IEHIAS models: example from agriculture

The text on this page is taken from an equivalent page of the IEHIAS-project.

As part of the EU-funded INTARESE project, which contributed to the development of this Toolbox, a case study was done to assess the health impacts of agricultural land use change in Greece and England.

This assessment comprised a prognostic analysis of the potential health effects of changes in agricultural land use. The first step involved scoping the problem in a clear and concise way. This was done through a series of consultations between the scientists involved, and with representatives from several stakeholder groups and data providers.

Initial scoping was done using mind-mapping methods. The resulting model was then refined and revised, to provide a more structured view of the problem, in the form of a systems diagram. In the process, reviews were carried out of the relevant scientific studies, to help identify which potential risk factors might be most important in affecting human health. As a consequence, three key risk factors emerged: pesticides, endotoxins and aerosols. Others that were initially considered for inclusion (e.g. health effects of nitrates) were omitted because of lack of sufficient evidence for significant health effects. In the same way, possible health outcomes of interest were defined. These focused mainly on respiratory effects (from all three agents) and cancers (from pesticide exposures).

While the resulting mind-map provided an indication of the scope of the assessment, it was not the end of the story. As part of the process of assessment design, it had to be further revised and more tightly specified to give a firm basis for assessment as reflected in the final causal diagram.