Microorganisms (food poisoning)}Fluids and gases (organic), e.g., agricultural chemicals, petrol, paraffin, carbon monoxide}Metal poisoning (inorganic), e.g., lead, mercury, copper}Alcohol, drugs of abuse, medicines (in excessive amounts)}Acute poisoning can occur by ingestion, inhalation, injection or cutaneous/mucosal absorption. Exposure can be intentional (e.g., suicide or homicide attempt), unintentional (e.g., medication error) or environmental/ occupational.