Occurrence of chloramphenicol in cereal straw in north-western Europe

ABSTRACT

Two surveys are presented of straw analysed for naturally occurring chloramphenicol (CAP), a drug banned for use in food-producing animals. In the first study, CAP was analysed by LC-MS/MS and detected in 37 out of 105 straw samples originating from the Netherlands, France, the UK, Germany and Denmark. The highest level found was 6.3 µg kg⁻¹, the average 0.6 µg kg⁻¹ and the median 0.2 µg kg⁻¹. The second study included a method comparison between ELISA and LC-MS/MS and a survey of CAP in cereal straw sampled at farms in all areas of Sweden. A total of 215 samples were screened by ELISA and a subset of 26 samples was also analysed by LC-MS/MS. Fifty-four of the samples contained more than 1 µg kg⁻¹ CAP and the highest level found was 32 µg kg⁻¹ (confirmed by LC-MS/MS). The highest contents of CAP in this study were allocated to the Baltic sea coast in the south-eastern part of Sweden (the county of Skåne and the Baltic Sea isle of Gotland). These results indicate a high incidence of CAP in straw in north-west Europe and have a severe impact on the enforcement of European Union legislation.

KEYWORDS:

• Chloramphenicol
• animal feed
• bedding
• straw
• survey
• LC-MS/MS
• ELISA

Acknowledgements

This project was financially supported by the Dutch Ministry of Economic Affairs, Agriculture and Innovation (project 1207295501).

Disclosure statement

No potential conflict of interest was reported by the authors.