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.
This test can identify specific substances within the urine samples. Even if a particular drug is detected, if the level is below a certain threshold, the test result is reported back to the commander as negative. DoD labs are equipped to test for marijuana, cocaine, amphetamines, LSD, opiates (including morphine and heroin), barbiturates and PCP.