The Riso National Laboratory in Roskilde Denmark has compiled a comprehensive data base of unclassified information about the dietary intake of radionuclides. In providing the following summary of Riso reports, RADNET would like to acknowledge and thank Asker Aarkrog and fellow researchers at the Riso Laboratory who collected this data. The following summary of Riso tabulations selects sea vegetables, milk, fish, tea and meat/eggs as well as total annual dietary intake for the radionuclide cesium 137 as an indicator of radioactive contamination from man-made sources. The Chernobyl accident and the high levels of contamination that resulted in locations outside Denmark illustrate the importance of the Riso database. In reviewing the following summary, the reader is urged to remember that Denmark escaped most of the impact of the Chernobyl accident, having received 1,210 Bq¹³⁷Cs m². In comparison, Chernobyl fallout in England and Wales reached levels exceeding 60,000 Bq ¹³⁷Cs m², in Sweden 100,000 Bq ¹³⁷Cs m² in scattered locations, and, in some areas downwind from Chernobyl in Byelorussia, contamination levels were measured in the hundreds of millions of Bq ¹³⁷Cs m². In the following summary, all data are averages unless followed by pv, meaning the peak value (peak concentrations) among a number of samples.
 

RADIOCESIUM DIETARY INTAKE BASELINE 
All data in Bq/yr. or Bq/kg and are mean values unless noted as peak values (pv). 

Location/yr.	Dietary Intake/yr.	Sea* Vegetables	Milk and Cream	Fish	Coffee/Tea	Meat
Greenland/1981	531.75	0.61	0.134	0.46	2.21	9.13
Faroes Is./1981	2,520.7	1.29	3.86	0.34	2.21	48.6
Denmark/1981	160.06	1.79 pv	0.134	5.70	2.21	0.36
Denmark/1982	153.55	15.6 pv	0.105	4.2	6.50 pv	0.38
Greenland/1982	651.66	3.1	1.05	0.28	2.53	11.16
Faroes Is./1982	1,887.8		3.33	0.26	2.53	24.6
Denmark/1983	103.24	11.6 pv	0.076	4.0	2.53	0.28
Greenland/1983	593.88		0.076	0.28	2.53	11.4
Faroes Is./1983	1,749.7		3.24	0.25	2.53	3.33
Denmark/1984	84.90	12.9 pv	0.085	14.5 pv	1.53	0.18
Greenland/1984	625.32	1.16	0.085	0.28	1.53	12.3
Faroes Is./1984	1,560.7	1.16	3.10	0.29	1.53	19.57
Denmark/1985	83.58	22 pv	0.076	3.15	1.53	0.25
Greenland/1985	856.06	1.56 pv	0.076	0.39	1.53	17.00
Faroes Is./1985	985.9	0.78 pv	1.82	0.29	1.53	11.34
Denmark/1986	483.57	33 pv	1.062	8.1 pv	1.29	1.16
Denmark/1987	571.54	18.1 pv	0.60	4.7	1.29	2.53
Greenland/1987	826.89		0.60	0.55	1.23	5.6
Faroes Is./1987	3,508.01	2.16 pv	5.85	0.63	1.29	53.8
Denmark/1988	153.44	60 pv	0.28	3.6	0.82	0.72
Faroes Is./1988	2,120.5	0.78 pv	2.77	0.44	7.3	24.1
Denmark/1989	171.14	21.4 pv	1.78	6.6	0.819	0.728
Faroes Is./1989	1,792.8	0.84 pv	1.89	0.36	7.3	22.6
Denmark/1990	177.62	25.0 pv	1.25	5.8	0.44	1.28
Greenland/1990	329.02		0.125	0.22	0.44	3.9
Faroes Is./1990	817.6	0.56 pv	1.61	0.23	0.44	6.64
Denmark/1991	146.73	26.0 pv	0.092	7.7	0.44	0.47
Greenland/1991	479.10		0.092	0.27	0.44	5.9
Faroes Is./1991	1196.9	1.36 pv	1.28	0.18	0.44	16.6

