Radiationhazards PPT

Tronko M, Brenner AV, Bogdanova T, et al. Thyroid neoplasia risk is increased nearly 30 years after the Chernobyl accident. International Journal of Cancer 2017; 141(8):1585–1588.

Recent studies have used genomic analysis of people affected by the Chernobyl accident to better understand how radiation exposure leads to cancer. In a 2021 study, investigators found that thyroid tumors in children who were exposed to fallout from the Chernobyl accident had higher levels of a particular kind of DNA damage that involves breaks in both DNA strands than tumors in unexposed individuals born more than 9 months after the accident (10). The more radiation the children had been exposed to, the more of this type of DNA damage was seen. This association was stronger the younger the children were at the time of exposure.

What can people do to protect themselves from health risks associated with exposure to contamination from a nuclear power plant accident?

Harmful effects ofradiationon environment

Researchers at NCI and elsewhere continue to learn about the cancer risks from ionizing radiation by studying various groups of people, including those who were exposed as a result of the Chernobyl accident, survivors of the atomic bomb explosions in Japan during World War II, and people who were exposed to radiation during medical diagnostic procedures or as part of their job.

Romanenko AY, Finch SC, Hatch M, et al. The Ukranian-American study of leukemia and related disorders among Chornobyl cleanup workers from Ukraine: III. Radiation risks. Radiation Research 2008; 170(6):711–720.

Another way in which radiation exposure could lead to cancer is through transgenerational effects, in which people exposed to ionizing radiation develop new genetic changes in their gametes (sperm or eggs) that are passed on to their future offspring, increasing cancer risk in those offspring. Transgenerational effects have been observed in some animal studies. However, genomic analysis of children born to people exposed to radiation at Chernobyl indicates that this exposure did not lead to an increase in new genetic changes in the children of exposed parents (11).

Although the time it takes for the radiation to decrease by half (the half-life) of I-131 is only 8 days, the damage it causes can increase the risk of thyroid cancer for many years after the initial exposure.

Children and adolescents can be more sensitive to the cancer-causing effects of ionizing radiation than adults because their bodies are still growing and developing. Also, children and adolescents usually have more years of life following radiation exposure during which cancer may develop.

Exposure to Cs-134 and Cs-137 can be external to the body or internal. External exposure comes from walking on contaminated soil or coming into contact with contaminated materials at nuclear accident sites. Internal exposure can come from breathing particles in the air that contain Cs-134 and Cs-137, such as dust originating from contaminated soil, or ingesting contaminated water or foods. Because Cs-134 and Cs-137 do not become concentrated in a particular tissue, the ionizing radiation that it releases can expose all tissues and organs of the body.

A study led by NCI researchers followed more than 12,500 people who were younger than age 18 at the time they were exposed to a range of doses of I-131 (0.65 Gy on average) from the Chernobyl accident (7). A total of 65 new cases of thyroid cancer were found in this population between 1998 and 2007. The researchers found that the higher a person’s dose of I-131, the more likely they were to get thyroid cancer (with each Gy of exposure associated with a doubling of risk). They also found that this risk remained high for at least 30 years (9).

Morton LM, Karyadi DM, Stewart C, et al. Radiation-related genomic profile of papillary thyroid carcinoma after the Chernobyl accident. Science 2021; 372(6543):eabg2538.

Local or national authorities may also advise certain people (newborns, infants, children, adolescents, and women who are pregnant) in areas with high I-131 contamination to take potassium iodide (KI) to prevent the accumulation of I-131 in their thyroid. KI should not pose a danger to someone who previously received radiation therapy or chemotherapy. Patients who are actively being treated for cancer and who are advised to take KI should consult with their doctor before taking the medication, so their doctor can evaluate their treatment plan and their health status, including their nutritional status, to determine the safety of KI treatment for them.

Power plant workers on-site at the time of the accident. Approximately 600 workers at the power plant during the emergency received very high doses of radiation and suffered from radiation sickness. All of those who received more than 6 grays (Gy) of radiation became very sick right away and subsequently died. Those who received less than 4 Gy had a better chance of survival. (A Gy is a measure of the amount of radiation absorbed by a person’s body.)

