NERC-LV-539-18
RADIATION SURVEILLANCE OE  RUMINANTS  ON  AND ABOUT THE NEVADA TEST SITE
                                   by
                             Donald !.).  Smith
                     Radiological  Research  Program
                National  Environmental  Research Center
                 U. S.  ENVIRONMENTAL  PROTEC,   iN AGENCY
                            I -, "  V ,-,.-, -: r-   '.!,— , ,.J',
                              ihed
              This study  performed  under a Momoraridum of
                    Understanding  No.  AT(26-l}-539
                                 for the
                    U.  S.  ATOMIC ENERGY COMMISSION

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This report was prepared as an account of work sponsored  by  the United
States Government.  Neither the United States  nor the  United States
Atomic Energy Commission, nor any of their employees,  nor any of their
contractors, subcontractors, or their employees,  makes any warranty,
express or implied, or assumes any legal  liability or  responsibility
for the accuracy, completeness or usefulness of any information, apparatus,
product or process disclosed, or represents that  its use  would not infringe
privately-owned rights.
      Available  from  the  National Technical  Information Service,
                   U.  S.  Department of  Commerce,
                       Springfield, VA.  22151

              Price:  paper  copy  $3.00;  microfiche  $.95.
(JU1

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                                                                    NERC-LV-539-18
RADIATION SURVEILLANCE OF RUMINANTS ON AND ABOUT THE NEVADA TEST SITE
                                 by
                           Donald D. Smith
                    Radiological  Research Program
               National  Environmental Research Center

                U. S. ENVIRONMENTAL PROTECTION AGENCY
                          Las Vegas, Nevada
                       Published November 1972
             This study performed under a Memorandum of
                   Understanding No. AT(26-1)-539
                               for the
                   U. S. ATOMIC ENERGY COMMISSION

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                               ABSTRACT

The National Environmental Research Center-Las Vegas is engaged in various
radiation research and surveillance activities.  A portion of this work is
concerned with the metabolism and tissue burdens of radionuclides in domes-
tic and wild ruminants.

The 90Sr levels in bones from three species of ruminants grazing on or near
the Nevada Test Site have shown a steady decline since the cessation of
atmospheric testing in 1962.  Levels of 90Sr observed in desert bighorn
sheep (0\)jj> cana.de.W4A ne&on-t] ranged from 3.9-13.4 pCi/g of ash in 1964
(average of 9.7 pCi/g of ash) and from 1.0-12.0 pCi/g of ash in 1971
(average of 5.8 pCi/g of ash).

Levels of gamma emitting radionuclides found in the Nevada Test Site beef
herd remain low, with the liver as the edible organ containing the highest
levels of radioactivity.

In addition, the operation of an experimental dairy farm, the maintenance
of an experimental beef herd, and the use of the dairy herd in controlled
metabolism studies are discussed.

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                             INTRODUCTION

The National Environmental Research Center-Las Vegas (NERC-LV), is engaged
in various research and surveillance activities.  Much of this work is con-
cerned with the metabolism and tissue burdens of radionuclides in domestic
and wild ruminants.  This research requires three types of support activities
on the Nevada Test Site (NTS).  These are:  (1) the maintenance of an experi-
mental beef herd, (2) the conduction of wildlife surveillance, and (3) the
operation of an experimental dairy farm.

During 1957 an Animal Investigation Program was established by the Atomic
Energy Commission (AEC).  In 1964 this program was assigned to the NERC-LV.
The objectives of the Animal Investigation Program are:

     1.  To determine tissue concentrations of fresh and/or aged fission
     and activation products in biological samples obtained from bovine on
     the NTS and from off-site ranches, if required.

     2.  To develop and conduct wildlife studies on and near the NTS in
     cooperation with State and Federal wildlife agencies in order to.
     assess radionuclide content of various edible wildlife species.

     3.  To maintain veterinary relations with the off-site population.

     4.  To investigate alleged damage to domestic animals from the AEC's
     activities.

The research reported was performed as part of the Animal Investigation Pro-
gram and was supported by the U. S. Atomic Energy Commission under a Memo-
randum of Understanding.

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Experimental Beef Herd

Since 1957 a beef herd has grazed on the NTS * '.   The original herd was
purchased from area ranches.  The descendants of this herd now number
80 grade or nonpurebred Herefords.  They routinely graze the natural vege-
tation growing in the fallout zones of three atmospheric tests which were
detonated in the early sixties.  This herd is maintained in the same manner
as herds neighboring the NTS.

