presents the uranium results as a function of job title. The range of all I
uranium results is from a low of 0.8 mg to a high of 15.1 mg, while the mean of the population of 131 individuals is 5.6 + '3.5 mg at one standard deviation.
The range of all radium results is from a low of one to a high of 43nC1, while the mean of the population of 127 individuals is 9.1 + 8.9 nCi a,t one standard deviation.
We recommend that the results presented in NUREG/CR-0841 be used by your staff in detemining the value of taking in vivo measurements at mill sites. The RES technical contact for this workTs Dr. Judith D. Foulke, Environmental Effects Research Branch (427-4358).
Original Signed By Saul Levine,
Saul Levine, Director Office of Nuclear Regulatory Research
Enclosure:
NUREG/CR-0841 DISTRIBUTION:
Subject File CHRON0 CIRC CBorrelli JFoulke FSwanberg, Jr.
JDavis 0Bassett FArsenault JLarkins RBudnitz l
Stevine l
See Previous Yellow for Concurrences
..[E.
F R:RESg IE5 RES MF
.AEER;RE enco hins sunmwc.-
,1 vj
Borrelli k
r la
.1/#/79._ id... _ II 4/79 x!..M9 1
/19.30/1/7._1M& /79 _ 10/27/79 1
c...__........_._............_....
,