During a job interview, have you ever been asked to piss for your new employer? New applicants for many of the Fortune 500 corporations are now being forced to take a drug test. In fact, 15 million will be tested this year. Drug byproducts can be detected in urine, blood, hair, external residue, and even perspiration! Drugs aren't the only things they test for; employers are using urinalysis to test women for pregnancy. Pregnant women are getting laid off or denied employment after taking such a test. Parents are spying on their children. The DOD Directive requires the military to screen all active duty members annually. If you don't want to be a victim of the drug war, this text will help you. If you are well known, this text may protect your reputation. I strongly recommended that drug users (pot smokers in particular) read this. Other drugs are covered as well, but marijuana is the main focus of this paper.


Drug tests detect drugs as well as metabolites. Metabolites are the byproducts of a substance after it has run through your system. To determine whether you will pass or not, it is important to know how much of the illicit metabolites are in your urine and how much is tested for. Table 1.2 will give you an approximation; however, it varies depending on a number of factors. Testing method and levels tested for are major factors.

1.1 Halflife of TetraHydraCannabinol:

The halflife of THC concentration ranges between 0.8 to 9.8 days. There is too much human variation to even approximate how long THC will be detected in the urine of an individual. Infrequent users with a fast metabolism will have the shortest detection time. Frequent users with a slow metabolism will have long detection times. The only way to estimate a detection time is to consider the lower and upper bounds (3-30 days), and decide based on the factors I've mentioned.

1.2 Detection times of several drugs.


Drug                             Approximate Detection Time in Urine using EMIT
------------------------------    ----------------------------------------------

Amphetamines 2-4 days Barbituates Short-Acting (ie. secobarbital) 1 day Long-Acting (ie. phenobarbital) 2-3 weeks Benzodiazepines 3-7 days Cannabinoids 3-30 days Clenbuterol PE 2-4 daysF1 Cocaine 2-4 days Codeine 2-5 days Euphorics (MDMA,psilocybin) 1-3 daysF2 LSD 1-4 days F6 Methadone 3-5 days Methaqualone 14 days Nicotine ?F5 Opiates 2-4 days Peptide hormones PE undetectable Phencyclidine (PCP) 2-4 daysF4 Phenobarbital 10-20 days Propoxyphene 6 hours to 2 days Steroids (anabolic) PE oral:14 daysF3 parenterally:1 month F3 PE Performance Enhancers F1 0.5 ng/mL by GC/MS F2 By RIA and GC/MS only. Not Detectable by EMIT. F3 By HPLC, RIA, and GC/MS. Not Detectable by EMIT. F4 8-14 days as was reported in earlier versions and was incorrect. F5 No data available yet. I expect the detection time to be long because nicotine is fat soluble. F6 Detectable by EMIT and RIA, but rarely tested. A lab will only test for LSD when specifically requested. Note: Detection times vary depending on analytical method used, drug metabolism, tolerance, patient's condition, fluid intake and method and frequency of ingestion. These are general guidelines only. + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +

Try to call in sick on test day to delay one more day if possible; it will help.

Other factors determining degree of intoxication include metabolism, tolerance, frequency of intake, fluid intake, amount of marijuana, potency of marijuana, and length of time you've been a user. If you use marijuana on rare occasions, your urine may be clean of metabolites in less than a week. There is a common and strange phenomena that occurs with chronic users. You would expect a chronic user to have the longest detection time and the smallest chance of passing. This is not always the case. A chronic user with a high tolerance will eliminate drugs quicker than an occasional user. Chronic users have tested negative after a week long binge. Lipid tissue also makes a huge difference. Skinny users not only have a faster metabolism (usually), but also lack storage for THC metabolites. Fat will cause a lag in excretion pattern, and lead to a longer detection time. You should now be able to understand why an individual's detection time for THC is so unpredictable. Many people can't even begin to estimate a detection for their own bodies, let alone the unseen, unknown body of a lost internet explorer.

