The topic discusses the confusion surrounding the smell of hydrogen cyanide (HCN) and its relationship with benzaldehyde, which is often mistaken for it. Recent experiments, such as those by chemistry YouTuber NileRed, highlight that HCN does not smell like almonds, contrary to historical claims, but rather has a scent resembling weak bleach or chlorine. Additionally, there are comments regarding the presence of cyanide in stonefruit pits, specifically mentioning that while they contain cyanide, consuming a small amount is unlikely to be harmful due to the need for a large quantity to induce poisoning. Cigarettes are also noted as containing cyanide, suggesting a broader discussion around the presence of cyanide in common substances.