134
The average annual radiation dose per person in the U.S. is 6.2 millisieverts and
most of the average annual dose comes from natural background radiation, with
radon and thoron together amounting to 37% of all natural radiation sources [16].
Radon is a chemically inert, naturally occurring, radioactive gas with no smell,
color, or taste, and is produced from the natural radioactive decay of uranium, which
is found in rocks and soil. Radon gas escapes easily from rocks and soils into the air
and tends to concentrate in enclosed spaces, such as underground mines, houses,
and other buildings. Exposure to radon at home and at the workplace is one of the
main risks of ionizing radiation causing tens of thousands of deaths from lung cancer each year globally [17]. Radon is the second most important cause of lung cancer after smoking and it is the primary cause of lung cancer among people who have
never smoked. Furthermore, based on current observations no reliable threshold
concentration below which radon exposure presents no risk can be defined [18].
Although radon is dangerous at high levels indoors, radon levels outdoor are
generally very low. Strategies to reduce exposure to radon involve increasing house
ventilation and performing radon measurements (with particular focus on quality
assurance and quality control measures) using dedicated devices such as alpha-track
detectors, electret ion chambers, activated charcoal detectors, electronic integrating
devices and continuous radon monitors.
Based on the latest scientific data, the proposed reference level to be used for
minimizing health hazards due to indoor radon exposure is 100 Bq/m
3
. If this level
is not reachable due to country-specific conditions, the chosen reference level
should not exceed 300 Bq/m
3
[18, 19]. Exposure to radioactive health hazard agents
has resulted from past nuclear weapons testing, nuclear waste disposal, accidents at
nuclear power plants, as well as from transportation, storage, loss, and misuse of
radioactive sources. While there are risks associated with exposure to radiation, the
benefits of nuclear applications in medicine, industry and science are well established. Noteworthy, research reviewing scientific studies linking radiation exposure
and cancer, published in a window spanning 40 years and covering over 300,000
nuclear workers from different countries, revealed that even the very lowest levels
of radiation are harmful to life [20]. This raises awareness for objectively evaluating
the benefits of radiation technology in comparison to the posed known risks. In this
context, the WHO’s radiation program is one of the international initiatives aiming
to assure that the benefits far exceed any known risks of the radiation technology.
8.5.2 Chemical Health Hazard Agents
Chemical hazards can cause acute or chronic adverse health effects, as consequence
of short- or long-term exposures. Manifestation of adverse effects range from skin
and eye irritation, to chronic diseases (affecting the heart, lung, brain or other
organs) and to cancer.
The top 10 categories of chemicals of major public health concern according to
WHO are: air pollution, arsenic, asbestos, benzene, cadmium, dioxin and
D. C. Schmid
The average annual radiation dose per person in the U.S. is 6.2 millisieverts and
most of the average annual dose comes from natural background radiation, with
radon and thoron together amounting to 37% of all natural radiation sources [16].
Radon is a chemically inert, naturally occurring, radioactive gas with no smell,
color, or taste, and is produced from the natural radioactive decay of uranium, which
is found in rocks and soil. Radon gas escapes easily from rocks and soils into the air
and tends to concentrate in enclosed spaces, such as underground mines, houses,
and other buildings. Exposure to radon at home and at the workplace is one of the
main risks of ionizing radiation causing tens of thousands of deaths from lung cancer each year globally [17]. Radon is the second most important cause of lung cancer after smoking and it is the primary cause of lung cancer among people who have
never smoked. Furthermore, based on current observations no reliable threshold
concentration below which radon exposure presents no risk can be defined [18].
Although radon is dangerous at high levels indoors, radon levels outdoor are
generally very low. Strategies to reduce exposure to radon involve increasing house
ventilation and performing radon measurements (with particular focus on quality
assurance and quality control measures) using dedicated devices such as alpha-track
detectors, electret ion chambers, activated charcoal detectors, electronic integrating
devices and continuous radon monitors.
Based on the latest scientific data, the proposed reference level to be used for
minimizing health hazards due to indoor radon exposure is 100 Bq/m
3
. If this level
is not reachable due to country-specific conditions, the chosen reference level
should not exceed 300 Bq/m
3
[18, 19]. Exposure to radioactive health hazard agents
has resulted from past nuclear weapons testing, nuclear waste disposal, accidents at
nuclear power plants, as well as from transportation, storage, loss, and misuse of
radioactive sources. While there are risks associated with exposure to radiation, the
benefits of nuclear applications in medicine, industry and science are well established. Noteworthy, research reviewing scientific studies linking radiation exposure
and cancer, published in a window spanning 40 years and covering over 300,000
nuclear workers from different countries, revealed that even the very lowest levels
of radiation are harmful to life [20]. This raises awareness for objectively evaluating
the benefits of radiation technology in comparison to the posed known risks. In this
context, the WHO’s radiation program is one of the international initiatives aiming
to assure that the benefits far exceed any known risks of the radiation technology.
8.5.2 Chemical Health Hazard Agents
Chemical hazards can cause acute or chronic adverse health effects, as consequence
of short- or long-term exposures. Manifestation of adverse effects range from skin
and eye irritation, to chronic diseases (affecting the heart, lung, brain or other
organs) and to cancer.
The top 10 categories of chemicals of major public health concern according to
WHO are: air pollution, arsenic, asbestos, benzene, cadmium, dioxin and
D. C. Schmid