Alternative test methods
The term "alternative" is generally associated with the Principles of the 3Rs, - Replacement, Reduction and Refinement - of animal testing. In this context an alternative method serves to fully replace an animal test, to reduce the number of animals needed in a test, or to refine an animal testing procedure in order to reduce pain and suffering.
In vitro test methods use (reconstructed) tissues, whole cells or parts of cells. Recent advances in cell-based research include the development of two-dimensional and three-dimensional cell (co)-cultures which mimic very closely cells and tissues in the human body.
The growing use of 'omics' technologies (e.g. transcriptomics, proteomics and metabonomics) in combination with in vitro test systems allows a comprehensive analysis of the impact of a chemical at the molecular level and can indicate potential toxicity pathways that may lead to adverse health effects.
Computer-based approaches (often termed in silico or non-testing methods) are becoming increasingly powerful and can be used effectively to predict the toxicity of a chemical from its basic properties. Computer models are also an important tool for efficiently integrating toxicological information derived from complimentary in vitro and in silico methods.
A non-testing approach frequently used in the safety assessment of industrial chemicals, for example, is called 'read-across' technique where toxicological effects for one chemical are predicted using data for the same toxicological effect from another chemical, which is considered to be similar in terms of chemical structural, physico-chemical properties, or bioactivity.
Source: EURL ECVAM.