Modelling acute oral mammalian toxicity. 1. Definition of a quantifiable baseline effect

► Acute oral toxicity data (LD50) were used to derive rat and mouse baseline toxicity models. ► The non-linear QSARs were fitted by saturated monohydric alcohols and monoketones. ► Predictivities of the models were evaluated with an external hydrocarbon test set. ► The models allow for the formation of mechanistic categories for excess toxic chemicals. ► Species sensitivity was assessed by the relationship between LD50 values for rat and mouse.