*dry weight

Several observations can be made about the data collected by the Riso National Laboratory. The yearly dietary intake of ¹³⁷Cs and its presence in the sea vegetables and market basket items cited in this chart vary widely, both before and after the Chernobyl accident. The Riso data document a modest increase in the dietary intake of cesium-137 in and after 1986. The question arises as to whether an expanded survey including imported and processed foods in Denmark after 1986 would document an even larger increase of Chernobyl-derived radiocesium similar to that documented by the FDA in the U.S.A. (See FDA peak pulse analysis at the end of this section). A yearly intake of 571.54 Bq of cesium-137 in Denmark in 1987 supports the argument that Denmark escaped the impact of the Chernobyl accident. The consistently low contamination levels in Danish tea and coffee help illustrate the significance of reports in RAD 10: Chernobyl Annotated Bibliography of Chernobyl-derived radiocesium in Turkish tea in the tens of thousands of becquerels per kilogram of brewed tea, to mention one example of the many citations of high levels of contamination in pathways to human consumption which resulted from the Chernobyl accident.

The following data has also been extrapolated from the Riso Reports and complements the dietary intake data cited above.
 

DATE

LOCATION

MEDIA

NUCLIDE

ACTIVITY*

*The following data express peak values unless otherwise noted.
 

1969-70	Greenland	Fucus vesiculosis	137Cs	35.6 Bq/kg
1969-70	Greenland	Fucus vesiculosis	239Pu	8.40 Bq/kg

• Sample taken near the impact of a B-52 carrying nuclear weapons which crashed near Thule, Greenland.

• Riso Reports note that 27% of cesium 137 in fish in Denmark originated from Sellafield, a nuclear fuel reprocessing facility located in Northern England on the Irish Sea and often noted as impacting dietary intake of radionuclides, particularly in the Faroes Islands. Further information on Sellafield as a source point of contamination is contained in RAD 11.

• The Riso Report also notes a peak value of cesium 137 in lichen carpet at 1,630 Bq/m2, with an estimated total accumulation of 2,400 Bq/m2 from stratospheric fallout.

• 13.3 km from the impact of the B-52 bomber crash.

• The above two citations are weapons-fallout radiocesium.
• 1985: The Riso Report notes that 85% of the ¹³⁷Cs content in Danish fish was Sellafield-derived. Without the contribution of Sellafield radiocesium the total dietary intake for 1985 would be 107.25 Bq of ¹³⁷Cs instead of 160.06 (See Riso, R-469, pg. 63).
• 1986: The Riso Report notes that in Denmark, an area relatively unaffected by Chernobyl fallout, the dietary intake of strontium 90 remained the same as the previous year, but levels of cesium 137 were 13.8 times higher than 1985 (Report no. Riso R-549, pg. 157).
• The report also notes a peak value of iodine 131 in stinging nettle at 670 Bq/kg and of cesium 137 at 200 Bq/kg. Mean concentration of cesium 137 in air increased by a factor of 2000 (Report no. Riso R-549, pg. 45).

The Riso reports cited in this section are: Riso R--470, 471, 487, 488, 489, 509, 510, 527, 528, 540, 549, 563, 564, 570, 571(EN), R-621(EN).

These summaries of data represent a pre-Chernobyl baseline for the dietary intake of radiocesium and provide a reference for the evaluation of the Chernobyl accident and its impact outside of Denmark.
 

3. BODY BURDENS

Following is a sampling of the many thousands of articles on body burdens of weapons tests fallout nuclides. For more citations on the impact of the Chernobyl accident, see RAD 10. This particular section of RADNET is cited in the order of the date of publication.

Liden, K. (1961). Cesium-137 burdens in Swedish Laplanders and reindeer. Acta Radiol., 56, 365-390.

Cohn, S.H., Spencer, H., Samachson, J., Fedlstein, A., Gusmano, E. (1962). Influence of dietary stable strontium and calcium on the turnover of bone-fixed ⁸⁵Sr in man. Proceedings of the Society for Experimental Biology and Medicine, 110, 526-528.

• Strontium-90 exhibits long-term retention once incorporated into bone.
• "The turnover time for strontium in some of the "long-term" compartments of bone may range up to values exceeding fifty years." (p. 528).

Naversten, J. and Liden, K. (1964). Half-life studies of radiocesium in humans. Assessment of Radioactivity in Man. (Report No. STI/PUB/84). Vienna: International Atomic Energy Agency.

Melandri, C. and Rimondi, O. (1964). In vivo measurement of ¹³⁷Cs with a human body counter. Assessment of Radioactivity in Man. (Report NO. STI/PUB/84). Vienna: International Atomic Energy Agency.