Twice a year the herd is rounded up and six beef animals are sacrificed.
The animals are necropsied and samples collected for radioanalysis and
histopathology.  No gross or microscopic lesions have been noted that can
be directly attributed to radiation ^2> 3'.  In 1970 the calving was 96%
and the average weight gain was 1.5 pounds per day between May and
October.

Table 1 presents a summary of the analytical data from the tissues collected
from beef animals grazing on the NTS that were sacrificed on October 29, 1970.
As shown in the table, certain radionuclides (95Zr, 106Ru) detected in the
ingesta in the ruminants are not readily absorbed through the gut but are
passed out of the animals in the feces.  The 131I levels found in the
thyroids are believed to have resulted from an atmospheric nuclear deto-
nation that was conducted by a foreign nation on October 14, 1970.  The
International Commission on Radiological Protection (ICRP) recommended
biological parameters and radiation protection guides in ICRP Reports 2
and 10.  Cesium is biologically similar to potassium, and is, therefore,
incorporated into the soft tissues of the body.  Thus, the radiation dose
from 137Cs is evaluated based on the total body dose.  The highest concen-
tration of 137Cs (80 pCi/kg) in an edible tissue was found in the liver of
one of the cattle.  Assuming an adult was to consume one pound of this liver
per week, for a year, his dose commitment could be calculated as shown
on page 4.

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Table 1.  Summary of Analytical Results of Tissues from Beef Animals,
	October 29, 1970 (reported on wet weight basis)	
                                                             Bone       Bone
           Rumen                                             Femur      Femur
Isotope   Content   Liver     Lung	Muscle   Thyroid   Wet Weight     Ash

K         0.8(7)    1.6(7)    1.3(7)    1.9(7)
g/kg      0.5-1.9   1.0-2.5   1.0-1.9   1.1-3.7    <0.3       NA      <   NA
            NA        NA        NA    "    NA        NA     1.0(7)       4.3(7)
pCi/g                                                      0.4-1.9     1.5-8.3
          45(5)     <25       <25       <25      <25          NA         NA
pCi/kg    45-50


106Ru     250(2)    <250      <250      <250     <250         NA         NA
pCi/kg    200-300


1311     <0.025     <0.025    <0.025    <0.025   6.2(6)        NA         NA
pCi/g                                            4.3-9.7


137Cs    <25         80(1)     230(1)    45(3)   <25          NA         NA
pCi/kg                                   30-50


144Ce     500(7)    300(3)    <250      <250     <250         NA   .      NA
pCi/kg    300-800   250-400	

First number is average, number in parenthesis is number of samples with
detectable activity, third set of numbers is the range.

NA = Not analyzed.

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     Dose Calculation
     80 pd/kg  x   -       x  1 ,bM  x
                                            yr
          _g   _                     ~
     x  ]. pCi  =  122 x TO"6  ~  =  o.i  mrem/yr of consumption.
This level of approximately 0.1 mrem would be about 'three orders of magni-
tude below the radiation protection guides recommended by the Federal  Radia-
tion Council and the ICRP.

Wildlife Surveillance

In addition to the beef surveillance, the Animal  Investigation Program is
charged with conducting surveillance of wildlife  which may enter the food
chain of man.  Samples are collected from at least one mule deer every
three months.  These samples are usually collected from road killed animals
but are occasionally hunted under the provisions  of a collection permit
issued by the Nevada Fish and Game Commission.  Rabbits and game birds are
also collected.

Samples from desert bighorn sheep are also collected through the cooperation
of personnel of the Desert National Wildlife Range and the participants in
the annual hunt in this area.  In recent years, the levels of gamma emitting
radionuclides in the tissues have been of low magnitude and are usually
below detectable limits of the Center's analytical equipment.

In the fall of 1970, water samples were collected from seven natural springs
on the Desert National Wildlife Range.  The results of gamma spectroscopy
analysis were negligible on all samples and the tritium levels did not
exceed 400 pCi/1.

Figure 1 presents the average 90Sr content of the ash of bones collected
from deer on or near the NTS, from cattle on the NTS and from desert bighorn
sheep on the Sheep Range.  The data presented were collected from 1964 to
1971.

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  20
 CD
 u.
CO
o

O
 Q.