There is an inaccurate program that will plot a graph of time versus percentage of THC in your system given the days you've smoked. The program is called CALC_THC.EXE and can be found on the internet. CALC_THC cannot possibly be accurate because it doesn't have any way of measuring the potency of the weed, and it leaves metabolism out of the equation. (see 14.2.3)

1.3 Positive (defined):

50 nanograms of THC metabolites per milliliter defines a "presumptive positive" by NIDA certified labs. This value was originally 20 ng/mL, but too many false positives resulted. So the level was raised to 100 ng/mL to reduce false positives. As of January 1995, the threshold was lowered back down to 50 ng/mL because drinking water would easily bring a positive below 100 ng. Be aware that these cutoffs are not universally consistent. I recently heard of a lab using a 15 ng/mL cutoff! Following is a table for cutoffs of other drugs:


DRUG                SCREENING CUTOFF            GC/MS CUTOFF

Amphetamines Class            500                    500
  Amphetamine                 500
  Methamphetamine             200
Barbituates                   200	             100
Cocaine                       150                    150
Marijuana                      50                     15
Opiates                       300
  Codeine                     300
  Morphine                    300
Phenyclidine                   25                     25

All cutoff levels are in nanograms/mL

1.3.1 Passive smoke and positives:

"Second hand marijuana smoke in a car can cause you to fail the next day" (Nightbyrd). It is possible that second hand marijuana smoke will raise someone to the 50 ng/mL level; however, *extreme* exposure is required. For instance, a closed car full of pot smokers and a non-smoker may render the non-smoker positive for both urinalysis and the hair test, provided that they are sealed in the car for a while. The Army did a case study where volunteers were put in a room pumped full of smoke for an hour, five times daily. Subjects started testing positive after the second day. The non-smoker would have to take in virtually as much second hand smoke as a smoker. Non-smokers are safe in a ventilated area, as long as they don't get a hair test. According to Clinton, simply blowing crack smoke on ones hair may cause a positive hair test. Second hand pot smoke doesn't affect the hair test results as much as crack smoke does mainly because exhaled smoke contains no THC. The only pot smoke that contains THC is the smoke that hasn't entered the lungs.

1.4 Decreasing detection times:

Increasing metabolism is probably the most effective way to decrease the time period that drugs can be detected in your system. Physical activity can increase your metabolic rate as much as two thousand percent! Nothing beats proper training taken to an extreme. A high calorie diet is the next best way to increase metabolism. Consuming mass quantities of high calorie food will increase metabolic rate by up to 10 percent. On the contrary, a malnutritious (light) diet could lower your metabolism by 10 percent. Speed (the drug) will also increase metabolism. Unfortunately, labs usually test for speed, and could get you into trouble. So exercise with intensity, and eat big.


There are four types of urine tests, a hair test, a perspiration test, and a residue test. Before continuing, I must say that this text mainly applies to urinalysis. However, I try to cover methods for beating all drug tests.

It would be helpful if people could somehow find out which test they are getting ahead of time, though caution must be taken. Asking your boss whether you're getting an EMIT or GC/MS would imply that you know too much, or seem too curious. The law doesn't protect you from unjust hiring practices, and your boss to be may refuse you employment for any reason. If simply drinking a cup of water makes the boss feel uncomfortable, the verdict may be guilty before you even take the test.

2.1 Substances that are detectable:

An assay can be developed for any drug using GC/MS. The table below indicates what can be dectected in screening tests.


                                EMIT        RIA        HPLC

Amphetamines                      Y          Y
Antidepressants                   Y          .
Barbituates                       Y          Y
Benzodiazepines                   Y          Y
Cannabinoids                      Y          Y
Carbamazepine                     Y          .
Cocaine                           Y          .
Ethanol                           Y          .
LSD                               .          Y
Methadone                         Y          .
Morphine                          .          Y
N-Acetylprocainamide              Y          .
Opiates                           Y          .
PCP                               .          Y
Phenobarbital                     Y          .
Propoxyphene                      Y          .
Steroids                          .          Y           Y
Theophylline                      Y          .

