Trait controlled by the both environment and genetic factor. Usually, multifactorial traits outside of illness result in what we see as continuous characteristics in organisms, especially human organisms such as: height, skin color, and body mass.
I recently took a drug test for a job. I tested positive for opiates in my urine. I do not and have never taken drugs of any sort other than alcohol. I dont take any prescription drugs, how is it possible that this happened. I hade consumed some beer about12 hours before the test.
Assuming that you'll be specifically tested for Oxycodone/OxyContin, you can fail a urine test for 3-4 days after your last dose. This will be slightly shorter for a saliva test. It's not clear what the detection time would be for a standard opiates test.