I
CO


111
z
o
m
10
   0
                                                                  DEER

                                                                  BEEF

                                                        BIGHORN SHEEP
                                                          1=1
        1964
               1965
1966
1967
1968
1969
1970
1971
                               90
        Figure 1.   Comparison  of   Sr in Bones of Deer,  Beef and Bighorn Sheep

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The 90Sr data on the three species through 1963 were reported  previously
I '  '.  In general, all three species have shown a  downward trend since
1964 and this is assumed to be directly associated with the cessation  of
atmospheric testing in 1962.  In 1964 the range in bone ash samples from
desert bighorn sheep was 3.9-13.4 pCi/g of ash with  an average of 9.7  pCi/g
of ash and in 1971 the range was 1.0-12.0 pCi/g of ash with an average of
5.8 pCi/g of ash.

Strontium-90 has a long half-life (27.7 years) and resembles calcium in its
biological  behavior, so the critical  organ is bone.   As it decays by beta
emission, there may be damage to the  bone marrow, which is one of the  blood-
forming sites within the body.

Radiation protection guides have not  been specifically established for desert
bighorn sheep, but have been established for man. These standards may be
applied if it is assumed that desert  bighorn sheep are no more sensitive
to the effects of radiation than man.  The radiation protection guide  for
90Sr in man has been established by the National Committee for Radiation
Protection as 2 uCi in the critical organ, i.e. bone, for occupational
exposure.  The radiation protection guide for members of the general popu-
lation is l/30th of this value or 6.7 x lO4 pCi.  Standard man contains
7,000 grams of bone in his body which will yield approximately 2,330 grams
of ash.  For standard man 6.7 x lO4 pCi of activity  corresponds to 28 pCi
per gram of ash.

As shown in Figure 1, levels of 90Sr  found in the bone ash of  desert big-
horn sheep and other ruminants living on and around  the NTS  are a fraction
of the 28 pCi/g of ash level.

Experimental Dairy Farm

The experimental dairy farm was established in 1964  to study  the transport
of radioiodine through the soil-forage-cow-milk-food-chain.   Data obtained
from studies conducted there were used to formulate  a model  for calculating

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the dose to man drinking milk from cows exposed to fresh fission products
under a variety of conditions and exposure levels.

The research dairy farm is located in the northern end of the NTS, 120 miles
byroad from Las Vegas.  It consists of 16 1/2 acres of croplands which are
irrigated from a 5,400-foot well.  Crops grown are alfalfa and rye, which
furnish forage for the dairy herd of 30 animals (26 Holstein and 4 Jersey
cows).  Standard irrigation, fertilization, and harvesting practices are
used *  .  During 1970 the croplands provided 170 tons of green chop and
50 tons of hay.

The cows are maintained in a dry lot the year around.  They are not allowed
to graze; all forage is brought to them.  Commercial husbandry practices
are followed with the dairy herd, except that individual bucket milkers are
used to prevent cross contamination and to allow the collection of data from
individual cows.  The cows are milked on a 9- and 15-hour schedule, in order
                                   (7  8)
to reduce the manpower requirement v *   .

Despite the unusual milking hours and extensive participation in experi-
ments, the cows average over 13,000 pounds of milk per lactation with an
average butterfat percentage of 3.5.  The Nevada Dairy Herd Improvement
Association's monthly ratings have placed the herd as high as No. 1 on
butterfat percentage and third on milk production.

In addition to furnishing feed for the cows, the crops are used for experi-
mental purposes.  They were used for studying the uptake and retention of
radionuclides by the plants and for the investigation of the uptake of
radionuclides by the cows from ingestion of the plants.  Aerosols of
radioiodine were generated over the crops which were then harvested in the
normal manner.  A weighed amount of this forage was fed to the cows in the
experimental feeding pens.  A sample of each cow's ration was analyzed for
radionuclide content prior to feeding.   The uneaten residue was also
weighed and the total radionuclide intake of the .cow was determined.  At
each milking, each cow's production was weighed and sampled for analysis.
The percentage of the radionuclide transferred to the milk was then derived.

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Other experiments were carried out in association with Plowshare cratering
experiments.  Forage was placed downwind of these experiments and subse-
quently returned to the farm and fed in the same manner as  above, except
that baled hay was chopped before feeding to ensure that a  homogeneous ration
was fed and that a representative sample was collected.

There is a microplot area at the farm with 1/8 to 1/4 acre  study plots which
are used to grow a variety of forage, grain and vegetable crops.  The wheat
yield in 1970 was approximately 40 bushels per acre.   Vegetables that have
been grown include onions, radishes, potatoes, beets, sugar beets, lettuce,
Swiss chard, beans, English peas, cow peas, melons, sweet corn,  and tomatoes.
These plots have been used to study the uptake of aged radionuclides by the
crops from the soil which contains ejecta from the Sedan crater.  The leach-
ing effect of irrigation water on these radionuclides has also been studied.

