LARGE livestock farms in Scotland are fuelling a rise in deadly ammonia emissions, the Sunday National can reveal.
The 975 tonnes of ammonia emitted to the air last year was the highest amount since 2011 according to figures from the Scottish Environment Protection Agency’s (Sepa) annual inventory of industrial pollution.
The 2023 figure represents a 21% increase since 2016. However, the total figure is actually likely substantially higher.
Agriculture – particularly intensive livestock farms – is responsible for around 90% of ammonia emissions, largely due to the use of ammonia as a fertiliser and from animal waste.
But Scottish dairy and beef farms – unlike pig and poultry farms – do not need to report emissions to Sepa and therefore aren't included in the data.
Also, only intensive farms are legally required to report estimated ammonia emissions to Sepa under the Pollution Prevention and Control (Scotland) Act – sites that have a capacity of more than 40,000 poultry, 2000 pigs or 700 sows.
Ammonia pollution is particularly dangerous when released into the atmosphere and when it combines with other pollutants to create PM2.5, one of the world’s most deadly air pollutants.
Exposure is particularly bad for your heart and lungs – leading to heart attacks, strokes, chronic obstructive pulmonary diseases, asthma and even lung cancer.
It’s estimated that ammonia pollution leads to thousands of excess deaths in the UK every year – a large proportion of which could be avoided if ammonia emissions from farms were halved.
But Sepa data shows that the twenty largest ammonia polluters (19 of which are farms) in Scotland are fuelling the rise in emissions in recent years – from 431 tonnes in 2020 to 504 in 2023, an almost 15% increase in that timespan.
The 10 largest ammonia polluters across Scotland in 2023 according to Sepa data are marked on the interactive map below:
Pete Ritchie, executive director of food policy charity Nourish Scotland, said ammonia is a "serious air pollutant" which harms both biodiversity and human health.
"While other air pollution has reduced in recent years, ammonia has not," he added.
"We need farmers running these large intensive farming systems to use best available techniques to reduce ammonia emissions to air, and capture what they can with shelter belts before it leaves the farm. "
Reducing ammonia pollution in agriculture is a key part of the Scottish Government’s Cleaner Air For Scotland strategy, which has also noted that, while there has been an encouraging downward trend in air pollution levels in Scotland, ammonia pollution has remained relatively static for decades.
Animal welfare campaign group Compassion in World Farming (CWF) said that there should be an immediate moratorium on granting permits for mega farms.
An investigation by CWF in February found a huge rise in so-called US-style mega farms in the UK – including the number of megafarms for pigs doubling in Scotland since 2017, while massive poultry units have increased by a fifth.
This is deeply concerning, for not only is intensive farming bad for farmed animals and river pollution but increasing air pollution including ammonia levels, causes toxic damage to nature and leads to respiratory problems for people," Anthony Field, the organisation's head of UK told the Sunday National.
"Despite this, all UK local councils, including Scottish planning authorities, are still giving the green light to new or expanding factory farm applications, when instead there should be an immediate moratorium on granting permits for these farms.
"We need better joined-up thinking in government and start to mend our broken farming system.”
As well as the risk to human health, there are concerns over the risk of increasing environmental damage due to ammonia-linked nitrogen accumulation.
It comes as ammonia pollution in water in Scotland remains stubbornly high.
In 2023, almost 11 thousand tonnes of ammonia was released into the water – the second highest figure (after 2022) since SEPA records began in 2015.
In fact, ammonia pollution to water has almost doubled in Scotland since 2016.
Scottish Greens MSP Mark Ruskell (above) told the Sunday National that the figures were very worrying.
“The health effects are well known, [such as] the way that ammonium combines with other pollutants and causes particulate pollution.
“But we're not seeing enough action from the Scottish Government, in terms of regulation to drive investment in the farming sector, to tackle this problem.”
He added that this was certainly a “blind spot”, particularly in relation to the Government’s Clean Air Strategy.
“If you look at the Netherlands, for example – [there are] a lot of dairy farms there – they are investing in anaerobic digestion.
“So, instead of allowing the methane to escape to the atmosphere or into the soil, into the water, they're capturing and using it to create biogas and generate electricity.
“Efficient farms should be seeing methane as a resource, ammonia as a resource.
“But it will require investment that will require farms going beyond just collecting slurry and applying that to fields.”
He added: “At the moment, this is just going up into the atmosphere, taking nitrogen away from the farms where it's causing human health problems. When it gets into water courses, it ends up causing a water pollution problem as well.
“So all these things are linked together.”
A spokesperson from Sepa said: “Sepa directly regulate emissions from intensive pig and poultry units in Scotland via controls in Pollution Prevention and Control (PPC) permits.
"We provide clear guidance for farmers on best available techniques for preventing or, where that is not practicable, reducing emissions from livestock housing and manure management and storage within the permitted installation. We carry out inspections at intensive pig and poultry farms to assess compliance.
“The PPC permit conditions do not cover the scope of applying the slurry from licenced pig units to land, however, under general binding rule 18, slurry produced from these units must be applied using low emission/precision technology.
"We also encourage operators to consider covered storage of poultry litter. Maximising the value out of the nutrients in livestock manures and slurries by effective controls at source can also be a win-win for land managers and the environment.
“Sepa welcomes action to reduce ammonia and nitrogen emissions to air, including the development of a voluntary code of good agricultural practice for improving air quality and other measures as outlined in Cleaner Air For Scotland 2 – A Better Place For Everyone, which we will contribute to developing with our partners.”
NFU Scotland has been approached for a comment.
