Background radiation high in Kerala
Recently scientists of Bhabha Atomic Research Center (BARC) have conducted an all India study on radiation and published it in the Journal of Environmental Radioactivity.
Key findings of report –
- In some parts of Kerala, background radiation levels are almost three times higher than estimated. However, despite this, it does not pose a high level of health hazard.
- Background radiation is emitted from natural sources such as rocks, sand, or mountains. Radiation is generated from the disintegrated nucleus of an unstable element. It can be emitted from anywhere, including components of matter from inside our bodies.
- Gamma rays are a type of radiation that can pass through matter unhindered. Although highly energetic, they are harmless unless present in large enough concentrations.
- In fact, it is like the heat of a fire, which gives a pleasant feeling until a burning condition is created.
IAEA: Maximum Radiation Risk Level
- The International Atomic Energy Agency (IAEA) sets the maximum radiation risk level and it is also adopted by India’s nuclear power stations.
- According to the IAEA, public exposure should not exceed 1 milli-Sievert in a year. On the other hand, for those who work in the plant, it should not exceed 30 milli-sievert in a year.
- The present study found that the average natural background level of gamma radiation in India was 94 nGy/hr (nano gray per hour) (or roughly 0.8 millisievert (mSv) /year).
- The last such study, carried out in 1986, calculated such radiation at 89 nGy/hr. 1 gray is equal to 1 sievert.
High radiation level in Kollam
- The 1986 study recorded the highest radiation exposure of 3,002 nGy/year at Chavara in Kerala.
- In the current study, the level in Kollam district (where Chavara is located) was 9,562 nGy/hr, or almost three times higher. This is equivalent to about 70 milliGray per year, slightly more than the exposure of a worker at a nuclear plant.
- The reason for the high radiation level in Kollam is the monazite sand, which is high in thorium. This is part of India’s long-term plan for sustainable production of nuclear fuel for many years.
- In southern India, high levels of radiation are emitted from uranium deposits due to the abundance of granite and basaltic, volcanic rock.
Source – The Hindu