Y       = detectable
.       = not detectable
(blank) = unknown

2.2 DrugAlert:

DrugAlert is a $19.95 home test kit enabling parents to test their children. This is the most inaccurate test being used, and it's also the newest. The test kit is a small brown pad giving off an Oxy pad odor. The uninformed parent wipes the child's clothes, books, and anything belonging to the child. Then the pad is sent to Barringer Technologies via mail. (Note that it's a felony to send controlled substances through the mail. If the sample is positive, Barringer Technologies is knowingly urging parents to break the law). The lab puts the pad in a microwave looking machine, which detects residue from seven different illicit drugs. The child fails the test if s/he uses drugs, or unknowingly comes in casual contact with a drug user. Simply borrowing a pencil from a classmate that uses drugs will pass enough residue to render a positive test and an angry parent. When we have statistics like - 90% of all paper currency shows traces of cocaine, this test kit is quite foolish. Your only defense is to continually clean everything you touch with disinfectants.

2.3: Gas Chromatography: Defined by Thein and Landry:

Gas chromatography uses a separation technique to divide the urine extracts into the component parts. An inert gas carries the urine through chromatographic columns, and the samples are separated by their boiling temperature and by their affinity for the column. Compounds are identified by separation time, called retention time. The retention time is unique and reproducible for each drug in a given chromotographic column.

2.6 Gas Chromatography / Mass Spectrometry:

Defined by Thein and Landry:

The most precise procedure for detection of banned substances is a combination of GC and MS. Gas chromatography/mass spectrometry is a two-step process, where GC separates the sample into its constituent parts, while MS provides the exact molecular identification of the compounds. Compounds are separated by GC and are then introduced, one at a time, into a mass spectrometer. As the sample constituents enter the MS, they are bombarded by electrons, which cause the compound to break up into molecular fragments. The fragmentation pattern is reproducible and characteristic, and is considered the "molecular-fingerprint" of a specific compound. Gas chromatography/mass spectrometry is considered to be the most definitive method for confirming the presence of a drug in the urine and is approximately 100 to 1,000 times more sensitive than TLC. Selective ion monitoring has been used to improve the GC/MS results. This procedure is the most costly, averaging approximately $200 per sample to test.

The GC/MS is typically used to confirm "positive" EMIT test results. GC/MS will indicate precisely what chemical is present. This is necessary because the EMIT will only indicate whether something similar to what's being tested was found. The GC/MS is difficult and more costly, which is why the EMIT is given first. (Hewlett Packard produces the GC/MS equipment, including computer, for about $50-75k depending on options.) Abstinence and substitution are the only ways to defeat the GC/MS test. GC/MS is very precise when done right. However, it's still subject to human error. For example, if the equipment isn't cleaned well, the previous test sample could get mixed with the next sample. According to Dr. Edward Cone, the GC/MS is 99 percent accurate; not very accurate on a large scale when you realize that 10 thousand out of every million will get false results. (more on accuracy in section 3).

2.5 Hair testing:

When THC metabolites are in the blood, they go through the blood vessels in the head, and get filtered through the hair. THC metabolites remain in the hair as a permanent record. The hair test costs several hundred dollars ($150-$300) and is rarely given because urinalysis is cheaper (approximately $65) and more accurate. (The hair test equipment and setup goes for over a million). According to Jeff Nightbyrd, hair tests are "widely used in the casino industry." They cut 50 strands of hair from the scalp, and send it in to the testing lab where they liquefy it. "A hair sample is dissolved in a series of solvents which extract the drug metabolites and then are analyzed via GC/MS." It can take several hours to days just to extract metabolites. Average hair grows 1/4 inch per month. Typically they just use hair one and a half inches from the scalp; though some labs will take enough to test for up to 3 years. The liquid is run through the most sensitive GC/MS machines available, and can detect as little as 1 ng/mL! The hair test discriminates in that detection is easier in dark hair. Colored people may be discriminated against further because melanin is in their hair, which can be mistaken for THC. However, there is conflicting data as to whether melanin can be detected as THC. Psychemedics Corporation has a PDT90 kit for $75. This home test kit is for parents that want to chop off a lock of their child's hair to find out what drugs s/he is using. Kids- lock your bedroom doors at night if your parents don't trust your judgment on the drug issue.

