BLUE GODS, BLUE OIL, AND BLUE PEOPLE

Studies of the composition of coal tar, which began in Prussia in 1834 , profoundly affected the economies of Germany, Great Britain, India, and the rest of the world, as well as medicine and surgery. Such effec ts include the collapse of the profits of the British indigo monopoly, the growth in economic power of Germany based on coal tar chemistry, and an economic crisis in India that led to more humane tax laws and, ultimately, the independence of India and the end of the British Empir e. Additional consequences were the development of antiseptic surgery and the synthesis of a wide variety of useful drugs that have eradicat ed infections and alleviated pain. Many of these drugs, particularly t he commonly used analgesics, sulfonamides, sulfones, and local anesthe tics, are derivatives of aniline, originally called ''blue oil'' or '' kyanol.'' Some of these aniline derivatives, however, have also caused aplastic anemia, agranulocytosis, and methemoglobinemia (that is, ''b lue people''). Exposure to aniline drugs, particularly when two or thr ee aniline drugs are taken concurrently, seems to be the commonest cau se of methemoglobinemia today.