Hydrogen cyanide

Hydrogen cyanide, also known as prussic acid, is a toxic liquid that is said to smell like bitter almonds. It is found in fruits that have a pit, such as cherries and bitter almonds. Its toxicity is due to it binding hemoglobin. Treatments include vitamin B12 hydroxide, which captures the HCN, stopping it from binding to hemoglobin. The cyano-B12 then leaves the body.