The urease inhibitor Nitroshield, supplied by fertiliser company Omex has been granted EU approval.

The inclusion of Nitroshield with liquid fertiliser containing nitrogen designed for uptake through the roots, will reduce ammonia emissions, improve nitrogen use efficiency (NUE), and consequently improve yield or provide the option of applying less nitrogen, Omex has said.

According to Omex, trials show ammonia emissions from Omex's Nitroflo range alone are less than a third of that from urea – and similar to emissions from protected urea.

The addition of Nitroshield produces an average emissions reduction of 70% compared with Nitroflo without the inhibitor, Omex technical director David Booty said.

"In lab conditions, less than 4% of applied nitrogen was lost to the atmosphere when Nitroshield was included," he added.


The impact of Nitroshield's approval will be particularly significant for farmers in Ireland according to Omex’s speciality products director, Edward Dickinson.

“Ireland’s twin challenges of nitrate leaching from CAN in the east, and ammonia emissions from urea use in the west, can be significantly reduced by using Nitroflo and Nitroshield together,” he explains.

“The combined benefits of accurate application through a sprayer, no waste outside of the cropped area, no yield loss on field margins from the liquid, and environmental benefits of less leaching and very effective protection against ammonia loss, make this combination a really viable alternative to protected urea.

“Farmers using Nitroflo and NitroShield together will be able to declare their inhibitor use under the new DAFM regulations introduced in September 2023,” said Dickinson.

Department list

Nitroshield has recently been added to the Department of Agriculture's list of products with active ingredients that can be marketed in Ireland as urease inhibitors.

The list also includes NBPT, 2-NPT, NBPT+NPPT and Maleic Itaconic CoPolymer.