The CAUSE of the Mad-Cow Problem
Zoltan Cseko
The Chernobyl accident occurred at 01:23 hr on Saturday, 26 April 1986, when
the two explosions destroyed the core of Unit 4 and the roof of the
Chernobyl reactor building.
During the first 10 days of the accident when important releases of
radioactivity occurred, meteorological conditions changed frequently,
causing significant variations in release direction and dispersion
parameters. Deposition patterns of radioactive particles depended highly on
the dispersion parameters, the particle sizes, and the occurrence of
rainfall.
The largest particles, which were primarily fuel particles, were
deposited essentially by sedimentation within 100 km of the reactor. Small
particles were carried by the wind to large distances and were deposited
primarily with rainfall.
The radioactive plume was tracked as it moved over the European part of the
Soviet Union and Europe. Initially the wind was blowing in a north-western
direction and was responsible for much of the deposition in Scandinavia, the
Netherlands and Belgium and Great Britain.
In Britain, the first cases of the Mad-Cow Disease can be dated back to
1986, in the same year when the Chernobyl accident occurred.
The ingestion of radionuclides in food is one of the pathways leading to
internal retention and contributes to human exposure from natural and
man-made sources. Excessive contamination of agricultural land, such as may
occur in a severe accident, can lead to unacceptable levels of radionuclides
in food.
The radionuclide contaminants of most significance in agriculture are those
which are relatively highly taken up by crops, have high rates of transfer
to animal products such as milk and meat, and have relatively long
radiological half-lives.
However, the ecological pathways leading to crop contamination and the
radioecological behaviour of the radionuclides are complex and are affected
not only by the physical and chemical properties of the radionuclides but
also by factors which include soil type, cropping system (including
tillage),climate, season and, where relevant, biological half-life within
animals.
The major radionuclides of concern in agriculture following a large
reactor accident are iodine-131, caesium-137 (half-life: 30 years),
caesium-134 and strontium-90 (half-life: 90 years). Direct deposition on
plants is the major source of contamination of agricultural produce in
temperate regions.
In the United Kingdom, restrictions were placed on the movement and
slaughter of 4.25 million sheep in areas in south-west Scotland, north-east
England, north Wales and northern Ireland.
This was due largely to root
uptake of relatively mobile caesium from peaty soil, but the area affected
and the number of sheep rejected are reducing, so that, by January 1994,
some 438,000 sheep were still restricted. In north-east Scotland, where
lambs grazed on contaminated pasture, their activity decreased to about 13
per cent of the initial values after 115 days; where animals consumed
uncontaminated feed, it fell to about 3.5 per cent.
The Chernobyl accident occurred 15 years ago, nevertheless the caesium-137
(half-life: 30 years) radionuclides and strontium-90 (half-life: 90 years)
radionuclides could be the most likely candidates for causing the Mad-Cow
Disease in cows and the Creutzfeldt-Jakob Disease in humans.
The scientific community is unaware of these facts partly because they
uninformed about the impacts of the Chernobyl accident partly because the
British Government isn’t concerned to initiate these kind of research.
This can be featured by that fact that the unknown Mad-Cow Problem and
Creutzfeldt-Jakob Problem was characterized by as a DISEASE instead of
POISONING.
However not a single fact shows that this problem is able to
transfer itself from one animal or human to another animal or human (except
by actually eating the poisoned animals).
Zoltan Cseko, PHD student at the Budapest University of Technics and Economy, Budapest, Hungary, Address: 1032 Budapest, Kiscelli utca 18. Tel: 3613880168
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