This document has been developed to assist the decentralized offices of the Ministry of Health (particularly the DDASS) in compiling all available data to describe a situation of confirmed or suspected chronic industrial pollution. It is designed as a checklist, meaning it takes the form of lists of information that can be collected, in part or in full depending on the situation, for the purpose of assessing and managing the issue. The circumstances under which a decentralized unit of the Ministry of Health may be called upon to carry out this work are varied. This may be in response to: - complaints from a residents’ association or any other type of association with a stake in the matter - an environmental indicator: results of analyses of various environmental compartments suggesting that the population may be exposed to a chemical, microbiological, or physical agent that may pose a risk based on current scientific knowledge - a health-related indicator: reports of pathologies (in humans or animals) that are unusual in their frequency or severity and that could be attributable to industrial pollution; - knowledge of a former industrial site whose operations are likely to have caused environmental contamination. Logically, in the presence of such signals, the collection of available data falls under the purview of the DDASS, which have a more natural connection with other departmental administrations and local authorities. Depending on the context, the DDASS may request assistance from the CIREs or the InVS for the synthesis and analysis of the collected data. (introduction)