This document discusses chemical hazards in antibiotics, specifically: 1. It categorizes chemical hazards into naturally occurring, intentionally added, and unintentionally added chemicals. Antibiotics can contain unintentionally added chemicals from raw materials or packaging. 2. It describes various mechanisms of action of antibacterial drugs including inhibition of cell wall synthesis, protein synthesis, nucleic acid synthesis, and metabolic pathways. 3. It discusses EU legislation around antibiotic residues in food including definitions of maximum residue limits and prohibited substances. Monitoring programs help enforce regulations and issue alerts when risks are detected.