Antecedents and objectives:

Poppy seeds, whose consumption alone or contained in certain foods is considered safe in Spain from the toxicological point of view, have different amounts of opioid alkaloids that can cause «false positive» results in the analysis of drugs of abuse in urine samples, such as those routinely performed, among other groups, on Armed Forces personnel. Following a case detected at the Institute of Toxicology of the Defense of a positive result to opiates in a person who reported the consumption of a bread containing poppy seeds, it was proposed to carry out a study of this problem and how to approach it from the analytical point of view.

Material and methods:

We studied how the consumption of this bread affected to two volunteers, analyzing urine samples by both screening and confirmation methods, and was supported by a literature review using different specialized databases in reference to the interference of the consumption of poppy seeds and products containing them with the analysis of drugs of abuse in urine samples.

Results:

Using the 300 ng/ml cut-off point, 62% of the screening tests were presumably positive to opiates. In certain samples the confirmatory analysis identified codeine above the established detection limit. The literature supported these results.

Conclusions:

In order to deal with this problem analytically, it has been proposed to increase the confirmation cut-off level in the analytical confirmatory technique. In addition, the detection of thebaine as a specific biomarker for poppy seed consumption and/or the increase of the cut-off point to 2000 ng/ml has been proposed as other possible measures to be implemented.