Pyrogallol: A trihydroxybenzene or dihydroxy phenol that can be prepared by heating GALLIC ACID.BenzocycloheptenesToxicity Tests, Chronic: Experiments designed to determine the potential toxic effects of a long-term exposure to a chemical or chemicals.Gallic Acid: A colorless or slightly yellow crystalline compound obtained from nutgalls. It is used in photography, pharmaceuticals, and as an analytical reagent.Hydroxocobalamin: Injectable form of VITAMIN B 12 that has been used therapeutically to treat VITAMIN B 12 DEFICIENCY.HydroquinonesPhloroglucinol: A trinitrobenzene derivative with antispasmodic properties that is used primarily as a laboratory reagent.Micronuclei, Chromosome-Defective: Defective nuclei produced during the TELOPHASE of MITOSIS or MEIOSIS by lagging CHROMOSOMES or chromosome fragments derived from spontaneous or experimentally induced chromosomal structural changes.Tannins: Polyphenolic compounds with molecular weights of around 500-3000 daltons and containing enough hydroxyl groups (1-2 per 100 MW) for effective cross linking of other compounds (ASTRINGENTS). The two main types are HYDROLYZABLE TANNINS and CONDENSED TANNINS. Historically, the term has applied to many compounds and plant extracts able to render skin COLLAGEN impervious to degradation. The word tannin derives from the Celtic word for OAK TREE which was used for leather processing.Ditiocarb: A chelating agent that has been used to mobilize toxic metals from the tissues of humans and experimental animals. It is the main metabolite of DISULFIRAM.