Other subjects explored include hydrogen bonding effects on the photochemistry of chromophores in solution, photochemical generation of silicon-centered radicals and their reactions, and photochemical processes at the air-water interface of atmospheric droplets.
Caffeine is a central nervous system (CNS) stimulant of the methylxanthine class of psychoactive drugs. It is the world's most widely consumed psychoactive drug, but unlike many other psychoactive substances, it is legal and unregulated in nearly all parts of the world.
The Food and Drug Administration (FDA) includes Caffiene on the list of substances Generally Recognized as Safe (GRAS) as a multipurpose food substance. Caffiene is considered GRAS when used in cola-type beverages. Caffeine is also approved for use as an active ingredient in Over-the-Counter (OTC) stimulant drug products. The Cosmetic Ingredient Review (CIR) Expert Panel has deferred evaluation of this ingredient because the safety has been assessed by FDA.