Transfer von ?9-Tetrahydrocannabinol (?9-THC) und anderen Cannabinoiden aus ?nutzhanfhaltigen Futtermitteln in die Milch von Kühen

"Transfer of ?9-tetrahydrocannabinol (?9-THC) and other cannabinoids from feed containing industrial hemp ?into the milk of cows"

Interest in the use of industrial hemp (legally cultivable hemp with a maximum tetrahydrocannabinol content ?of 0.3%) is growing, and in recent years many novel hemp products have been launched - including animal ?feed. Industrial hemp contains cannabinoids. Some of these have psychoactive effects in humans and animals ??(e.g., ?9-tetrahydrocannabinol, ?9-THC) or other pharmacological effects (e.g., cannabidiol, CBD). So far, it ?was unclear to what extent these cannabinoids are transferred from feed containing industrial hemp into ?products of animal origin and whether this poses a risk to the consumer.
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In the present study, "Transfer of ?9-tetrahydrocannabinol (?9-THC) and other cannabinoids from feed ?containing industrial hemp into the milk of cows", the results of a feeding trial with industrial hemp silage in ?ten lactating dairy cows are presented. Initially, part of the corn silage in the animals' feed ration was replaced ?for seven days by industrial hemp silage made from the entire hemp plant (GP-silage, very low cannabinoid ?concentration). This was followed by six days of partial replacement of corn silage with industrial hemp silage ?consisting only of leaves, inflorescences and seeds of the plant (BBS silage, higher cannabinoid concentration). ?Feeding was done in two dosages (group 1: low industrial hemp content; group 2: high industrial hemp ?content). During the experiment, milk and blood samples were obtained and the vital parameters and behavior ?of the cows were recorded. Analysis was performed by a liquid chromatography-tandem mass spectrometry-?based method (HPLC-MS/MS), which allowed differentiation between psychoactive ?9-THC and its non-?psychoactive precursor ?9-tetrahydrocannabinolic acid (?9-THCA).

Transfer rates of 0.24 ± 0.04% and 0.15 ± 0.05% from feed to milk were calculated for ?9-THC and CBD, ?respectively. In different exposure scenarios calculated using the EFSA-RACE tool, several consumer groups ?exceeded the acute reference dose (ARfD) for ?9-THC when milk and dairy products were consumed and ?industrial hemp silage was used to feed dairy cows. The exceedance was most pronounced in children when ?BBS-silage was used. In terms of animal health, feeding the low-cannabinoid GP-silage resulted in no ?significant effects in cows, whereas feeding the high-cannabinoid BBS-silage resulted in significant reductions ?in heart and respiratory rates, impaired movement coordination, reddened eyes, nasal secretion, ?hypersalivation, and pronounced tongue play.?