Chemical properties of caustic substances

The degree of injury following a caustic ingestion depends on the chemical properties of the agent, including:

• type of agent
  • household bleach, detergents, ionic surfactants and ammonia cause less severe effects than strong alkalis (eg sodium hydroxide) and strong acids (eg hydrochloric or sulfuric acid)
  • hydrofluoric acid ingestion can cause local caustic injury and systemic effects (see Hydrofluoric acid poisoning for more detail)
• concentration of the agent
• volume or amount ingested
• pH of the agent—pH of more than 12 or less than 3 (eg oven cleaners, commercial dishwasher detergents, acids and drain cleaners) are associated with severe injuries even after ingestion of small quantities
• formulation of the agent
  • solid formulations can stick to mucosal surfaces and are more likely to cause severe injury than liquids
  • button batteries can stick to mucosal surfaces and electrical discharge causes corrosive injury and viscus perforation (eg oesophageal perforation) (see Button battery ingestion for more detail).