The ammonia problem on farms.

The metropolitan area of Barcelona and El Vallès are the hot spots for pollution. A large part of the polluting gases is generated there. In these environments, the majority of polluting agents come from industrial activity and traffic by land, sea, and air.

But each summer with the arrival of heat, another problem is added to the already fragile balance of air quality in the city and its metropolitan area. Or more worrisome than industrial pollution is the pollution generated in the area of the Vic plain, where the high levels of tropospheric ozone reached by livestock activity in these hottest months, even have an impact on the already fragile quality of the air of the Catalan capital and his metropolitan area.

If we put together the levels of ammonia, with all the pollution generated by the port, industrial activity, airport, and traffic, we find ourselves with an explosive cocktail that is expanding more and more.

The Public Health Agency of Barcelona has detected that part of the polluting particles that remain in the city’s air corresponds to ammonia from the pig farms in the Vic plain and the rest of Catalonia.

Much has been said, measured, and warned about the contamination of the aquifers by slurry suffered by the areas of Catalonia where pig farms are concentrated. But the contamination that this mixture of urine with excrement causes in the atmosphere is not so well known, due to the elimination of nitrogen in the form of ammonia, mainly through urine. In six years, air pollution from slurry emissions has doubled (from 9,500 tons in 2012 to 21,000 in 2018, according to the official PRTR pollutant register). An alarming fact, and more when the rest of the emissions are reduced.

The CSIC researcher Xavier Querol, points out that the problem of ammonia emissions from slurry “is European in scope and affects a sector that has evolved very little, while the industry has put its batteries together.”