Environmental health in emergencies

Deliberate events

Wounded persons and emergency medical team

A deliberate event is an act (or threat) involving the intentional release of hazardous substances to cause harm. Hazardous substances include chemicals, biological agents and radiological materials.

Deliberate events cover a wide spectrum of intent and public health impact. They can be on a small scale, for example, contaminating a few samples of a product to extort money from a retailer. They can also be on a large scale, such as the deliberate release of biological, chemical or radionuclear material for terrorist purposes.

One famous deliberate event happened in 1995 when members of the Aum Shinrikyo sect deliberately released sarin nerve gas into the Tokyo subway.

In many countries, a common form of deliberate use of chemicals is the addition of methanol to counterfeit or illicit alcoholic drinks. In 2005, for example, at least 21 people died in Turkey after drinking a counterfeit brand of raki. In 2006, in Nicaragua, 788 people were poisoned by methanol and 44 died after drinking contaminated guaron – a brandy-like liquor.

Key resources


Deliberate chemical release: FAQs

Initial clinical management of patients exposed to chemical weapons - Interim guidance document

Basic equipment for decontamination (A3 poster)

Decontamination steps (A3 poster)

Initial management flowchart (A3 poster)

Signs and symptoms of exposure (A2 poster)

Related sites