Air pollution from intensive pig and poultry farms costs England and Wales over £131 million a year, contributing to cases of asthma, stroke, and heart disease, it can be revealed.

A new analysis by DeSmog and the Bureau of Investigative Journalism estimates that ammonia pollution from England and Wales’ largest 1,200 farms causes an average of at least 25 hospital admissions and over 1,000 lost years of life due to premature death each year.

Agriculture is a major cause of air pollution, which damages children’s neurological development, and contributes to 4.9 million premature deaths worldwide every year. Farming is responsible for around 90 percent of all ammonia emissions in the UK – a pollutant that can react to form PM2.5, tiny particles so small they can enter the lungs and blood stream.

Residents living close to the intensive farms described plumes of foul-smelling pollution blowing into villages, which they said made breathing difficult and had exacerbated their asthma. 

Invisible ammonia pollution can also travel hundreds of miles: a study in 2023 suggested that farming could be responsible for between a quarter and a third of PM2.5 in UK cities.

The new £131 million estimate includes the cost of NHS care and lost economic productivity, as well as early deaths linked to air pollution from the farms. The economic cost from these farms was found to be higher than the health costs from 3.5 million petrol cars.

The analysis combined mandatory reporting by intensive farms — each housing over 40,000 chickens, 750 sows, or 2,000 pigs for meat production — with government estimates for ‘damage costs’ and health impacts per tonne of pollutant. 

The investigation found, however, that government rules had left some of the biggest polluters exempt. All intensive pig and poultry farms must submit air pollution estimates to the government under their environmental permits. But regulators do not currently require cattle farms to have environmental permits or to report air pollution data, despite being responsible for around half of ammonia in the UK.

Air pollution is produced on livestock farms from animals’ faeces and urine, which emit large amounts of nitrogen, a chemical that reacts to form ammonia. However,  farms do not have to report air pollution from manure once it is spread on local fields or incinerated — emissions that can be several times as large as those produced on the intensive livestock farms themselves. 

The UK has made major strides tackling sources of other pollutants. However, while ammonia emissions from agriculture fell by nearly 20 percent since 1990, they have increased since 2008, driven by rises in pollution from cattle farming.

Dr Helen Wood, a research fellow at Queen Mary University of London told DeSmog that PM2.5 derived from ammonia pollution can damage cells, tissues, and organs throughout the body. 

“Air pollution like this comes at a very high cost to the healthcare system: these are chronic conditions, that need managing overtime. People often get chronically sicker. They may not be able to work, they may need care. Their healthy life expectancy is reduced. This all comes at a price.”

A spokesperson for the Department for Environment, Food and Rural Affairs (Defra) told DeSmog: “We are committed to improving air quality, whilst supporting a productive, modern and sustainable farming sector. As part of this, we are helping farms invest in sustainable infrastructure that improves the use of organic nutrients, supports productivity, and reduces pollution.”

“This evidence is clear; industrial animal production is a risk to our health,” said Ruth Westcott, campaign director at the advocacy group Foodrise. “To prevent more people getting sick, we need to regulate this industry much better.” 

‘Breathless’

Residents living close to megafarms have repeatedly raised alarm bells about the impacts of air pollution on their health.

Roy lives less than a mile from an intensive pig farm in Norfolk, where he worked for nine years, and says that his health conditions have been exacerbated by pollution and airborne bacteria from the farm. 

“I was always going back and forth with my doctor because I couldn’t get my breath,” he told DeSmog. “My doctor told me: ‘it’s part and parcel with where you’re working. It’s everything you’re breathing in.’ It was very scary – all my life I’d never been in hospital [before].”

So far, few studies have looked at the impact of intensive farm pollution on communities in the UK. However,  research in the Netherlands, the US and other regions have found links between living close to livestock farms, asthma symptoms, reduced lung function, and lung damage, although with some mixed results. 

Roy is 75 and is now retired, but he says the pollution blows over his house and the neighbouring village, bringing a foul smell with it most weeks. “I’m very breathless when the odours come across. That’s when I go into the house and don’t come out. 

“I feel it all the time. I take an inhaler every day, and I have one I carry with me for an emergency if I can’t get my breath.”

Alasdair, a retired navy officer who lives opposite an intensive poultry farm in Suffolk, also says he can smell the ammonia pollution. “The wind blows away from me, but it still stinks.”

