Radiations have always been a mysterious topic among people for ages, and the idea of invisible risk lurking in our surroundings is quite scary. But the question arises, how much radiation is dangerous? Let’s dive into the topic to find out more.
What is Radiation?
Before we discuss how much radiation is deadly, let us first comprehend what radiation means. In simple terms, Radiation refers to the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles that cause ionization. It occurs naturally and artificially in the environment. Even our bodies emit natural forms of radiation.
What are the Sources of Radiation?
There are two sources of radiations – Natural and Artificial. Natural Radiation comes from cosmic rays, radioactivity in rocks and soils, and radon gas. Artificial Radiation comes from medical uses, nuclear power plants, and nuclear weapon testing.
Natural Sources of Radiation
Natural Radiation can be divided into two types of radiation – cosmic and terrestrial radiation. Cosmic radiation includes solar and galactic radiation that originates outside our planet. This radiation roughly amounts to 8% of the total radiation exposure people receive each year. Terrestrial radiation, on the other hand, comes from radioactivity in rocks, soil, and even plants. Radon gas in the air contributes the most to the exposure of this type of radiation.
Artificial Sources of Radiation
Artificial Radiation includes industries and medical facilities that produce radioactive waste. Nuclear power plants for example, releases a small amount of radioactive material which moves along the air and then settles on the ground. Medical sources include X-rays, CT scans, and radiotherapy used for the treatment of cancer patients.
How Radiation Affects Our Body?
Radiation exposure that turns off our cellular functions and gives rise to a tumour is dangerous, but smaller doses that cause subtle or moderate cellular damage may not immediately result in illness. Exposure to high levels of radiation or repeated low-level exposure can cause cancer, decreased fertility, anemia, and birth defects. Radiation exposure can also weaken the immune system and speed up aging.
What are the Units of Radiation Dosage?
The International System of Units (SI Units) measures the radiation dose received by an individual, called the “Sievert” (Sv). The dose is proportional to the severity of the biological effect, and the frequency and duration of the exposure. Put differently; Genetic mutations usually result from around a single Sievert of radiation dose.
Units of Radiation Dosage Used:
- 1 millisievert (mSv) – 1000th of a sievert
- 1 microsievert (μSv) – 1 millionth of a sievert
- 1 nanosievert (nSv) – 1 billionth of a sievert
- 1 picosievert (pSv) – 1 trillionth of a sievert
How Much Radiation is Deadly?
Radiation can cause intense cell damage, which may result in cancer, organ dysfunction or death. In general, the following values apply;
If a person has suffered mild exposure, such as one or two radiation treatments, they may have little to no symptoms of radiation sickness. That said, the radiation dose received should never exceed 50 millisieverts in a year. In most cases, the symptoms resolve within several hours with rest even when doses exceed 50 mSv. Adults given a dose of 50 mSv or higher have an increased risk of developing cancer.
Exposure to moderate levels of radiation may result in nausea, vomiting, and diarrhoea. Exposure to doses higher than 1 Sievert within a short period can be lethal. The average dose received from a single CT chest scan is around 7mSv; that is why medical professionals limit the number of radiological diagnostic tests administered to one individual to reduce the risk of radiation exposure.
Exposure to high levels of radiation doses above 8 Sieverts results in almost immediate incapacitation, followed by death within several days. Hence, radon remediation, nuclear power-plant design, worker training, and radiation monitoring play an essential role in radiation safety.
Radiation exposure can be dangerous, but the levels of exposure varies depending on dose, duration, and the body area exposed to the radiation. People exposed to high levels of radiation doses need immediate medical attention. Prevention is crucial, and strictly following safety protocol can reduce the risk of exposure.
Li, C. C. R., Larkey, E., & Blankenhorn, D. (2016). The radiation safety officer's guide to radiation safety. CRC press. Gupta, M., Gupta, P., Mazumdar, A., Puri, V., Datta, S., & Chatterjee, S. (2015). Feedback dose reduction from computed tomography pulmonary angiography: a quality improvement project. BMJ open, 5(5), e006420.
What are the natural sources of radiation?
- The Sun
- The Earth’s crust
- The atmosphere
- Radon gas
- Volcanic activity
What are the artificial sources of radiation?
- X-rays and CT scans
- Nuclear power plant
- Medical sources of radioactivity
- Nuclear weapon testing
- Radioactive waste by industries
What is the unit of radiation dosage?
The International System of Units (SI Units) measures the radiation dose received by an individual, called the “Sievert” (Sv).
How much radiation is deadly?
If a person has suffered mild exposure, the radiation dose received should never exceed 50 millisieverts in a year. Exposure to doses higher than 1 Sievert within a short period can be lethal. Exposure to high levels of radiation doses above 8 Sieverts results in almost immediate incapacitation, followed by death within several days.