The biochemistry of benzpyrene; a survey, and new methods of analysis.

The fate of benzpyrene after administration to animals was first investigated by Peacock (9, 20, 21). By making use of the characteristic fluorescence spectrum he was able to discover the main facts: that it is removed from the blood stream in unaltered form by the adipose tissue and all tissues and glands containing fat solvents, and especially that it is metabolized to new derivatives having different fluorescence spectra. These researches were continued in Glasgow by Pea. cock in co-operation with Beck, Chalmers, and Kirby; at Oxford by Berenblum, Crowfoot, Holiday, and Schoental; and at the Mount Vernon Hospital in Northwood by Doniach, Mottram, and Weigert. The following is a list of the facts so far established: 1. The course of events is always essentially the same and independent of the mode of administration, whether by intravenous, subcutaneous, intraperitoneal, or intramuscular inoculation; by feeding, or by painting the skin (11, 12, 20, 21). 2. Goats, rats, mice, and fowls show essentially the same mechanism of elimination (20), whereas in rabbits there are indications of a different metabolism (4). 3. Unchanged hydrocarbon disappears completely from the site of application after varying periods of time, and very little appears in the unchanged form in the feces, urine, or other secretions (3, 5, 6, 8-10); only after feeding (12) do considerable amounts of unchanged hydrocarbon appear in the feces.