The dairy cows have been used for metabolism studies  of various  radionuclides.
In these studies, following the oral or intravenous administration of the
selected radionuclide, the cows were placed in special metabolism stalls
for a period of 8 to 14 days.  During this time, milk and blood samples
were collected every six hours.  The entire fecal and urinary output was
collected and sampled every 12 hours and the thyroids were  counted period-
ically.  In this way the pathways of excretion for the radionuclide were
determined.  In addition, cull cows and steer calves  were given similar
doses and after varying periods of time they were sacrificed.  Each organ
and all tissues were sampled to determine the distribution  of the radionu-
clide within the body.  Radionuclides studied in this manner have included:
3H. 123I; 131I; 7Be. 181W; 202T1. 203Hg. 86Rb; 59Fe;  187W;  and 203pb>
                                   8

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                              CONCLUSION

The radionuclide burdens found in the tissues of domestic and wild rumi-
nants on and near the NTS continue the decline observed each year since
the cessation of atmospheric testing.  On the basis of guidelines currently
used, levels found present no significant hazards to the animals themselves
or to humans consuming their flesh.  Surveillance activities will be con-
tinued in order to determine any changes in the present situation.

Studies defining critical metabolic pathways of ingested radionuclides
which are likely to appear in the environment following nuclear detonations
provide valuable data for use in hazard evaluation.  Such studies are of
particular importance when conducted with dairy cows as dairy products con-
tribute a significant portion of the total diet for infants and children.

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                              REFERENCES

1.  Smith, D. D.  1970a.  Management Histoiy o&  the. AEC 8eei$ HeAd 1 Jane.
    1964 - 1 Jane. 1969.  SWRHL-80r.  Western Environmental  Research Labora-
    tory, Las Vegas, Nevada.
2.  Fountain, E. L.  1961.  0^-Site. Animal Investigation PAoje.ct
    Annual Re.poAt.  United  States Atomic  Energy Commission, Office Test
    Operations, Las Vegas Branch, Las  Vegas,  Nevada.
3.  Smith, D. D. and K. R. Giles.   1970.   Animal. Investigation
    1969 Annual Re.po*t.  SWRHL-102r.   Western  Environmental Research Labora-
    tory, Las Vegas, Nevada.

4.  Fountain, E. L.  1962.  Mu.dLe.aA. Test PiogAam as  it is ReŁate.d to the.
    VeseAt Bighoin Sheep.  Desert  Bighorn Council Trans.  6:62-67.

5.  Kramp, R. C.  1965.  PneJUminajiy  Re.poAt on 90St LeveŁa xln Hocfe. Joints
    o& VeseAt Bi.ahotin Sheep and Mule.  Ve.eA.   Desert Bighorn Council
    Trans. 9:87-92.

6.  Daley, E. M. and D. D. Smith.   1969.   Agronomic A&pe.cts o& the. Expe/u.-
    mental V&iny Fasun, January 1966 - Ve.cmbeA 1968.  SWRHL-63r.  Western
    Environmental Research Laboratory, Las Vegas, Nevada.
7.  Smith, D. D. and  R.  E.  Engel .   1969.   PAogiesA Re.poit Ł0*. tne. l$i.oe.n\j
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                               DISTRIBUTION

