So I had quit smoking bud for a month when I was called for a random drug test. Before I went, I took an over the counter test for marijuana and passed it. Then I went to take the test...I had trouble filling up the cup and had to drink a lot and try three times to do it. Well the following day, I was called back to do it again because the sample was too diluted. I went and did it again and then took another over the counter test to make sure I was clean and passed it with two very dark lines. I took this test on Friday and had to take another test for a new job on Monday. I was called on Tuesday and informed that I did not pass the test I took on Friday it was positive for marijuana. I don't understand how I could pass two over the counter tests and not pass that??? Now I am stressing that the test I took on Monday will be positive and I won't have a job. Is there any chance that I will pass the pre employment test I took on Monday? I havent even smoked for over a month...I would appreciate any insight on what happened?
The tests that are conducted by the companies analyzing your urine typically use two methods of detection, one being an immunoassay and the other is a confirmatory LC/MS/MS or GC/MS. An immunoassay uses antibodies that recognize the active component of marijuana (THC) to a certain detectable level. If it comes back positive, they will run a confirmatory (much more highly specific and sensitive method) gas chromatograph/mass spectrometry of your urine along with a standard to determine the levels down to 20ng/mL (accounting for possible 2nd hand inhilation). These tests can run up to several hundred dollars but are much more sensetive at detecting the drugs in your urine than over-the-counter products. As such, it's not surprising that the OTC product you used came up negative twice and the actual urine tox screen came back positive. Since you either have the job or not at this point, it's best to kick back on your weed smoking adventures until you land a job and determine if they require random drug tests. Hope this helps.
my boyfriends been testing about one month and his marijuana levels are going up and down, why is that? and some of his test will be neg. and then the next three he took were extremely high...whats going on? he swears hes not smoking...