Biohazard Symbol
Symbol warning of biological substances that pose a threat to living organisms.
International · 1966 – present
Skull and Crossbones
Universal symbol for poison, toxic substances, and mortal danger.
Description
The skull and crossbones symbol (☠) is one of the most universally recognized warning symbols, indicating poison, toxic substances, or mortal danger. Historically used on pirate flags (the Jolly Roger) and poison bottles, it was incorporated into the GHS (Globally Harmonized System) as pictogram GHS06 for acute toxicity. Under GHS, the symbol appears as a black skull and crossbones on a white diamond with a red border, indicating substances that are acutely toxic by oral, dermal, or inhalation routes.
Origin & Cultural Context
The skull and crossbones as a danger symbol dates to at least the 15th century in European iconography. Its use on poison labels became widespread in the 19th century.