In 1999, the Dioxin Affair occurred when 50 kg of PCB transformer oils were added to a stock of recycled fat used for the production of 500 tonnes of animal feed, eventually affecting around 2,500 farms in several countries. The name Dioxin Affair was coined from early misdiagnosis of dioxins as the primary contaminants, when in fact they turned out to be a relatively small part of the contamination caused by thermal reactions of PCBs. The PCB congener pattern suggested the contamination was from a mixture of Aroclor 1260 and 1254. Over 9 million chickens, and 60,000 pigs were destroyed because of the contamination. The extent of human health effects has been debated, in part because of the use of differing risk assessment methods. One group predicted increased cancer rates, and increased rates of neurological problems in those exposed as neonates. A second study suggested carcinogenic effects were unlikely and that the primary risk would be associated with developmental effects due to exposure in pregnancy and neonates. Two businessmen who knowingly sold the contaminated feed ingredient received two-year suspended sentences for their role in the crisis.