international pictogram for chemicals that are sensitising,<unk> ic, carcinogenic or toxic to reproduction. In genetics, a<unk>  is a physical or chemical agent that permanently changes genetic material, usually DNA, in an organism and thus increases the frequency of mutations above the natural background level. As many mutations can cause cancer, such<unk> s are therefore carcinogens, although not all necessarily are. All<unk> s have characteristic mutational signatures with some chemicals becoming<unk> ic through cellular processes. The process of DNA becoming modified is called<unk> esis. Not all mutations are caused by<unk> s: so-called "spontaneous mutations" occur due to spontaneous hydrolysis, errors in DNA replication, repair and recombination.
Mutagen
Antimetabolite
Specifier 
Toxicophore
Mitogen
Saponification
Pollutant
Azo compound