PLUTONIUM
185
6. POTENTIAL FOR HUMAN
EXPOSURE
Muslyumovo were reported as 7 Bq/kg (200 pCi/kg), and 1.1 Bq/kg (30 pCi/kg) in the section from
Muslyumovo to Zarechnoye. These sites are in the area of the Mayak PA (Akleyev et al. 2000).
Børretzen et al. (2005) reported concentrations of 163 and 207 mBq/kg (4.41 and 5.59 pCi/kg) for
239
Pu
and 23 and 24 mBq/kg (0.62 and 0.65 pCi/kg) for
240
Pu in two dried grass samples from the Asanov
Swamp collected on June 26, 1994.
239
Pu and
240
Pu concentrations of 1,700 and 362 mBq/kg (46 and
9.78 pCi/kg) dry weight and 190 and 36 mBq/kg (5.1 and 0.97 pCi/kg) dry weight were also reported in
two samples of water plants, respectively (Børretzen et al. 2005)
Plutonium concentrations in moss samples from counties in Hungary were reported as 1.06 and
0.007 Bq/kg (28.7 and 0.2 pCi/kg) for
239,240
Pu and 2.39 and 0.011 Bq/kg (64.6 and 0.30 pCi/kg) for
241
Pu
in Komarom and Heves, respectively (Varga and Tarján 2008).
239,240
Pu concentrations in ashed fodder
(Pest), hay (Bacs-Kiskun), and sedge (Tolna) were reported as 1.91, 0.004, and 0.038 Bq/kg (51.6, 0.1,
and 1.03 pCi/kg), respectively.
241
Pu concentrations in these same samples were reported as 131, 0.22,
and 0.69 Bq/kg (3540, 6.0, and 19 pCi/kg), respectively (Varga and Tarján 2008).
6.5 GENERAL POPULATION AND OCCUPATIONAL EXPOSURE
The estimated 50-year dose commitment from plutonium for people in the north temperate zone
due to
atmospheric nuclear weapons tests conducted before 1973 is 0.2 mrad (0.002 mGy) to the bone lining
cells (Eisenbud 1987). The average annual dose equivalent from all background radiation to an individual
residing in the United States is estimated to be 360 mrem (3.6 mSv) (NCRP 1987).
Sanchez et al. (1999) reported that
239,240
Pu contributed the lowest dose of radionuclides studied in a
survey of the diets of individuals living in Cumbria, United Kingdom; the average dose was <0.04 µSv
(0.004 mrem).
Concentrations of
239,240
Pu in total diet samples collected from areas of the former
U.S.S.R. that were contaminated by fallout from Chernobyl ranged from 1.5x10
-7
to 7x10
-7
Bq/g
(4.1x10
-6
–2x10
-5
pCi/g) dry weight; a worst-case calculated dose of 0.2 µSv (0.02 mrem) was reported for
239,240
Pu (Cooper et al. 1992). Pietrzak-Flis and Orzechowska (1993) studied the content of
239,240
Pu in
daily diet samples collected from a hospital in Bialystok, Poland from March 1987 to May 1992. The
estimated annual intake of plutonium was 0.774 Bq/year (20.9 pCi/year) in the first year after the accident
at Chernobyl; after the sixth year, the daily intake was 0.088 Bq/year (2.4 pCi/year) (Pietrzak-Flis and
Orzechowska 1993). Daily ingestion of
239,240
Pu in food in Japan between 1978 and 1980 due to
atmospheric fallout was estimated to be 4.5x10
-3
pCi/day (1.7x10
-4
Bq/day) (Hisamatsu et al. 1987).
PLUTONIUM
186
6. POTENTIAL FOR HUMAN EXPOSURE
Filipy et al. (2003) reported plutonium concentrations in bone samples collect at autopsy from eight
individuals for the United States Transuranium and Uranium Registries (USTUR). The USTUR
documents levels and distribution of uranium and transuranium isotopes in human tissues for
occupationally exposed workers who donate their bodies to science (USTUR 2003). Plutonium levels
were measured in various bone samples: clavicle; patella; ribs (5–10); sternum; and vertebrae (T5–L3).
238
Pu concentrations ranged from 0.146 (clavicle) to 82.7 (sternum) Bq/kg (3.95–2,240 pCi/kg) dry
weight.
239
Pu concentrations ranged from 0.441 (patella) to 398.0 (vertebrae) Bq/kg (11.9–
10,800 pCi/kg) dry weight.
241
Pu concentrations ranged from 0.850 (sternum) to 25.2 (sternum) Bq/kg
(23–681 pCi/kg) dry weight (Filipy et al. 2003). Ivanova et al. (1995) measured
plutonium
concentrations in lungs, tracheobronchial lymph nodes (TLN), liver, and bone in 59 individuals who lived
in the areas of the Bryansk region of Russia that was contaminated by the Chernobyl accident. Average
concentrations of
238,239,240
Pu in lung, TLN, liver, and bone tissue were 0.060, 0.530, 0.070, and
0.070 Bq/kg (1.6, 14, 1.9, and 1.9 pCi/kg) dry weight, respectively (Ivanova et al. 1995).
Total plutonium deposition in five Manhattan Project workers exposed to plutonium in 1944–1945 ranged
from 98 to 3,300 Bq (2,600–89,000 pCi) according to autopsy data (Voelz et al. 1997). Mean
concentrations of
239,240
Pu in human tissues from autopsy specimens in Japan ranged from 2.5x10
-4
pCi/g
(9.3x10
-6
Bq/g) (cerebrum) to 1.5x10
-3
pCi/g (5.6x10
-5
Bq/g) (gonads) wet weight (Takizawa 1982).
Wrenn and Cohen (1977) reported
239
Pu levels in tissues derived from 12 autopsy cases
in New York City
from 1973 to 1976. Average levels for lung, liver,
vertebrae, and gonads were 2.4x10
-4
, 7x10
-4
, 1.7x10
-4
,
and 4x10
-4
pCi/g (8.9x10
-6
, 3x10
-5
, 6.3x10
-6
, and 1x10
-5
Bq/g), respectively. Tissue samples from autopsy
cases of nonoccupationally exposed individuals from Great Britain showed median
239,240
Pu
concentrations for ribs, vertebrae, femur, liver, and lungs of 1.6x10
-4
, 1.2x10
-4
, 9.5x10
-5
, 7x10
-4
, and
4.9x10
-5
pCi/g (5.9x10
-6
, 4.4x10
-6
, 3.5x10
-6
, 2.6x10
-5
, and 1.8x10
-6
Bq/g), respectively. Comparable
samples taken from autopsy cases from a region in Great Britain located near a plutonium processing
plant had median concentrations of 2.2x10
-4
, 1.9x10
-4
, 1.5x10
-4
, 1.4x10
-4
, and 1.8x10
-4
pCi/g (8.1x10
-6
,
7.0x10
-6
, 5.5x10
-6
, 5.2x10
-6
, and 6.7x10
-6
Bq/g) for ribs, vertebrae, femur, liver,
and lungs, respectively
(Popplewell et al. 1988).
Ibrahim et al. (1999) studied the excretion of
239
Pu in urine of residents living near the Rocky Flats
Environmental Technology Site (RFETS). The Rocky Flats group consisted of two groups of individuals
living near RFETS, who were not occupationally exposed to plutonium. Urine was collected from the
first group during 1992–1993 and samples were collected from the second group in 1995.
Background