Exploring community-based environmental hazard assessment of mixtures using mode-of-action based approaches

INTRODUCTION The assessment of the risk of chemicals to the environment is generally concerned with the assessment of single chemicals or products. [...] Assuming exposure, the potential for effects is driven by the mode-of-action (MoA) of the chemical, that is the interaction between the chemical and the organisms at a cellular and sub-cellular level. [...] The fate of the chemicals is determined by the characteristics of the receiving water bodies, as well as the physical and chemical properties of the compounds themselves. [...] (2006) looked at the spray program for potatoes in the Netherlands where there was a single application of the herbicide prosulfocarb, followed by a single application of another herbicide metribuzin, then two applications of the insecticide lambda-cyhalothrin and four and eight applications, respectively, of the fungicides chlorothalonil and fluazinam. [...] In contrast to this, Toxicodynamic (TD) models describe the time course of toxic action at the target site, physiological impairment of the organism as a result of the exposure as well as the influence of any compensating mechanisms and toxic effects of the chemical on the organism (i.e.