Determination of aminoglycoside antibiotics in feed at cross-contamination levels

Antimicrobial resistance (AMR) is the ability of microorganisms, such as bacteria, to become increasingly resistant to an antimicrobial to which they were previously susceptible. Antimicrobial resistance is a consequence of natural selection, but is exacerbated by human factors such as the inappropriate use of antimicrobials in human and veterinary medicine. Over time, this makes antimicrobials less effective and ultimately useless.

Infections by multidrug-resistant bacteria are responsible for about 33 000 annual deaths in the European Union (EU) and, worldwide, the total number of deaths per year due to AMR is estimated to be 700.000. Moreover, antimicrobial resistance (AMR) is of growing concern, causing an estimated annual cost of €1.5 billion in the EU due to healthcare expenditures and productivity losses.

Ensuring the absence of antibiotics in feed is certainly an effective measure to curtail the emergence of AMR. A milestone is the Action Plan issued in 2015 by WHO, in which the “One Health” approach was launched. At the EU level, non-therapeutic use of antibiotics has been forbidden since 2006 and metaphylactic use, the treatment of animals when one is found to be infected, is not banned but permitted only if no alternative option is available. In this way, in the EU, total antibiotic use on average has decreased significantly over the past 5 years.

Antibiotic residues are almost always below the regulatory limits but are often still present in minute quantities in non-medicated feed. The risk that animals are not always exposed to sub-therapeutic levels of antibiotics through feed is of utmost importance. For this reason, the EU has included 24 active substances in the list of priority antibiotics to be controlled in feed (Regulation EU 2019/4) at cross-contamination level. Satisfactory results are needed serving the needs for an analytical method that can be applied within the frame of official control in EU Member States.

This work is part of the overall JRC commitment and effort to provide the EC policy makers and the Member States with robust and validated methods as reliable analytical tools for monitoring the 24 antibiotics listed in Regulation EU 2019/4 at cross-contamination levels by 2023.