A gas chamber is an apparatus for killing humans or other animals with gas, consisting of a sealed chamber into which a poisonous or asphyxiant gas is introduced. Poisonous agents used include hydrogen cyanide and carbon monoxide.
Gas chamber at Majdanek concentration camp
Interior of Majdanek gas chamber, showing Prussian blue residue
The former gas chamber at New Mexico State Penitentiary, used only once in 1960 and later replaced by lethal injection.
A poison is any chemical substance that is harmful or lethal to living organisms. The term is used in a wide range of scientific fields and industries, where it is often specifically defined. It may also be applied colloquially or figuratively, with a broad sense.
Cassava leaves contain cyanide and can thus cause poisoning if not prepared correctly.
Polluted groundwater, in this case depicting acid mine drainage, can cause chronic poisoning.
Poisoning of Queen Bona by Jan Matejko.