While many places have high natural radiation, Iran (specifically Ramsar) hosts the world's highest measured natural background radiation levels due to radium-rich rocks, with residents receiving far higher doses than average, though other nations like India (Kerala/Orissa), China (Yangjiang), and Brazil (Guarapari) also have significant high background radiation areas (HBRAs).
Humans, animals and plants have been exposed to natural radiation since the creation of life, and levels of natural radiation can vary greatly around the world. Inhabited areas with high levels of natural radiation are found in Yangjiang China, Kerala India and Guarapari Brazil.
Average exposures to background radiation
In Australia, people receive about 1,500 to 2,000 μSv of ionising radiation every year. This is the level of natural background radiation in Australia. Low exposure to ionising radiation at this background level is not harmful.
The natural radionuclide radon, which is produced from the decay of uranium and thorium, is the largest natural source of exposure. Radon is a natural radioactive gas that gets into homes and buildings. It is important to test your home for radon to reduce your exposure to radiation.
The current area of approximately 2,600 km2 (1,000 sq mi) in Ukraine is where radioactive contamination is the highest, and public access and habitation are accordingly restricted.
Yes, Chernobyl is still highly radioactive in many areas, especially near the damaged reactor, but radiation levels vary significantly; some parts of the exclusion zone have contamination low enough for potential limited agriculture, while a 2025 drone strike damaged the New Safe Confinement (NSC) structure, raising concerns about long-term containment, although immediate levels stayed stable as the NSC's function is to contain the original sarcophagus's radioactive material, not the entire zone.
France has the greatest share of nuclear power in total electricity generation worldwide.
The city of Ramsar Iran hosts some of the highest natural radiation levels on earth, and over 2000 people are exposed to radiation doses ranging from 1 to 26 rem per year.
This notation is defined as Lethal Dose 50/30: the whole body acute dose that results in lethality to 50% of an exposed population within 30 days after irradiation.
Common sources of household radiation include granite countertops, vintage ceramics, glow-in-the-dark items, old televisions, cigarettes, and phosphate fertilizers, which all contribute to cumulative radiation exposure. Cosmic rays are a natural source of radiation exposure, continually bombarding Earth from space.
Australia experiences some of the world's highest UV Index levels, regularly exceeding 11 (extreme) in summer, especially in northern areas, reaching peaks of 12-14 and sometimes even 16-17, with values above 3 requiring sun protection for skin and eyes. These extreme levels occur due to clear skies and Australia's proximity to the ozone hole, making sun protection vital year-round.
Yes, it's true that EMFs produced by your Wi-Fi are reduced when you do things such as turn off your router and modem. Some people take the precaution of turning off their routers at periodic times, such as at night when they likely wouldn't want to use Wi-Fi, anyway.
Australia's known uranium resources are the world's largest – almost one-third of the world total. In 2022 Australia produced 4820 tonnes of U3O8 (4087 tU). In 2022 it was the world's fourth ranking producer, producing 8% of global uranium. All Australia's uranium production is exported.
10 of the World's Most Radioactive Places
Finland, for instance, has lots of granite in its ground. Granite contains considerable uranium levels. On average, a person living in Finland is exposed to 7.5 mSv (milliSievert) in background radiation, while someone living in the Netherlands is exposed to an average amount of 1.6 mSv per year.
Time, Distance and Shielding
Shielding: Barriers of lead, concrete or water provide protection from penetrating gamma rays and x-rays . This is why certain radioactive materials are stored under water or in concrete or lead-lined rooms, and why dentists place a lead apron on patients receiving x-rays of their teeth.
Enter a value in the 'Flight Time (hours)' field to calculate the effective dose in millisieverts (mSv). Our calculator uses an average radiation dose of 0.004 mSv per hour, based on data from Wikipedia. For example: A 7-hour flight results in a dose of 0.028 mSv.
Ramsar is a coastal city in northern Iran with some areas known to have the highest levels of natural background radiation in the world.
Radon gas poses a health risk not only to uranium miners, but also to homeowners if it is left to collect in the home. On average, it is the largest source of natural radiation exposure.
Iodine, strontium and caesium were the most dangerous of the elements released, and have half-lives of 8 days, 29 years, and 30 years respectively. The isotopes Strontium-90 and Caesium-137 are therefore still present in the area to this day. While iodine is linked to thyroid cancer, Strontium can lead to leukaemia.
The United States tops the list with 97 GW across 94 reactors. France ranks second at 63 GW, a result of its historic policy to standardize and scale nuclear after the 1970s oil shocks. China follows at 55 GW. Russia (27 GW) and South Korea (26 GW) round out the top five.
Nuclear power phase-out
By far the largest nuclear electricity producers are the United States with 781,945 GWh of nuclear electricity in 2024, followed by China with 417,518 GWh.