Book excerpt: At last – a second edition of this hugely important text that reflects the progress and experience gained in the last decade and aims at providing background and training material for a new generation of risk assessors. The authors offer an introduction to risk assessment of chemicals as well as basic background information on sources, emissions, distribution and fate processes for the estimation of exposure of plant and animal species in the environment and humans exposed via the environment, consumer products, and at the workplace. The coverage describes the basic principles and methods of risk assessment within their legislative frameworks (EU, USA, Japan and Canada).