Developmental Toxicology—Teratogenesis

Alterations to the development of the embryo, fetus, or neonatal animal, either morphological or functional, and caused by chemicals is termed developmental toxicology. The result may involve interference with normal growth, homeostasis, development, differentiation, and/or behavior. 

Teratology/teratogenesis is that aspect concerned with the production of malformations. 

Teratogenesis involves interference with the normal development of either the embryo or fetus in utero, giving rise to abnormalities in the neonate. This interference may take many forms, and there is therefore no general mechanism underlying this type of response. Many of the toxic effects described elsewhere in this book may be teratogenic in the appropriate circumstances. 

Teratogenic agents may be drugs taken during pregnancy radiation, both ionizing and nonionizing environmental pollutants chemical hazards in the workplace dietary deficiencies and natural contaminants. 

Embryogenesis is a very complex process involving cell proliferation, differentiation, migration, and organogenesis. This sequence of events (Fig. 6.21) is controlled by information transcribed and translated from DNA and RNA, respectively, (Fig. 6.38) in a time-dependent manner. 

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