A teratogen is any agent—chemicals, viruses, environmental agents, physical factors, and drugs—that acts during embryonic or fetal development to produce a permanent alteration of form or function. The word teratogen is derived from the Greek teratos, meaning monster. A hadegen—after Hades, the god who possessed a helmet conferring invisibility—is an agent that interferes with normal maturation and function of an organ. A trophogen is an agent that alters growth. Hadegens and trophogens generally affect processes occurring after organogenesis or even after birth. Chemical or physical exposures that act as hadegens or trophogens are much harder to document. For simplification, most authors use the word teratogen to refer to all three types of agents.
Last summer one terror state, Israel, massacres 1400 Palestinian civilians in Gaza, then this summer another terror state, ISIS, threatens to do in Gaza what it did in Yarmouk. But let’s all cry about summer vacation in Israel?