At high doses, ionizing radiation can cause immediate damage to a person’s body, including, at very high doses, radiation sickness and death. At lower doses, ionizing radiation can cause health effects such as cardiovascular disease and cataracts, as well as cancer. It causes cancer primarily because it damages DNA, which can lead to cancer-causing gene mutations.

The term “diverging mirror” is based on this mirror’s behavior of making rays diverge upon reflection. So when you direct a beam of light on a convex mirror, the mirror will allow the initially parallel rays that make up the beam to diverge after striking the reflective surface.

What is the first sign of too muchradiation

Much of what is known about cancer caused by radiation exposures from nuclear power plant accidents comes from research on the April 1986 nuclear power plant disaster at Chernobyl in Ukraine (Chornobyl in Ukrainian) (1, 2). The radioactive isotopes released during the Chernobyl accident included I-131, Cs-134, Cs-137, and Sr-90.

Everyone on Earth is exposed to low levels of ionizing radiation from natural and technological sources in varying proportions, depending on their geographic location, diet, occupation, and lifestyle.

Zablotska LB, Ron E, Rozhko AV, et al. Thyroid cancer risk in Belarus among children and adolescents exposed to radioiodine after the Chornobyl accident. British Journal of Cancer 2011; 104(1):181–187.

What can people do to protect themselves from health risks associated with exposure to contamination from a nuclear power plant accident?

A convex mirror is also a good security device. Store owners, for instance, install a number of them inside their stores and orient them in such a way that a single security personnel can see large portions of the store even while monitoring from a single location. They are the large disk-like reflective surfaces that you see near the ceilings of grocery or convenience shops.

The complete description of an image formed by a convex mirror is: virtual, diminished in size, and upright. When we say upright, we mean that if you position an arrow in front of this kind of reflecting surface, then the arrowhead of the reflection will point to the same direction as that of the object (the real arrow) itself.

Yeager M, Machiela MJ, Kothiyal P, et al. Lack of transgenerational effects of ionizing radiation exposure from the Chernobyl accident. Science 2021; 372(6543):725–729.

Human exposure to I-131 released from nuclear power plant accidents comes mainly from consuming contaminated water, milk, or foods. People may also be exposed by breathing dust particles in the air that are contaminated with I-131.

Radiationhazards PDF

Cancer patients who are being treated with systemic chemotherapy or radiation therapy should be evacuated from the area where a nuclear power plant accident has occurred so their medical treatment can continue without interruption. Patients should always keep a record of the treatments they have had in the past and that they may be currently receiving, including the names of any drugs and their doses. These records may be important in the aftermath not only of a nuclear power plant accident but also after other large-scale events that may disrupt medical services, when medical records may be lost.

If you would like to reproduce some or all of this content, see Reuse of NCI Information for guidance about copyright and permissions. In the case of permitted digital reproduction, please credit the National Cancer Institute as the source and link to the original NCI product using the original product's title; e.g., “Accidents at Nuclear Power Plants and Cancer Risk was originally published by the National Cancer Institute.”

Since convex mirrors have wider fields of view than other reflective surfaces, such as plane mirrors or concave mirrors, they are commonly used in automobile side mirrors. Having a fish eye on your automobile will allow you to see more of your rear.

Residents near Chernobyl. From 1986 through 2005, approximately 5 million residents of the contaminated areas surrounding Chernobyl received an accumulated whole-body average dose of around 0.01 Gy (6). Studies that have followed children and adolescents exposed to I-131 from the Chernobyl accident showed an increased risk of developing thyroid cancer (7–9).

Ionizing radiation consists of subatomic particles (that is, particles that are smaller than an atom, such as protons, neutrons, and electrons) and electromagnetic waves. These particles and waves have enough energy to strip electrons from, or ionize, atoms in molecules that they strike. Ionizing radiation can arise in several ways, including

The radioactive isotopes released in nuclear power plant accidents include iodine-131 (I-131), cesium-134 (Cs-134), and Cs-137. In the most severe kinds of accidents, such as the Chernobyl accident in 1986, other dangerous radioactive isotopes, such as strontium-90 (Sr-90) and plutonium-239, may also be released.