 1 - 20  National  Environmental  Research  Center, Las  Vegas, Nevada
     21  Mahlon E. Gates,  Manager,  NVOO/AEC,  Las Vegas, Nevada
     22  Robert H. Thalgott,  NVOO/AEC,  Las Vegas, Nevada
     23  Richard M. Pastore,  NVOO/AEC,  Las Vegas, Nevada
     24  Henry G.  Vermillion, NVOO/AEC, Las Vegas,  Nevada
     25  Donald W. Hendricks, NVOU/AEC, Las Vegas,  Nevada
     26  Elwood M. Douthett,  NVOO/AEC,  Las Vegas, Nevada
     27  Paul B. Dunaway,  NVOO/AEC, Las Vegas,  Nevada
     28  Ernest D. Campbell,  NVOO/AEC,  Las Vegas, Nevada
29 - 30  Technical Library ,  NVOO/AEC,  Las Vegas, Nevada
     31  Chief, NOB/DNA, NVOO/AEC,  Las  Vegas, Nevada
     32  Robert J. Catlin, Office of Environmental  Affairs, USAEC,  Washington,  D.C.
     33  Martin B. Biles,  DOS, USAEC, Washington, D.C.
     34  Tommy F.  McCraw,  DOS, USAEC, Washington, D.C.
     35  Assistant General Manager, DMA,  USAEC, Washington, D.C.
     36  Gordon C. Facer,  DMA, USAEC, Washington, D.C.
     37  John R. Totter, DBM, USAEC, Washington, D.C.
     38  John S. Kirby-Smith, DBM,  USAEC, Washington, D.C.
     39  L. Joe Deal, DOS, USAEC, Washington, D.C.
     40  Charles L. Osterberg, DBM, USAEC, Washington,  D.C.
     41  Rudolf J. Engelmann, DBM,  USAEC, Washington, D.C.
     42  Harold F. Mueller, ARL/NOAA, Las Vegas, Nevada
     43  Gilbert J. Ferber, ARL/NOAA, Silver  Spring,  Maryland
     44  Stanley M. Greenfield, Assistant Administrator for  Research & Monitoring,
         EPA, Washington,  D.C.
     45  William D. Rowe,  Deputy Assistant Administrator for  Radiation Programs,
         EPA, Rockville, Maryland
     46  Dr. William A. Mills, Dir., Div. of  Criteria & Standards,  Office of
         Radiation Programs,  EPA, Rockville,  Maryland
47 - 48  Charles L. Weaver, Dir., Field Operations  Division,  Office of
         Radiation Programs,  EPA, Rockville,  Maryland
     49  Ernest D. Harward, Act. Dir.,  Div.  of  Technology Assessment, Office of
         Radiation Programs,  EPA, Rockville,  Maryland

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Distribution (continued)

     50  Gordon Everett,  Dir.,  Office  of Technical Analysis, EPA,
         Washington,  D.C.
     51  Library,  EPA,  Washington,  D.C.
     52  Bernd Kahn,  Chief,  Radiochemistry & Nuclear Engineering, NERC, EPA,
         Cincinnati,  Ohio
     53  Kurt L.  Feldmann, Managing Editor, Radiation Data & Reports, ORP, EPA,
         Rockville, Maryland
     54  Dr. J. Frances Allen,  ORM, EPA, Arlington, Virginia
     55  Regional  Admin.,  Region  IX, EPA, San  Francisco, California
     56  Regional  Radiation  Representative, Region IX,  EPA, San  Francisco,
         California
     57  Eastern Environmental  Radiation Laboratory, EPA, Montgomery, Alabama
     58  William C.  King,  LLL,  Mercury, Nevada
     59  Bernard W. Shore, LLL, Livermore, California
     60  James E.  Carothers, LLL,  Livermore, California
     61  Howard A. Tewes,  LLL,  Livermore, California
     62  Lawrence S.  Germain,  LLL,  Livermore,  California
     63  Paul L.  Phelps,  LLL,  Livermore, California
     64  Charles I. Browne,  LASL,  Los  Alamos,  New Mexico
     65  George E. Tucker, Sandia  Laboratories, Albuquerque, New Mexico
     66  Harry S.  Jordan,  LASL, Los Alamos, New Mexico
     67  Arden E.  Bicker,  REECo,  Mercury, Nevada
     68  Savino W. Cavender, REECo, Mercury, Nevada
     69  Carter D. Broyles,  Sandia Laboratories, Albuquerque,  New Mexico
     70  Melvin L. Merritt,  Sandia Laboratories, Albuquerque,  New Mexico
     71  Richard S.  Davidson,  Battelle Memorial Institute, Columbus,  Ohio
     72  R. Glen Fuller,  Battelle  Memorial  Institute,  Las Vegas, Nevada
     73  Steven V. Kaye,  Oak Ridge National Lab., Oak  Ridge, Tennessee
     74  Leo K. Bustad, University of  California, Davis,  California
     75  Leonard A.  Sagan, Palo Alto Medical Clinic, Palo Alto,  California
     76  Vincent Schultz, Washington State  University,  Pullman,  Washington
     77  Arthur Wallace,  University of California,  Los  Angeles,  California
     78  Wesley E. Niles, University of Nevada, Las  Vegas, Nevada

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Distribution (continued)


     79  Robert C.  Pendleton,  University of Utah,  Salt Lake  City,  Utah

     80  William S. Twenhofel, U.  S.  Geological  Survey, Denver,  Colorado
     81  Paul R. Fenske,  Desert Research Institute,  University of  Nevada,
         Reno, Nevada
     82  John M. Ward, President,  Desert Research  Institute, University of
         Nevada, Reno, Nevada
83 - 84  Technical  Information Center,  USAEC,  Oak  Ridge, Tennessee (for
         public availability)

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