Rundo, J. (1964). A survey of the metabolism of cesium in man. Br. J. Radiol., 37, 108-14.

Ramsaev, P.V., Shamov, V.P., Troizkaj, M.N., Lebedev, O.V., Ibatulin, M.S. (1965). Indirect assessment of total body burden of ¹³⁷Cs in people. Medizinskaj Radiol, 6, 22-28.

Magno, P.J., Kauffman, P.E. and Shleien, B. (1967). Plutonium in environmental and biological media. Health Physics, 13, 1325-1330.
 

1965	Winchester, MA	human liver	239Pu	2.52 pCi/kg
1965	Winchester, MA	human lung	239Pu	1.13 pCi/kg

Boni, A.L. (1969). Variations in the retention and excretion of ¹³⁷Cs with age and sex. Nature, 222, 1188-9.

Karches, G.J., Wheeler, J.K., Helgeson, G.L. and Kahn, B. (1969). Cesium-137 body burdens and biological half-life in children at Tampa, Florida and Lake Bluff, Illinois. Health Physics, 16, 301-313.
 

October 1966	Tampa, Fl	Total Body Burdens - children	137Cs	7.7 nCi TBB (240 Bq)
October 1966	Lake Bluff, Ill	TBB- children	137Cs	3.4 nCi TBB (126 Bq)

Lloyd, D.R. Pendleton, R.C., Clark, D.O., Mays, C.W. and Goates, G.B. (1973). Cesium-137 in humans: A relationship to milk ¹³⁷Cs content. Health Phys., 24, 23-36.

Lloyd, D.R. (1973). Cesium half-times in humans. Health Phys., 25, 605-10.

Moghissi, A.A. and Mayes, M.G. (1973). Radiobioassay program of the institutional total diet sampling network III. Cesium -137 dose estimates and body burdens of children. Radiation Data and Reports, 14, 4, 233-236.

• Cesium-137 body burdens in children showed average concentrations of 4.4 nCi (4,400 pCi) in 1966; 2.3 nCi in 1967; and 2.0 nCi in 1968.

Lewis, J.T., Gossman, L.W., Kereiakes, J.G. and Saenger, E.L. (1976). Cesium-137 body burdens and half-life in a group of adult males in Cincinnati, Ohio. Health Phys., 30, 315-8.

Newton, D., Eagle, M.C. and Venn, J.B. (1977). The Cesium-137 content of man related to fallout in rain, 1957-76. Int. J. Environ. Stud., 11, 2, 83-90.

Glowiak, B.J., Pacyna, J. and Palczynski, R.J. (1977). Strontium-90 and caesium-137 contents in human teeth. Environ. Pollut., 14, 101-111.

• "The cesium-137 activity in deciduous teeth was, on average, 0.09 pCi/g of ash and, in permanent teeth, 0.05 pCi/g of ash." (p. 101).

Fisenne, I., Cohen, N., Neton, J., Perry, J. (1980). Fallout plutonium in human tissues from New York City. Radiation Research, 83, 162-168.

Szabo, A.S. (1980). Method for the theoretical determination of the biological half-lives of ¹³⁷Cs and ⁹⁰Sr in man, on the basis of K and Ca metabolism. Radiochem. Radioanal. Letters, 43, 4, 193-202.

Klusek, C.S. (1984). Environmental Measurements Laboratory: Strontium-90 in human bone in the U.S., 1982. EML-435. Department of Energy, New York, NY.

• One of many EML publications documenting weapons testing derived ⁹⁰Sr in the environment.
• Table 4 on page 18 summarizes the dietary intake of ⁹⁰Sr from 1954 to 1982; prior to the nuclear era, dietary intake of radiostrontium was zero. Peak intake of radiostrontium occurred in 1964 with ⁹⁰Sr intake levels reaching 29.8 pCi/gm of calcium in New York; ⁹⁰Sr intake in San Francisco generally runs 1/2 to 1/3 of that in the New York diet, New York being downwind from the Nevada Test Site. By 1982 ⁹⁰Sr intake had dropped to 5.6 pCi/gm of calcium in New York and 2.5 for San Francisco adults.
• Concentrations of ⁹⁰Sr in adult vertebra show a similar but slightly delayed pattern with peak values noted again from New York at 2.2 pCi/gm of calcium for bone concentrations. The San Francisco maximum value was 1.2 pCi/gm of calcium; vertebra concentrations show a much slower rate of decline than concentrations in milk: 1982 contamination levels in New York 1.2 pCi/gm of calcium.
• Other EML publications contain extensive data on ⁹⁰Sr as well as on other nuclides. Also see RAD 8: Baseline Data as well as publications of the Riso National Laboratory which contain the cumulative fallout record for ⁹⁰Sr.

