Using environmental DNA approaches, researchers have uncovered bits of bugs and spiders left on tea leaves among samples bought in shops, Nature News reports.
Researchers from Trier University in Germany bought 40 samples of four plants — chamomile, tea, parsley, and mint — from 17 different brands. As they report in Biology Letters, they then extracted arthropod DNA from those samples. Arthropods, the researchers note, leave behind their DNA on plants when they chew on them or defecate on them. While this is typically washed off by rain or destroyed by UV light, they note that plants that are dried — like tea — could hold on to vestiges of those critters' DNA.
In their analyses, the researchers uncovered DNA from more than 1,200 arthropod species. Further, some of these bugs could be used to trace the origin of the sample, such as mint to the Pacific Northwest of the US.
This approach, they noted, could be applied to not only conservation-orient bio-monitoring but also to regulatory and customs monitoring.