Toxicity of potassium cyanide added to fresh fruit and juice

To investigate the toxicity of potassium cyanide in fresh fruit and juice, male and female Wistar rats were orally dosed with fruit homogenates or juices containing 3 x LD50 of potassium cyanide. These were given in single doses at various intervals after spiking. The dosing solutions were analysed for cyanide using a cyanide test kit. There was a good correlation between the toxic signs in rats and the cyanide remaining in dosing solutions. The toxicity of spiked apple and honeydew melon diminished with time, while spiked grape and both grape and apple juices maintained their toxicity during the 4-hr studies. The pH of the samples both before and after spiking seemed to be an important factor in determining the toxicity.