Description

The dependence between radiation and chemical toxicity effect and the amount of radiation or chemical agent in human organs, tissues and whole body.

Category

Categorisation as a Feature, Event and/or Process.

  • Features are physical components of the disposal system and environment being assessed. Examples include waste packaging, backfill, surface soils. Features typically interact with one another via processes and in some cases events.
  • Events are dynamic interactions among features that occur over time periods that are short compared to the safety assessment timeframe such as a gas explosion or meteorite impact.
  • "Processes" are issues or dynamic interactions among features that generally occur over a significant proportion of the safety assessment timeframe and may occur over the whole of this timeframe. Events and processes may be coupled to one another (i.e. may influence one another).

The classification of a FEP as an event or process depends upon the assessment context, because the classification is undertaken with reference to an assessment timeframe. In this generic IFEP List, many IFEPs are classified as both Events and Processes; users will need to decide which of these classifications is relevant to their context and its timeframes.

  • Process

Relevance to Performance and Safety

The “Relevance to Performance and Safety” field contains an explanation of how the IFEP might influence the performance and safety of the disposal system under consideration through its impact on the evolution of the repository system and on the release, migration and/or uptake of repository-derived contaminants.

This FEP relates specifically to dosimetry and biokinetics in humans for any repository-derived contaminants that might reach the biosphere.

Doses from radioactive contaminants depend on factors that include the exposure mode (e.g. internal or external exposure), the metabolism with regard to the radiotoxic substance, the residence time in the tissue or organ, the energy and type of radioactive emissions of the radionuclide and any progeny, the age of the human at exposure and the lifetime commitment to the exposure.

Similar comments apply to chemotoxic effects, except that chemical and biochemical disruption of cell functions, not radioactive emissions, affect the tissues of the body. The chemical form of a compound plays an important role in determining whether and how the toxic component interacts with cells and tissues.

2000 List

A reference to the related FEP(s) within the 2000 NEA IFEP List.

3.3.05

Related References