Intensive Pig CO2 Stunning Reform

Carbon dioxide stunning of pigs is widely used before slaughter but causes significant suffering. Alternatives are being developed and implemented.

Key Facts

CO2 stunning causes aversion, breathlessness, and distress before unconsciousness
Pigs attempt to escape CO2 environments and vocalise intensely in the first phase of exposure
The aversive phase typically lasts 20-30 seconds before unconsciousness occurs
Controlled atmosphere stunning with inert gases such as argon or nitrogen is more humane
High concentration CO2 above 80% may reduce aversion time but remains aversive
Some countries and companies have begun transitioning to inert gas systems
Electrical stunning is an alternative that can be effective but carries welfare risks if parameters are inadequate

Welfare Considerations

CO2 stunning is one of the most significant unresolved welfare problems in pig slaughter. Scientific consensus is clear that CO2 causes significant suffering before unconsciousness. The technology for more humane alternatives exists but requires capital investment. Major pork purchasers have the leverage to drive transition through procurement requirements, and several are beginning to apply this pressure.

What You Can Do

Ask pork suppliers about their stunning method and whether they plan to transition from CO2
Support retailers and food companies committing to transition away from CO2 pig stunning
Choose pork from facilities using controlled atmosphere with inert gases where available
Support industry standards and regulatory requirements for CO2 stunning phase-out