People have reported waves of negative side effects from using synthetic marijuana products that can last hours or even days. Stick with the real deal, at least you know what you're getting yourself into.
30 days
never!
a few seconds.
Spice leaves your system in about two days.
2-3 weeks
a long fcuking time! seems like hours!
Synthetic Mobil 1 oil last in sealed container has a shelf life of five years.
until you clean the pipe
After opening and heating once how long does synthetic urine last
If by synthetic marijuana you mean spice, it is made by picking random plants, drying them and then spraying them with a bunch of crazy chemicals. It's nothing like marijuana and has many serious side effects. Instant side effects may include seizures. There are too many long term side effects to list but neurological damage is a guarantee.
Oil last forever but oil does get dirty. Synthetic oil like conventional oil does get dirty. You can extend your oil changes slightly if you synthetic oil but no more than two or 3000 miles.
There is no conclusive evidence of negative long term side effects associated with the use of marijuana. The euphoric effects of marijuana only last up to three hours.