Beating the hair test is extremely hard, and there are false positives. Bleaching or dying your hair is rumored to work, but it doesn't. I imagine you can shave every hair on your body and claim that you're a swimmer. According to NORML, Aloe Rid by Nexus is a shampoo that will aid in testing negative. Aloe Rid is available only in salons. Healthy Hair, from Sampson Health Products, is another shampoo designed to beat the hair test. Healthy Hair is sold in retail stores throughout Las Vegas. Keith Thrash from Sampson Health Products recommends precleansing with Aloe Rid prior to using Healthy Hair. Healthy Hair is used in the morning and before going to bed. Each session takes 20 minutes. According to Steve at Sampson Health Products, two out of a thousand people failed the hair test when using Healthy Hair. Byrd Labs is currently developing a shampoo to defeat the hair test. Some have suggested treating hair with oil because THC is oil based and oil soluble. However, there is no proven way to beat the hair test, so it's all heresay and guessing at this point. (If anyone has any success with the shampoos or the swimmer excuse, please let me know). Swimming and washing your hair removes toxins, and Keith Thrash recommends doing both as much as possible. Fortunately, the hair test cannot be used alone as evidence because there are no forensic standards. It can only be used when substantiated by other evidence. Also, there are no intoxication standards. I believe if you tested positive for the hair test that you would probably have a good chance of fighting it. (BlockBuster Video uses the most up-to-date equipment, and passing such a test can be difficult). It takes several months of precleansing to beat the tests given by Psychemedics.

2.6 High Performance Liquid Chromatography:

Usually used to detect anabolic steroids. Defined by Thein and Landry:

High-performance liquid chromatography is similar to GC, except a liquid carries the sample through the chromotographic columns and the columns are not placed in a heated compartment. High-performance liquid chromatography is both sensitive and specific, and it is simpler and faster than GC. Gas chromatography and HPLC are reliable methods for screening, and they allow for simultaneous determination of a wide variety of different compounds. High-performance liquid chromatography is used to screen for urinary caffeine levels and has been used to confirm the positive results obtained from other screening techniques. Some steroids can be analyzed with this technique, whereas HPLC and GC lack appropriate sensitivity to detect beta-adrenergic blockers.

2.7 ImmunoAssay:

This procedure is best described in Thein and Landry's word's:

Immunoassays use antigen-antibody interactions to detect illegal substances. Antibodies that bind selectively to certain drugs or drug metabolites are chosen, and the sensitivity and the specificity of this test are only as good as the antibody chosen. The binding is proportional to the amount of drug in the urine and can be detected through enzymes, radioisotopes, or fluorescent compounds. With this technique, very small amounts of drug can be detected in a very small amount of urine, although this test may not differentiate between specific drugs within a class of drugs. Immunoassay has yielded false-positive results with some decongestants and nonsteroidal anti-inflammatory drugs. Radiommunoassay (RIA) and fluorescence polarization immunoassay (FPIA) are specific IA techniques currently being used. Radioimmunoassay can detect some 17 alpha-methyl, 17 alpha-ethyl, and 19-nortestosterone steroids despite its low specificity. Immunoassay is both more sensitive and more specific than TLC.

2.7.1 Radio ImmunoAssay (aka AbuScreen):

"Of all the screening methods . . . (EMIT, TLC, RIA), RIA is the best method available." The RIA test is applied the same way as the EMIT. "The only difference btw RIA and EMIT is that RIA uses radioactive iodine as the detection mechanism rather than an enzyme NAD/NADH rxn which is detected by a scintillation counter" (anon1). The scintillation counter is used to measure the amount of radioactive particles present. Radioactivity is inversely proportional to metabolite level. RIA tests are a little more sensitive than the EMIT, and harder to beat. The most known user of the RIA test is the US government; in particular, the US military. The EMIT is more common because RIA produces radioactive waste, and radioactive waste is difficult to deal with. The US government uses RIA because a "company gives the government the instrumentation free in exchange for buying their reagents (reagent rental contract)." Some non-government labs use the RIA, so don't be surprized if your pre-employment screening is a RIA rather than an EMIT.

