Hydractinia echinata test-system. IV. Toxic synergism of human pharmaceuticals in mixtures with iodoform

•Total toxicity of a sample or mixtures depends on nature, concentration and number of components.•Total toxicity is decisively driven by the nature of the highest concentration component.•For close values, the isotoxicity is manifested, in accordance with the Köln model.•Mixtures with Iodoform exhibit reduced overall toxicity/secondary effects.•Mixtures with Iodoform induce pharmacologic-therapeutic effects in shorter time.

The structure-toxicity relationships for a series of singular human stomatological pharmaceuticals preparations and in mixture with Iodoform on Hydractinia echinata were obtained and their synergism was analyzed through the Metamorphosis Reduction Concentration (MRC50) within the “Köln model”. The differences manifested between the total and individual components of the samples and mixtures, associated with toxic versus non-toxic synergism, are dependent on three essential factors of synthesis (the nature, the concentration and the number) besides manifested isotoxicity of the given components. The method represents a practical alternative useful for the reduction of experimental tests on animal to the lowest possible level, in accordance to the ‘3Rs’ (reduce, reuse and recycle) integrative concept.