<Tr> <Td> Application of radium and thorium </Td> </Tr> <Tr> <Td> Other exposure situations </Td> </Tr> <Tr> <Td> Man - made sources </Td> <Td> Peaceful purposes </Td> <Td> Nuclear power production </Td> </Tr> <Tr> <Td> Transport of nuclear and radioactive material </Td> </Tr>

Which is the most susceptible to damage from ionizing radiation