Acidic herbicides as an alternative to glyphosate
Special features of acidic herbicides and their analysis
Nov 2023. On 16 November 2023, the EU Commission announced the re-authorisation of glyphosate for a further 10 years. The extension is subject to new conditions and restrictions. Previous votes in the relevant Committee on Plants, Animals, Food and Feed failed to achieve the required majority, meaning that the EU Commission took the decision alone.
Glyphosate is a total herbicide used in agriculture to control unwanted organisms. In conventional farming, there are a number of alternatives already in use. A possible alternative to glyphosate are the acidic herbicides. We give you an overview of the group and explain how to detect them completely.
Acidic herbicides
Acidic herbicides with known representatives such as 2,4-D, fluazifop, haloxyfop or MCPA, which are detected in vegetables, herbs and spices or oilseeds, among others, play an important role as selective growth herbicides.
Probability of findings of acidic herbicides after hydrolysis in selected products*
The special feature of these substances is that they are not only used in the form of the free acid, but also as esters. These esters, in turn, degrade to the free acid during their use. They are thus equally toxicologically relevant, together with the conjugates of the active substances bound in the plant. Therefore, these pesticides are regulated in the Regulation (EC) No 396/2005 on maximum residue levels in foodstuffs as a sum calculated and as free acid.
Analysis by hydrolysis
Analytically, the behaviour described poses a challenge, since the usual mulit-methods only detect a few esters and the free acid. However, there is the possibility of converting all esters and conjugates into the free acid via a separate method using hydrolysis and then determining them as a total residue.
Comparisons of the results have shown that the determined total residue with hydrolysis is often higher than with the determination of individual substances by a multi-method. Therefore, products for which there is already an indication of acidic herbicides or which, based on experience, show a high risk of such findings, should be analysed by a residue method that can detect the total residue of acidic herbicides after hydrolysis.
Contact us!
If you have any questions on acidic herbicides or their analysis, please do not hesitate to contact your personal account manager or our expert Johannes Jaschik directly.
*The evaluation shown in the graphic is based on test results and analysis data from Eurofins Food & Feed Testing laboratories in Germany. All data have been anonymised so that no conclusions can be drawn about individual clients. The data does not claim to be representative for the global market. Reasonable care has been taken by the publishing company to ensure that the information provided in this document is true and accurate according to the defined statistical minimum requirements. The information provided in this document is exclusively intended as an informal information for individual consideration and does not replace a quality control and risk assessment program of a food and feed producer, trader, packer or retailer, which must be tailored to the individual situation. To the extent permitted by law, the company shall not be liable for any loss, damage or expense whatsoever arising out of or in connection with this publication, directly or indirectly, including but not limited to, in contract, tort, strict liability or any other legal bases.
Eurofins Dr. Specht International GmbH
t +49 40 881 448 452
JohannesJaschik@eurofins.de
