How long can 1 use of marijuana be detected on a saliva drug test ?

Saliva: 1-10 days: With a single use of marijuana, thc can be detected in saliva for 1-10 days. Hair can last longest lasting of all: up to 90-120 days. Urine is the fluid usually tested, though. With a single use, thc is detectable in urine for 5-8 days.

Depends on use.: It depends on how often you use it. If you used it only once it can be detected by blood for 12-24 hours while it is detected in urine from 1-7 days. With regular use it can be detected in blood for 2-7 days and in urine anywhere from 1-100 days even if a heavy user. Age, height, weight, metabolism all are considered factors. Saliva can be 12-24 hours.