“I’m 87 now, maybe it’s natural, but I’ve had lots of coughing and wheezing. A couple of years ago I had bronchitis. If I go out at night, with a torch, I can see the dust and feathers flying about. It’s like shining a torch into snow. I know I’m breathing that stuff in.” 

Alasdair and Roy both live in hotspots for ammonia pollution: the new analysis found that East Anglia, including Norfolk and Suffolk, had the highest ammonia emissions from intensive pig and poultry farms, with over 220 farms emitting a combined total of nearly 2.5 million kg every year. Yorkshire, Lincolnshire and Northamptonshire, and the West Midlands had the next highest emissions. 

The regions are already home to some of the worst asthma rates in the UK: one in nine residents in East Anglia’s coastal village Mundesley have the condition, the highest figure in the whole of the country.

City Pollution

Experts say that farming pollution is also having a significant and under-recognised impact on cities. A 2023 study found that it contributed to 38 percent of the particle pollution in Leicester, 32 percent in Birmingham, and 25 percent in London. 

“Ammonia emissions from farming drift long distances in the air, sometimes many hundreds of kilometres, and can impact huge numbers of people,” Alastair Lewis, professor of atmospheric chemistry at the University of York, told DeSmog. “When they later mix with air that has been polluted for example by vehicles or power stations, then particulate pollution forms. 

“It isn’t intuitive, but those living in city centres are subjected to substantial amounts of PM2.5 [health-harming particulates]  in part caused by agriculture,” he said.

In 2019, an investigation by the Bureau of Investigative Journalism found that halving air ammonia pollution from farms could avoid 3,000 deaths each year. 

Jemima Hartshorn, founder and director of campaign group Mums for Lungs, called for greater action on agricultural pollution in light of the findings. 

“The stuff that is coming out of the pig farm or off the field today will be breathed in in London, Birmingham and Manchester tomorrow,” she said, noting that in London alone over 100,000 children are hospitalised each year due to severe breathing problems. 

“Our children should be at home having dinner, playing tag with their mates, learning to read and skateboard, but instead they are in hospital,” she said. “The cost is insane at a time when the NHS cannot cope.”

In 2025, a report commissioned by the UK government recognised that air pollution had high costs for the UK economy due to early mortality and widespread hospital admissions linked to asthma in children, lung cancer, and heart diseaseamong other health impacts. 

Paul Behrens, a professor specialising in food systems at the University of Oxford, says the costs from pollution could in fact be even higher than previously recognised. 

“Every time I look at the [research] literature there are more problems associated with PM2.5. We now know it affects birth outcomes and increases type 2 diabetes, we’ve learned how it can trigger lung cancer in people who have never smoked. There’s growing evidence linking it to dementia and depression,” he said. “The impacts have kept growing and we have repeatedly underestimated the costs.”

Data Gaps

The £131 million total provides just a snapshot of total emissions linked to the farms.

The UK government only requires farms to report on pollution from animals and manure while stored on farm. But large amounts of ammonia are also released by the manure once it is transported off site to be incinerated or spread on fields as fertiliser. 

Analysis by multimedia research agency Materiality and advocacy groups Compassion in World Farming and Sustain found that ammonia pollution from the manure spread on fields could be up to five times as large as on-farm pollution in some circumstances. 

Campaigners are now calling on Defra to strengthen its environmental permitting scheme in light of the findings. 

“Right now you need an environmental permit if you run a dry cleaners or a [large] petrol station, but not for a facility with 39,000 chickens or a mega-dairy with 1,000 cows, even though they produce as much faecal matter as a small town,” Westcott of Sustain said. 

Defra claims that permitting has played a significant role in cutting ammonia from pigs and poultry in recent years. However, reductions have been offset by major increases in emissions from dairy cattle. 

The government announced that it would extend environmental permitting to the dairy and intensive beef sectors in 2019, but is yet to implement the changes. In its Farming Roadmap published in June, it said that it would consult on whether to include cattle farming, and DeSmog understands that a final decision will be reached following the consultation.

“British farmers take their roles in producing food while protecting the environment, their neighbours and public health extremely seriously,” Paul Tompkins, deputy president of the National Farmers Union, told DeSmog. “We recognise the need to continue reducing ammonia emissions from agriculture and farmers are taking steps to do so.”

But Westcott said that without proper regulation, there was little prospect for change. The public was “still waiting” for improvements in the permitting regime, she stated, “and in the meantime, people are getting sick.”