From the link:<p><i>SB: The samples were stored since their excavation under homogenous conditions. The conditions in the laboratory were again homogenous and the samples were simultaneously investigated. Before the investigations, all samples were carefully washed with distilled water and alcohol. The washing water was tested and was cocaine negative. Also all chemicals were cocaine negative. The sample extracts were applied to the GC&#x2F;MS after it was carefully rinsed with chloroform, until no traces of cocaine or its metabolites were detected any more. If the amount measured were results of contamination, all samples should have been positive. However, only parts were positive.</i><p>Disclaimer: I do not know how reliable this source is.<p>Also they note:<p><i>Do these results support an established trans-Atlantic trading route between Egypt and South America that predates Columbus (1492AD)?<p>WP: No, this conclusion cannot be made from the Ulm findings.<p>Could they indicate the possibility of a distant trading route across the Pacific between South America, Asia and Africa?<p>WP: No, this conclusion cannot be made from the Ulm findings.<p>Do you favour any particular interpretation of your results?<p>WP: As the Ulm findings are gained from a few specimens of a few sites in the huge world without other contemporary background information I don’t dare to interpret them in any particular cultural context. </i>