Institute of Radiation Protection

Doses on the order of magnitude of 100 mSv could result from radiation exposure incidents in the workplace, accidents in nuclear establishments or from terrorist activities. In order to assess the risk of cancer connected with such incidents, relevant epidemiological data can be analysed with the help of carcinogenesis modeling. This type of modeling can also be applied to examine the influence of radiobiological effects, such as the bystander effect, genomic instability and radiation induced cell killing, on the radiation risks. Important cohorts for radiation epidemiology are the survivours of the atomic bombs in Hiroshima und Nagasaki, the workers of the Mayak Productions Association and the inhabitants of the Techa river. The thyroid cancer risk after the Chernobyl nuclear power plant accident is another area of reseach interest in the work group. A model including effects of radiation-induced genomic instability decribed best the breast cancer risk of the Swedish hemangioma cohort.

Homepage of Cancer risks from radiation exposure

Exposition of man to radiation in the past can be detected retrospectively by measuring the absorbed dose in materials of his environment or his body by means of physical methods. The exposition of crystalline materials to ionising radiation leads to the release of electrons that are catched in the crystal latice by so called 'electron traps' or by building up stable radicals. The absorbed radiation dose can be estimated by luminescence measurements of the trapped electrons or by measuring the paramagnetic resonance of the stable radicals. The workgroup risk analysis uses and develops the following techniques for dose reconstruction:

• Electron Paramagnetic Resonance (EPR) of teeth
• Luminescence (TL/OSL) of building materials, on body worn items and household materials

Homepage of Retrospective dosimetry

Radioecological models allow the quantification and analysis of exposures to ionizing radiations due to radionuclides in the environment. External exposure is caused from radionuclides in the soil or deposited on the ground (ground-shine) as well as from radioactivity in the air (cloud-shine). The incorporation of radionuclides into the human body with the consumption of food or inhalation of contaminated air causes internal exposures.

Radionuclides may enter the environment by gaseous or liquid discharges of e.g. nuclear facilities or from and medical facilities. Releases may occur during routine operation or accidental situations. Radionuclides are also released to the environment during mining and milling of uranium an as well as during mining of uranium.

The results of radioecological models are widely used for

• predictions of exposures and radionuclide concentrations in environmental media such as air, water, soil, food and feedstuffs,
• emergency management during nuclear accidents,
• identification of appropriate countermeasures for highly contaminated areas and assessment of the mitigating effect of remediation actions,
• in studies to reconstruct radiation exposures from radioactive releases to the environment in the past that led to enhanced exposures of specific collectives.

Homepage of Radioecological models

In our working group the biophysical Monte Carlo model PARTRAC has been developed and is being used for the in silico simulation of events occurring during and after the passage of ionising radiation through biological material. These investigations are primarily aimed at uncovering mechanisms leading to long-term radiation damage to cells, tissues and organisms.

Homepage of Biophysical models