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12 Health Hazards and Protection
Damage to the cytoplasm is up to a point recoverable, provided the rate of damage
is less than the rate of recovery, whereas the damage to the nucleus could cause
mutation of genes in the chromosomes, which exist in a specific number of pairs i.e.,
23 in the human body. Mutation may change the characteristic of the cell or may
cause cell death. Sometimes the order of the genes is also changed, due to breakage
in the chromosomes. These may affect human characteristics e.g., colour of eye,
fall of hair etc. In short, radiation of any kind or energy causes a permanent damage
when it interacts with the nucleus.
Some tissues are more radio-sensitive than the others, such as bone marrow, in
which the red and the white corpuscles are produced. There are also tissues which
are little affected by radiations, such as skin, nail. Hence, hands, feet, ankles or other
parts of the body whose main constituents are skin and bone will be less affected by
radiations. In a tracer laboratory, especially in experiments in which nuclear radiation
with either neutron generator or laboratory neutron sources are used, the danger to
the body may be due to either external radiation or internal radiation (i.e., due to
ingestion of radioactive substances). The extent of the hazard depends upon the type
of radiation and the type of exposure.
While talking about the hazards of radiation to the human body, we shall have to
address it in two ways: (i) Are the radiations causing the damage to the cell externally
such that the rate of physiological equilibrium is affected. (ii) Or are these radioactive
isotopes chemically similar to chemicals, which follow the metabolic path and thus
retained by the human body either at a specific organ or throughout the body causing
damage to the physiological growth/decay process? The former effect is related to
the nature and energy of the radiations emitted by the radioactive isotopes, while
the latter is associated with the chemical nature of the radioactive isotopes. In a
biological system, therefore, the ionization of organic components of the cell by the
radiations can cause damage to the chemical composition of the cell, directly by
the disruption of chemical bonds in the cell, both in the cytoplasm and the nucleus.
Moreover, radiation of any kind or energy when interacts with the nucleus of the
human cell can cause permanent damage to the cell.
The effect of radiations on the human body can, therefore, be of two types: (i)
effect of radiation due to external radiations and (ii) effect of radiation of the isotopes
which are present inside the body due to some ingestion. The damage due to external
radiation depends naturally on the type of radiation and its energy. The internal
damage will depend upon the placement of the radioactive isotopes in the human
body. For example, some tissues of the human body are more radio-sensitive than
others, such as bone marrow, in which red/white corpuscles are produced and if the
isotopes are present in the vicinity of theses tissue, the damage would be of great
significance.
In a radiochemical laboratory, we, therefore, are likely to receive externally, radiations from a source like neutron generator or laboratory neutron sources or radiations
due to the handling of radioactive samples. These radiations either may be capable
of penetrating our body and causing damage to our cells within the body or may be
stopped by the skin of our body causing a local external damage to the body. The latter
is possible with sources like weak β-emitters or α-emitters. The damage done to the
12 Health Hazards and Protection
Damage to the cytoplasm is up to a point recoverable, provided the rate of damage
is less than the rate of recovery, whereas the damage to the nucleus could cause
mutation of genes in the chromosomes, which exist in a specific number of pairs i.e.,
23 in the human body. Mutation may change the characteristic of the cell or may
cause cell death. Sometimes the order of the genes is also changed, due to breakage
in the chromosomes. These may affect human characteristics e.g., colour of eye,
fall of hair etc. In short, radiation of any kind or energy causes a permanent damage
when it interacts with the nucleus.
Some tissues are more radio-sensitive than the others, such as bone marrow, in
which the red and the white corpuscles are produced. There are also tissues which
are little affected by radiations, such as skin, nail. Hence, hands, feet, ankles or other
parts of the body whose main constituents are skin and bone will be less affected by
radiations. In a tracer laboratory, especially in experiments in which nuclear radiation
with either neutron generator or laboratory neutron sources are used, the danger to
the body may be due to either external radiation or internal radiation (i.e., due to
ingestion of radioactive substances). The extent of the hazard depends upon the type
of radiation and the type of exposure.
While talking about the hazards of radiation to the human body, we shall have to
address it in two ways: (i) Are the radiations causing the damage to the cell externally
such that the rate of physiological equilibrium is affected. (ii) Or are these radioactive
isotopes chemically similar to chemicals, which follow the metabolic path and thus
retained by the human body either at a specific organ or throughout the body causing
damage to the physiological growth/decay process? The former effect is related to
the nature and energy of the radiations emitted by the radioactive isotopes, while
the latter is associated with the chemical nature of the radioactive isotopes. In a
biological system, therefore, the ionization of organic components of the cell by the
radiations can cause damage to the chemical composition of the cell, directly by
the disruption of chemical bonds in the cell, both in the cytoplasm and the nucleus.
Moreover, radiation of any kind or energy when interacts with the nucleus of the
human cell can cause permanent damage to the cell.
The effect of radiations on the human body can, therefore, be of two types: (i)
effect of radiation due to external radiations and (ii) effect of radiation of the isotopes
which are present inside the body due to some ingestion. The damage due to external
radiation depends naturally on the type of radiation and its energy. The internal
damage will depend upon the placement of the radioactive isotopes in the human
body. For example, some tissues of the human body are more radio-sensitive than
others, such as bone marrow, in which red/white corpuscles are produced and if the
isotopes are present in the vicinity of theses tissue, the damage would be of great
significance.
In a radiochemical laboratory, we, therefore, are likely to receive externally, radiations from a source like neutron generator or laboratory neutron sources or radiations
due to the handling of radioactive samples. These radiations either may be capable
of penetrating our body and causing damage to our cells within the body or may be
stopped by the skin of our body causing a local external damage to the body. The latter
is possible with sources like weak β-emitters or α-emitters. The damage done to the