Toxic Response

This chapter provides an overview of the classification of toxic reactions of various substances according to their physiological background (direct cell or tissue damage, neurotoxicity, immunotoxicity, genotoxicity and mutagenicity, group of reproductive toxicities) and according to the more detailed molecular mechanisms of their toxic effect, such as receptor-mediated mechanisms, disruption of cell energetics, covalent binding to essential cellular macromolecules that is a basis for cancer development. Special attention is paid to the latter mechanism since carcinogenicity is one of the most important outcomes of toxicity and the balance of oxidants-antioxidants (oxidative stress) as a well-distributed mechanism of toxic effect which, according to current knowledge, plays an important role in a majority of complex mechanisms.