Antibiotics monitoring in Europe is inadequate

The microbial screening methods to detect antibiotics residues in meat are inadequate in many European countries. The methods do not detect all instances of contamination with antibiotics, and they often do not indicate whether the maximum residue limit has been exceeded. This was the theme of an article written by Dr. Mariel Pikkemaat, a researcher at RIKILT (Wageningen UR) in the latest edition of Analytical and Bioanalytical Chemistry.

‘At the present time, the residue tests do not provide a reliable picture of the antibiotic problem in livestock in various European countries, because the tests in many countries are substandard’, says Pikkemaat. This was the conclusion of a study conducted by the European reference lab (located in France) that sends meat samples for testing to the national monitoring labs in Europe. ‘One-third of these laboratories were unable to adequately detect the presence of antibiotics, even though the concentrations were two to four times higher than the maximum residue limit', asserts Pikkemaat.

Slaughtered animals are tested for antibiotics by culturing a sample of kidney tissue or meat in a medium with sensitive bacteria. If the bacteria have grown the next day, then the meat is safe; if they have not grown, then antibiotics may be present in the meat. Suspicious samples are then subjected to chemical tests to ascertain the identity of the antibiotic and its concentration. These chemical tests are very advanced and precise, says Pikkemaat. ‘A great deal of money is invested in these tests. Distressingly, the initial screening, which creates the basis for the residue monitoring system, is inadequate in much of Europe.'

Pikkemaat has advised the European Union to improve the screening of slaughtered animals. ‘Officially, the French reference lab is supposed to raise the matter with the European Union, but until now this is not taken place very decisively.’

According to Pikkemaat, the Food and Consumer Product Safety Authority (VWA) does a good job of monitoring antibiotics in slaughterhouses in the Netherlands. The VWA does this with the aid of an improved microbiological screening method that was developed by RIKILT on behalf of the government.

The RIKILT method uses various culture media and various types of bacteria for each medium. ‘We can detect virtually all residues. The disadvantage of this more complex method is that it allows more space for so-called false positives, i.e. meat samples that have been incorrectly identified as hazardous.’ The method tests for more than 50 antibiotics. / Albert Sikkema