• Cesium 137 body burdens in Norwegian Lapps declined between 1965 and 1975 with an apparent half-life of four to five years. After 1975, the decline was slower due to Chinese nuclear weapons tests' fallout.

Westerlund, E.A., Berthelsen, T. and Berteig, L. (1987). Cesium-137 body burdens in Norwegian Lapps, 1965-1983. Health Phys., 52, 171-7.

Gallelli, G., Orlando, P., Perdelli, F., De Flora, S., Malcontenti, R. and Bianchini, L. (1989). Assessment from autopsy sources of the internal dose due to ¹³⁷Cs and ¹³⁴Cs from the Chernobyl accident. J. Environ. Radioactivity, 9, 131-143.

Clemente. G.F., Mariani, A.& Santaroni, G.P. (1990). Sex differences in Cs-metabolism in man. Health Phys,. 23, 394-5.
 

June 1986 -June 1987	Genoa, Italy	Total Body Burden: Males	137Cs	1245 Bq TBB
June 1986-June 1987	Genoa, Italy	Total Body Burden: Females	137Cs	1017 Bq TBB

• These readings are less than some previously recorded pre-Chernobyl (fallout) body burdens. However, the Genoa area may have experienced much less of an impact from the Chernobyl accident than other areas of Italy. Due to the erratic Chernobyl fallout patterns, data from one location may not be interpreted as representative of any other location.

Hoshi, M. et. al. (1994). ¹³⁷Cs concentration among children in areas contaminated with radioactive fallout from the Chernobyl accident: Mogilev and Gomel Oblasts, Belarus. Health Physics. 67(3). pp. 272-275.
 

CHERNOBYL PEAK PULSE IN U.S.A. IMPORTED FOODS

Between May 5, 1986 and December 22, 1988, the FDA tested 1,749 samples of imported foods for levels of Chernobyl-derived radioactive contamination. From analysis of the results, it appears that the peak levels of Chernobyl-derived radiocesium in imported foods occurred approximately one year after the Chernobyl accident. Peak values are summarized below for the eight month period between February 1 and October 4, 1987 and for the five month period between February 5 and June 25, 1987, when contamination levels were highest.

Feb. 1 - Oct. 4, 1987

Total number of FDA samples of imported foods: 411

Number of samples with elevated levels of Cs-137:

183 samples with levels over 100 pCi/kg (44% of samples)

85 samples with levels over 1000 pCi/kg (20%)

19 samples with levels over 5000 pCi/kg (approx. 5%)

Feb. 5 - Jun. 25, 1987

Total number of FDA samples of imported foods: 161

Number of samples with elevated levels of Cs-137:

83 samples with levels over 100 pCi/kg (more than 50% of samples)

48 samples with levels over 1000 pCi/kg (almost 30% of samples)

11 samples with levels over 5000 pCi/kg (approx. 7%)

• In 1988, FDA survey data was still showing elevated levels of Cs-137 in imported foods. An Oct. 27, 1988, sample of macaroni from Greece contained Cs-137 levels of 11,100 pCi/kg (410 Bq/kg).
• Please contact us for a complete copy of the FDA survey which was classified at the time of its compilation and was only obtained after a freedom of information (FOI) request to the FDA.
• We have now scanned our copy of this report and can make it available to you as .jpg files that you may view by clicking the links below.  Our apologies for the fact some of this may not be as readable as we would like, but the originals were not done on a good copy machine.
• Pages: 1, 2, 3, 4, 5, 6, 7, 8, 9
• Pages: 10, 11, 12, 13, 14, 15, 16, 17, 18, 19
• Pages: 20, 21, 22, 23, 24, 25, 26, 27, 28, 29
• Pages: 30, 31, 32, 33, 34, 35, 36, 37, 38