20
General Features of Radioisotopic Methodology
public, despite the fact that all kinds of so-called radionuclides used in hydrobiological studies are in reality quite harmless both for the scientists using
them, and also for neighbors, colleagues, and the surrounding environment.
They all are the l3-emitters and are used in negligible amounts from the point
of view of radiation intensity. The radioisotopes of hydrogen 3H, carbon 14C
and sulfur 35S havc soft radiation which do as not penetrate the thin glass walls
of laboratory glassware and disappears in the air at a distance of 1-3cm from
the emitter. They are used in quantities of 1 to 20 microcuries on the laboratory desk, which under the sanitary radiation control regulations in Russia, for
example, is below the amount which comes under state control. Experimental
work with these radioisotopes in laboratories and on ships is permitted in ordinary common laboratories, with the same precautions as during work with
strong acids. After inserting the portions of working solutions of these
radioisotopes into experimental bottles or aquaria the concentration of
radioisotopes in them from the point of view of radioactivity norms is usually
less than is permitted for natural environments and products in respect of the
weak l3-emitters. Even to discover their presence, special sensitive detectors
are needed.
Concerning the use of radiolabeled phosphorus, its radioisotope, 33p, is the
same soft l3-emitter as 35S, for example, but more expensive. The use of 32p,
which is much cheaper but has a greater energy of its l3-radiation (see Table
1.1), also represents no possible health hazard when used for hydrobiological
research. This isotope is usually employed for labeling inorganic phosphate
P04P to study its biological turnover in the water column. Being used as a
tracer of a substance which is present in a minor amounts in water, it is used
in very small amounts - some 0.1-0.2 ~Ci per sample of 100-200ml. Thus, the
absolute radioactivity of 1 ml of water in the experimental sample will be only
about 2 x 10 3 dpm. This isotope does not contaminate surfaces because of its
short life time.
Students and scientists - the users of radioisotopes for hydrobiological
studies - should be convinced and also be able to convince their organizers,
neighbors, and the state authorities as to the harmless nature of the radioisotopes which are in use in this field, and as to the advantages of radioisotopic
methods for solving urgent ecological problems.
General Features of Radioisotopic Methodology
public, despite the fact that all kinds of so-called radionuclides used in hydrobiological studies are in reality quite harmless both for the scientists using
them, and also for neighbors, colleagues, and the surrounding environment.
They all are the l3-emitters and are used in negligible amounts from the point
of view of radiation intensity. The radioisotopes of hydrogen 3H, carbon 14C
and sulfur 35S havc soft radiation which do as not penetrate the thin glass walls
of laboratory glassware and disappears in the air at a distance of 1-3cm from
the emitter. They are used in quantities of 1 to 20 microcuries on the laboratory desk, which under the sanitary radiation control regulations in Russia, for
example, is below the amount which comes under state control. Experimental
work with these radioisotopes in laboratories and on ships is permitted in ordinary common laboratories, with the same precautions as during work with
strong acids. After inserting the portions of working solutions of these
radioisotopes into experimental bottles or aquaria the concentration of
radioisotopes in them from the point of view of radioactivity norms is usually
less than is permitted for natural environments and products in respect of the
weak l3-emitters. Even to discover their presence, special sensitive detectors
are needed.
Concerning the use of radiolabeled phosphorus, its radioisotope, 33p, is the
same soft l3-emitter as 35S, for example, but more expensive. The use of 32p,
which is much cheaper but has a greater energy of its l3-radiation (see Table
1.1), also represents no possible health hazard when used for hydrobiological
research. This isotope is usually employed for labeling inorganic phosphate
P04P to study its biological turnover in the water column. Being used as a
tracer of a substance which is present in a minor amounts in water, it is used
in very small amounts - some 0.1-0.2 ~Ci per sample of 100-200ml. Thus, the
absolute radioactivity of 1 ml of water in the experimental sample will be only
about 2 x 10 3 dpm. This isotope does not contaminate surfaces because of its
short life time.
Students and scientists - the users of radioisotopes for hydrobiological
studies - should be convinced and also be able to convince their organizers,
neighbors, and the state authorities as to the harmless nature of the radioisotopes which are in use in this field, and as to the advantages of radioisotopic
methods for solving urgent ecological problems.