We have covered the widespread natural occurrence of cyanide in plants, soil and animals here. As we have shown, far from being merely an artificial industrial chemical used mostly in the nylon industry and to colour your jeans (only about 15% of industrial usage is in gold mines) and typical of anthropogenic incursion on this otherwise fair earth, it is a widely dispersed natural compound with a defined cycle in the environment. It is produced AND consumed by plants and fungi. Despite being toxic to most mammals and aquatic life, some creatures develop great tolerance. We keep coming across new and bizarre examples. Case in point it wasn't until 1968 that it became known that the Golden bamboo lemur of Madagascar is able to consume about 12 times the lethal dose of cyanide for most other animals of its size as it prefers to chomp on cyanide laden golden bamboo shoots. The shoots naturally contain 0.015% (1 part in 6667) of cyanide. This is about the concentration used in the gold mining industry to extract gold from crushed and ground rock.
Make you think next time you have noodles and bamboo shoots, right? Kapow!