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Properties of plasticsBackground radiation

Plastics are a group of important materials. They are long-chain molecules called polymers and can be made by joining many monomer units together in a process called polymerisation.

Part of ChemistryPlastics

Background radiation

Radiation is all around us. It comes from radioactive substances including the ground, air, building materials and food. Radiation is also found in cosmic rays from space.

The main sources of background radiation are in the table below.

Table showing sources of radiation: cosmic rays, animals, rocks, soil and plants.

Some rocks contain radioactive substances that produce a radioactive gas called radon. The pie chart below shows the average contribution of these different sources to natural background radiation.

Pie chart showing the various places background radiation comes from. These include radon gas, buildings, food and drink, cosmic rays and artificial sources.

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