2.7.2 Enzyme Multiplied Immunoassay Technique:

The EMIT is the cheapest, easiest to perform, and most common; also the easiest to fail. It's the easiest to pass if you're well informed (ie. reading this text). Most pre-employment screens will give you the EMIT first; though some businesses will surprise you with a GC/MS test up front (discussed later). Unfortunately, there is no standard procedure to expect. (One who has read this file and is well informed may still fail because of the random nature of drug testing labs.) If you don't know which urinalysis will be administered, focus on beating the EMIT. If you pass the EMIT, you're off the hook. If you fail the EMIT, they'll give you the confirmation GC/MS test, which is extremely sensitive. Lewis Maltby, director of the Workplace Rights Office, said the EMIT test is wrong 25 to 30 percent of the time.

2.7.3 Fluorescence Polarization ImmunoAssay:

No information yet available on this test.

2.8 PharmChek:

A band-aid type patch is worn for a week or more to absorb perspiration. If illicit drugs are used during the time the sweat patch is worn, the patch will be positive when the lab tests it. The patch has a tamper-proof design - no thanks to 3M, who manufactures the patches. (Don't sweat it; we'll find a way to tamper with the silly patch) PharmChem Laboratories Inc. created the patch, and got market approval from the FDA. The FDA permitted the patch for detecting cocaine, amphetamines, and opiates. They are working on getting FDA clearance to use the patch to test for marijuana and PCP. The FDA already gave permission to use it in the workplace. PharmChem will sell the patch to law enforcement and drug rehabilitation agencies in 1996. Accuracy of the sweat patch remains unknown. No one has disclosed any information regarding how inaccurate this test is. Bad lab procedure is a very big problem in the testing industry, and it's hard to tell how prone to human error the sweat patch test is.

2.9 TestCup:

No details available yet. This new test by Roche involves urinating into a cup, where the cup has an indicator on the side displaying what drugs are positive.

2.10 Thin Layer Chromatography:

TLC "involves adding solvent to urine to extract drugs and then comparing color spots on a TLC plate to that of a standard" (Nightbyrd). Accuracy is very poor, and this test is rarely used. A TLC kit called ToxiLab is available. This kit has been abandoned for the most part, since EMIT has been improved. Fortunately, it's not used for confirmation anymore. Thein and Landry's definition:

Thin-layer chromatography testing is based on the differences in the migration rate of various substances through a porous supporting medium. The degree of migration and the color are characteristic of certain drugs. Thin-layer chromatography can demonstrate the presence of a drug, but this procedure cannot specify the quantity of drug present. This technique is both time consuming and nonspecific, and provides only a positive or negative response. Thin-layer chromatography is capable of detecting only a limited number of substances 12 to 24 hours after ingestion, resulting in a high number of false-negative results.


The accuracy of drug testing is an area where I've decided to neglect all statistics. Those who oppose drug testing provide numbers indicating a high level of false positives. Those who favor drug testing provide numbers indicating high levels of accuracy. The fact is that accuracy varies widely from lab to lab. Generally speaking, NIDA labs are accurate. Clinton writes:

NIDA (The National Institute of Drug Abuse) is the government organization responsible for regulating the drug-testing industry. The vast majority of urine drug screens done these days conform to NIDA specs, and ALL testing associated with the government (Department of Transportation, etc.) complies with the NIDA standard. It is NIDA that decides what the "safe" cutoffs are to avoid false positives.... Despite what you might hear on the net, urinalysis, if done correctly, is a very accurate scientific procedure. I know of no labs that simply report the results of the initial EMIT screening without confirming the sample on GC/MS. The fact is, labs WANT you to test negative, because then they only have to run an EMIT test on your urine (a few cents). If you test positive, they must then confirm the positive result on GC/MS, which is considerably more expensive. . . . Incidentally, the machine which tests the hair is a relative of the GC/MS, but is FAR more precise. It can accurately detect levels of THC in a solution that are below 1 ng/mL!

CAP (College of American Pathologists) also certifies laboratories the way NIDA does. NIDA keeps it's labs in check by sending positive and negative double blind samples. Lab personnel does not know what samples came from NIDA. If the lab results are wrong, NIDA may take away the labs certification. Only labs that perform the GC/MS on site can be NIDA certified. Labs that send samples to another laboratory for GC/MS confirmation are ineligible for NIDA certification. "Drug testing when done properly with all required controls and confirmation procedures is very accurate and reliable" (anon1).