Cleanup workers. Hundreds of thousands of people who worked as part of the cleanup crews in the years after the accident were exposed to average external doses of ionizing radiation that ranged from approximately 0.14 Gy in 1986 to 0.04 Gy in 1989. Studies conducted in this group of people have found an increased risk of leukemia (3–5).

Radiationhazards and protection

Unlike images formed by concave mirrors, an image formed by a convex mirror cannot be projected on a screen. Such an image is called a virtual image. If one is to visualize the location of such a virtual image, then the image is found behind the surface of the mirror.

Inside the body, I-131 accumulates in the thyroid gland, which is an organ in the neck. The thyroid gland uses iodine to produce hormones that control how quickly the body uses energy. Because the thyroid does not distinguish between I-131 and nonradioactive iodine, the thyroid gland will accumulate either form. Exposure to radioactive iodine may increase the risk of thyroid cancer for many years, especially for children and adolescents.

Radiationhazard example

Nuclear power plants use energy released by the decay of certain radioactive isotopes to produce electricity. Additional radioactive isotopes are produced during this process. In nuclear power plants, specially designed fuel rods and containment structures enclose the radioactive materials to prevent them, and the ionizing radiation they produce, from contaminating the environment. If the fuel and surrounding containment structures are severely damaged, radioactive materials and ionizing radiation may be released, potentially posing a health risk for people. The actual risk depends on

United Nations Scientific Committee on the Effects of Atomic Radiation. Sources and Effects of Ionizing Radiation: UNSCEAR 2008 Report to the General Assembly with Scientific Annexes. Volume II, Annex D. Health effects due to radiation from the Chernobyl accident. New York: United Nations, 2011.

what are 5 harmful effects of radiation?

Zablotska LB, Bazyka D, Lubin JH, et al. Radiation and the risk of chronic lymphocytic and other leukemias among chornobyl cleanup workers. Environmental Health Perspectives 2013; 121(1):59–65.

Cardis E, Hatch M. The Chernobyl accident―An epidemiological perspective. Clinical Oncology 2011; doi: 10.1016/j.clon.2011.01.510.

The same kind of security devices are installed on automated teller machines to give the person withdrawing a good view of what is happening behind him. Some cell phones are also equipped with these mirrors to aid users when performing a self portrait shot.

Harmful effects ofradiationon humans

Want to read more about mirrors? Here are some articles from Universe Today featuring them: Parabolic Mirror Nano-Engineered Liquid Mirror Telescopes

Cardis E, Howe G, Ron E, et al. Cancer consequences of the Chernobyl accident: 20 years on. Journal of Radiological Protection 2006; 26(2):127–140.

A convex mirror is a spherical reflecting surface (or any reflecting surface fashioned into a portion of a sphere) in which its bulging side faces the source of light. Automobile enthusiasts often call it a fish eye mirror while other physics texts refer to it as a diverging mirror.

Hatch M, Ron E, Bouville A, Zablotska L, Howe G. The Chernobyl disaster: Cancer following the accident at the Chernobyl nuclear power plant. Epidemiologic Reviews 2005; 27:56–66. doi: 10.1093/epirev/mxi012

Brenner AV, Mykola DT, Hatch M, et al. I-131 dose-response for incident thyroid cancers in Ukraine related to the Chornobyl accident. Environmental Health Perspectives 2011; doi: 10.1289/ehp.1002674.

More information about the health effects of ionizing radiation exposure is available from the Centers for Disease Control and Prevention (CDC) and the Environmental Protection Agency.

Here are episodes from Astronomy Cast you might be interested in. Lend us your ears! Shooting Lasers at the Moon and Losing Contact with Rovers The Moon Part I

Want to see an object that is both a convex and a concave mirror? Take out a metallic spoon – the inner side is a concave mirror while the outer side is a convex mirror. Notice how your reflection is diminished in size. You may compare that with your reflection on a typical wall-mounted mirror.