Investigation reveals no plan is in place to tackle increase in levels of agricultural ammonia, a gas contributing to thousands of deaths in UK alone

One of the most potent air pollutants is on the rise in the UK, but the government has no comprehensive monitoring, little enforcement, and almost no funding or clear plan to reduce the emissions, an investigation has found.

Evidence obtained by a joint investigation by the Guardian, the Bureau of Investigative Journalism and Channel 4 News suggests that at least 3,000 deaths each year could be avoided if agricultural ammonia emissions were halved.

The hidden danger of ammonia – the pungent, irritant gas that comes from livestock farms and combines with other chemicals in the air to form deadly particulates – has been largely ignored by the government, despite pledges from ministers to slash air pollution. Ammonia is the only major air pollutant rising in the UK, as other forms of pollution have dropped.

The findings of the investigation include:

Government inaction and regulatory failings mean the most polluting farming sectors – dairy and beef cattle – are under no obligation to monitor, report or reduce ammonia emissions.

Despite promising to close this loophole by 2025, Michael Gove, the environment secretary, has not laid out a clear plan or any legislation to do so. In the meantime, the number of intensive US-style beef feedlots and dairy “megafarms” has been increasing.

Leaked documents show that cuts in staffing at the Environment Agency, which polices farm pollution, mean a lack of resources to carry out even basic monitoring.

Demand for cheap food adds to the problem, as many farmers operate on thin margins. Brexit is likely to exacerbate this, as current EU subsidies will disappear, and farmers may face crippling export tariffs under a no-deal scenario. In addition, the UK may be flooded with cheap imports from countries with lower welfare standards as part of new trade deals.

The vast majority of ammonia emissions in the UK come from livestock manure. When it mixes with other forms of pollution from vehicles or industry, it forms airborne particles called PM2.5, which are linked to respiratory problems, cardiovascular diseases, cognitive decline and low birth weights.

“PM2.5 is probably responsible for somewhere between half and three-quarters of the total harm we derive as humans from air pollution,” said Alastair Lewis, director for composition research at the National Centre for Atmospheric Science. About half of PM2.5 in urban areas comes from ammonia.

In high concentrations, such as found near liquid manure stores, ammonia can cause a stinging sensation in the eyes and throat and an overpowering acrid smell; if inhaled for too long, it can cause eye damage or even death. In lower concentrations, it causes irritation.

Andrea Pozzer, head of a research group at the renowned Max Planck Institute for Chemistry in Germany, has studied the impact of ammonia, finding that 50,000 deaths from air pollution could be avoided annually in Europe if agricultural emissions were halved. In the UK, this equates to at least 3,000 deaths a year.

“Ammonia is playing a lead role in fine particle formation and the reduction of it could really improve air quality,” said Pozzer.

Earlier this year, the Department for Environment, Food and Rural Affairs (Defra) released its first attempt to get to grips with the ammonia problem. But the strategy contained no timetable for ammonia reductions, no measurements and no plans to help farmers adopt the kind of technology and methods that would swiftly and drastically reduce today’s emissions.

From the 1990s until 2013, ammonia emissions fell by about a fifth in the UK as livestock production in some areas declined, and fertiliser use changed. But in the past six years they increased by more than a tenth, even as other air pollutants fell.

A Defra spokesperson said: “Our clean air strategy sets out for the first time how we plan to tackle farm ammonia pollution by requiring and supporting farmers to invest in the infrastructure and equipment required to reduce emissions. We have already published guidance on how farmers can take action and will consult later this year on policy to reduce emissions from urea fertilisers, the first in a series of rules to reduce ammonia emissions from farming.”

For most farms, reducing ammonia does not require hi-tech solutions. Covering slurry pits, where manure is held before being used as a fertiliser or disposed of, can prevent emissions, as can injecting slurry into the soil for fertilisation instead of spreading it through the air. “Many of these methods offer cost savings for farmers, reducing the need for bought-in fertilisers,” said Mark Sutton, environmental physicist at the Centre for Ecology and Hydrology. “Where capital grants are available, these can help farmers with the up-front costs of equipment, but ultimately the goal is that low-emission methods end up paying for themselves.”

Facebook Twitter Pinterest A farmer spreads manure over a field in the Scottish Borders. Photograph: Chris Strickland/Alamy

But for a comprehensive ammonia reduction strategy, more information is needed on the sources of the gas. Currently, the government only collects data from a small number of intensive facilities that house more than 40,000 birds, 2,000 pigs or 750 sows.

An analysis of government data as part of the investigation found emissions from these facilities in England and Scotland rose by 2.6% from 2015 to 2017.

The much larger unregulated sector, for which no data is available, produces many times more ammonia, however. Cattle farms account for about 44% of the UK’s total ammonia emissions, but require no environmental permits and are unmonitored for ammonia, while many more livestock units keep animal numbers just below the threshold for regulation.. Defra has pledged to extend environmental permitting to intensive “mega farm” cattle units by 2025, but details are lacking.

A further problem is that swingeing cuts at the Environment Agency mean there are not enough staff to enforce regulations. A leaked email shows at least one official admitting that staff cutbacks are endangering the agency’s ability to monitor the problem. Without such monitoring, farmers can – knowingly or unknowingly – breach what regulations there are, for instance by gaining planning permission for one type of building then converting it to livestock sheds without the appropriate planning permission, or the right kind of slurry storage.

The Environment Agency said that it had 10% more operations staff than in 2009, including those who visit farms and rivers, and that it has 6,500 officers across England trained and ready to respond to environmental incidents on farms. It said the agency was the largest of its kind in Europe, with an annual budget of more than £1bn.