EFSA opinion on four substances used to decontaminate poultry carcasses

EFSA has carried out an assessment on whether there is any increased bacterial tolerance and resistance to antibiotics from the use of four antimicrobial substances used to decontaminate poultry carcasses¹. The EFSA Panel on Biological Hazards (BIOHAZ) concluded that, despite a long history of use, no published data exist to indicate that the four substances, within the proposed conditions of use, will lead to increased bacterial tolerance to these substances or to increased resistance to therapeutic antibiotics and other antimicrobial agents. The Panel also encouraged further research on the likelihood of an increase in bacterial tolerance to these types of substances, and the possibility of their resistance to therapeutic antibiotics and other antimicrobial agents.

The BIOHAZ Panel noted that there was some evidence indicating bacterial tolerance to other antimicrobial substances or biocides² which were not subject of this Opinion. However, these data were either based on laboratory experiments which do not always mirror “real-life” situations or resulted from the improper use of biocides.

EFSA delivered several opinions in 2005 and 2006 in relation to these four antimicrobial substances which looked at both the safety of using them on food and their effectiveness in killing or reducing bacteria. In evaluating the four substances, EFSA’s Panel on additives, flavourings, processing aids and materials in contact with food(AFC) concluded that, based on the data available, there was no safety concern, within the proposed conditions of use. For its part, the BIOHAZ Panel looked at the effectiveness of one of the four substances, peroxyacids, and said that, owing to lack of sufficient data available to the Panel, including those submitted by the applicant, it was unable to say if these substances effectively killed or reduced bacteria on poultry.


¹ Chlorine dioxide, acidified sodium chlorite, trisodium phosphate and peroxyacids. Such substances are presently in use in the USA to kill or reduce the number of bacteria, such as salmonella or campylobacter on poultry. At present, no such substances are authorised for use in the EU but permission may be given under EU legislation (EC Regulation No 853/2004) when preceded by a thorough scientific evaluation.

² Chemicals used for eliminating pests, weeds, fungus etc., especially a pesticide, herbicide, or fungicide.

Summary of the Scientific Opinion of the BIOHAZ Panel:  Assessment of the possible effect of the four antimicrobial treatment substances on the emergence of antimicrobial resistance

Following a request from European Commission (DG SANCO), the Panel on Biological Hazards was asked to deliver a scientific opinion on the possible effect of four antimicrobial treatment substances on the emergence of antimicrobial resistance.

The scope of this opinion was to assess the possible development of antimicrobial resistance when chlorine dioxide, acidified sodium chlorite, trisodium phosphate and peroxyacids are applied for poultry carcasses decontamination. For the purpose of this opinion, the terms “acquired reduced susceptibility” to the substances used for the removal of meat surface contamination and “resistance to therapeutic antimicrobials” were used. Therefore, acquired reduced susceptibility to the four substances used for the removal of meat surface contamination as well as to other substances including therapeutic antimicrobials has been considered. Abattoir was the end-point of the present scientific opinion.

The BIOHAZ Panel concluded that despite a long history of use, there are currently no published data to conclude that the application of chlorine dioxide, acidified sodium chlorite, trisodium phosphate or peroxyacids to remove microbial contamination of poultry carcasses at the proposed conditions of use will lead to the occurrence of acquired reduced susceptibility to these substances. Similarly, there are currently no published data to conclude that the application of chlorine dioxide, acidified sodium chlorite, trisodium phosphate or peroxyacids to remove microbial contamination of poultry carcasses at the proposed conditions of use will lead to resistance to therapeutic antimicrobials.

Uncertainties originate from the facts that acquired reduced susceptibility to some biocides other than those in question was found followed improper use of biocides. In addition, most of the evidence on acquired reduced susceptibility to some biocides other than those in question was derived from laboratory-based experiments.

The Joint AFC/BIOHAZ guidance document on the submission of data for the evaluation of the efficacy of substances for the removal of microbial surface contamination of foods of animal origin should be amended. The BIOHAZ Panel recommended that any data on the potential of occurrence for acquired reduced susceptibility to biocides and/or resistance to therapeutic antimicrobials should be included. Research on the likelihood of emergence of acquired reduced susceptibility to substances used for the removal of the microbial surface contamination of foods of animal origins and other foods and resistance to therapeutic antimicrobials should be encouraged.