RSPCA welcomes proposed ban on slaughtering pigs with CO2 gas

The RSPCA has welcomed an expert report submitted to the governments across the UK recommending a ban on the use of high-concentration carbon dioxide (CO2) to slaughter pigs – a “painful and distressing” method that is used to stun and kill 90% of pigs in the UK.

Following strong representations from the RSPCA, the report from the Animal Welfare Committee (AWC) – a panel of independent experts that report to the UK, Welsh, Scottish & Northern Irish governments – concluded that the CO2 method caused “avoidable pain, distress or suffering”.

The report recommends that the industry transitions to an alternative stunning method as fast as possible – and certainly within a maximum of five years.

RSPCA Head of Public Affairs David Bowles said: “The committee’s recommendation for a CO2 ban is very encouraging, potentially moving the industry a step nearer to a much more humane way of slaughtering pigs.

“Every year, millions of pigs suffer distress and pain when killed using CO2. Our campaign calling on the UK Government to rapidly end the use of this gas is supported widely by the public.

“Governments across the UK need to show they are committed to building a fairer, kinder food system which puts animal welfare at its heart.

“We urge Ministers to follow through on these recommendations and look forward to contributing to plans for the transition away from high-concentration carbon dioxide (CO2) in pig slaughter, as swiftly as possible.”

The charity launched its campaign in March 2025 with 22,443 people signing a petition urging the UK Government to act.

Every year, millions of pigs suffer distress and pain when killed using carbon dioxide (CO2) in the UK. But it currently remains the most commercially viable method at scale for slaughter/killing pigs. The RSPCA has raised major concerns about the use of high concentrations of CO2 for many years.

The number of pigs experiencing distress and pain when killed using CO2 has been growing – with 90% of all UK pigs now killed in this way, up from 88% in 2022 and 86% in 2018. This also marks a huge increase from a Food Standards Agency survey conducted in 2013, which then found that 51% of pigs were killed with high concentrations of CO2.

Carbon dioxide is an aversive gas used to stun and kill pigs. Research has consistently shown that exposure to this can cause pain, fear and distress in pigs with them seen gasping for air and convulsing before they become unconscious.

Phoebe Hartnett, pig welfare expert at the RSPCA, added: “The stark reality of the impacts this gas has is why mandating a more humane alternative is so urgent. But currently, there is no commercially viable alternative available in the UK, which is why the RSPCA has been calling on the UK Government to fund commercial trials into humane alternatives, such as Argon gas and improved electrical stunning.

“Commercial trials, industry-wide commitment and Government support to help slaughterhouses transition to a new method, all need to happen urgently.

“We cannot ignore the origins of our food or we have no hope of progressing farmed animal welfare. This affects every single one of us who chooses to consume pork products. We have to have these difficult conversations in order to move the UK’s welfare standards forward and improve the lives of these sentient and intelligent animals who deserve a good quality life and a humane death.”