Delta-8-tetrahydrocannabinol (Δ8-THC) provides similar therapeutic effects to its isomer delta-9-tetrahydrocannabinol (Δ9-THC), but it presents milder psychoactive activity. There are no recent studies reporting data on Δ8-THC clearance and pharmacokinetic specifically: usually researches are related to THC-9 and other major cannabinoids. 
Nevertheless, these two isomers of THC have similar chemical structure, thus related metabolites and for this reason the time that the molecules stay in human body will be comparable.
The amount of time it takes for Δ8-THC to be completely cleared from the body depends on various factors like biological age, genetic and metabolism, dosage used, method of consumption, frequency of use, supplements and medications used.  For instance some people are capable of metabolizing faster than others and the metabolism of older people is generally slower than younger ones. Once ingested, Δ8-THC is converted into 11-hydroxy- Δ8-THC by hepatic cytochrome P450 enzymes (in particular CYP3A4). Following subsequent metabolic conversions though dehydrogenase and glucuronidase enzymes, the final metabolite 11-nor- Δ8-THC-9-carboxylic acid glucuronide (Δ8-THC-COOH) is excreted in the urine. 
If medicaments requiring P450 enzymes to be metabolized are used while Δ8-THC consumption, the cannabinoid will stay longer in our system because the metabolic rate will be slower. Residual levels of Δ8-THC and its isomers are maintained in the body for long time, varying from 1.3 days for an infrequent user to 5 -13 days for a frequent user.  An habitual consumer will accumulate cannabinoids in fat cells and these quantities will prolong the time of these molecules to be cleared completely from the body.
It should be noticed that depending which kind of tests and which biological fluids are analysed, it is possible to detect THC metabolites at various time points: in urine Δ8-THC could be detected up to two months and in hair follicles it takes around three months to completely clear Δ8-THC residues. More studies regarding Δ8-THC pharmacokinetic should be done in order to improve the actual knowledge about Δ8-THC concentrations in various biological matrices and clearance from human body for an appropriate application of pharmacotherapies, evaluation of forensic cases and drug testing.
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