The issue of how much soil and dust a child ingests is often central to exposure and health risk assessments conducted in the context of soil contamination. As a precautionary measure, the values used are often high. However, comparing calculated estimates of pollutant exposure doses with biomarker measurements reveals significant discrepancies, in which doses derived from the amount of soil ingested play a major role. Among the associated parameters, the bioavailability and bioaccessibility of pollutants in soil are also frequently cited as limitations of the studies. Addressing the combination of these two parameters was therefore essential. Under these circumstances, the French Institute for Public Health Surveillance (InVS) and the National Institute for Industrial Environment and Risks (Ineris) took the initiative, in 2007, to establish a working group (WG) to provide the necessary clarifications and analyses regarding this human exposure variable through a report summarizing current knowledge and proposals for the use of data on exposure and health risk assessment. Composed of experts with complementary expertise, this working group sought to draft an original, practical report that, on the one hand, summarizes the current state of knowledge in the form of a questionnaire addressing the most common questions and, on the other hand, proposes specific values and distributions for deterministic and probabilistic applications in exposure studies and health risk assessments. Finally, the outlook highlights the need for data on the amount of soil ingested at the national level and for expanding databases on bioaccessibility and bioavailability. (R.A.)