In 1955, Dr Cihad Çam, a dermatologist in Diyarbakir in eastern Turkey, saw a large number of children with sores and blisters on their faces and on the backs of their hands. They had dark pigmented skins and great hairiness on their arms, hands and faces. They were described by their neighbours in the villages as the ‘monkey children’ because of their hairiness. Their urine was a reddish-brown. When Dr Çam examined their urine in ultraviolet light, using a ‘Woods filter’ to block the white light, it showed a brilliant pink fluorescence. He realised then that these children's symptoms had probably been caused by some form of porphyria. Between 1955 and 1960 he had seen many hundreds of affected children and adults.

Dr Çam took the dietary history of the children with porphyria. The peasants in the eastern part of Turkey, many of them Kurds, were, and still are, very poor; bread was their main diet. To obtain good wheat crops in the area, it was necessary to treat the seed-wheat with a fungicide, or else the seed-wheat would be destroyed in the soil by the fungus Tilletia Tritici. Before 1953 the seed-wheat had been treated with mercurous chloride, which had not proved to be very effective and the wheat crops were poor. In 1954, seed-wheat was sent by the United States to eastern Turkey, treated for the first time with the fungicide hexachlorobenzene. This seed was distributed for planting in Urfa Province and, in 1955, was also sold in the neighbouring provinces of Diyarbakir and Mardin. Dr Çam found that the affected children had been eating bread made from the seed-wheat. He quite rightly suspected that this wheat, or what had been added to it, was responsible for the epidemic.