Not all labs are NIDA/CAP certified. Some labs do not properly and thoroughly clean the GC/MS equipment. Some labs don't even do a GC/MS confirmation! Some labs use cheap alternative methods to reduce expenses.

Many human errors occur in labs and cause inaccurate results. Some are careless or irresponsible errors, and some errors are accidents. Human error can ruin the results of ANY test, screening or confirmation GC/MS.

The only lab you should be concerned with is the one that is testing you. Only Federal jobs require NIDA standards. Your typical private employer may use any lab s/he chooses, which would very likely be the least expensive. Businesses don't always choose NIDA labs that follow-up a positive screening test with a confirmation GC/MS.

3.1 Procedures used:

In the workplace, an EMIT screening is typically used, with a CG/MS confirmation if the EMIT is positive. However, this is not a rule; employers can, and some do, use unusual procedures. Some employers use the RIA, and some use the hair test. The government uses RIA. They may or may not supervise the subject. Olympic athletes must be monitored by courier after a competition. The courier stays with the athlete until the athlete urinates, with a time frame of up to sixty minutes.

3.2 False positives:

No laboratory process is completely free from error. The GC/MS test is virtually error free, but the EMIT is far from accurate. There are some false positives you should avoid if you're getting an EMIT test. Take this seriously; false positives run high. If you know that there will be a GC/MS confirmation test, you can disregard this section. It would be too lengthy to list all of the false positives here. Jeff Nightbyrd's "Conquering the Urine Tests" pamphlet lists a majority of the false positives in detail. (If you are clean, and want to get back at the testing industry for conducting these absurd tests, and know that there will be a confirmation test, you could consume several false positives. This would force labs to pay for the high priced GC/MS test, eventually drive up test expenses. You will still pass the test as long as you didn't use any true positives.)

3.2.1 Ibuprofen:

Ibuprofen is a common pain reliever that (even in low dosages) used to cause a false THC positive on the EMIT test. The EMIT has been changed to use a different enzyme to eliminate false positives due to Ibuprofen. Ibuprofen in very high doses will still interfere with both the EMIT and the GC/MS. There is some conflicting data here because some sources say that the GC/MS tests can distinguish between Ibuprofen and THC (as well as other over-the-counter drugs).

3.2.2 Cold remedies, pain relievers, hay fever remedies, & diet pills:

Decongestants and diet pills result in false positives for amphetamine use in one third of the test samples given to 40 of the countries leading laboratories. There are roughly 300 over-the-counter drugs that cause false positives on the EMIT.

3.2.3 Antibiotics:

Certain antibiotics (like Amoxicillin) are claimed to cause a positive for heroin or cocaine. My expert source was unable to verify this, so I regret that there is some uncertainty here.

3.2.4 Melanin (black skin):

Melanin is the brown pigment that protects your skin from UV rays. It was raised as a discrimination issue in the 1980's, and argued that melanin's molecular structure is similar to that of a THC metabolite. Subsequent research revealed flaws in the data. Melanin was found to have no effect on THC metabolite testing.

3.2.5 DHEA:

DHEA taken by AIDS patients will cause a false positive for anabolic steroid use.

3.2.6 Dental treatment:

Caine products (like novacaine) used in dentistry have been known to cause false positives for cocaine.

3.3 True positives (legitimate):

Some legal products actually contain small amounts of illegal chemicals. All tests, including the GC/MS, will test you positive because the metabolites derived from the true positive are identical to the metabolites of the illegal drugs. One exception: poppy seeds will not cause a positive GC/MS (explained below).

3.3.1 Poppy seeds:

Poppy seeds, usually on breads, contain traces of morphine, and lead to positives for opiates. According to Dr. Grow, eating a pastry filled with poppy seeds will bring results showing that you are a *high level* opiate user. Harold Crossley, a nationally known chemical dependency expert, said you would have to eat 100 poppy seed bagels to score a positive on a drug test. When taken into account that very few poppy seeds are sprinkled on bagels, you can see that poppy seeds from a hundred poppy seed bagels will easily fill a single large pastry. Purim cookies, a Jewish food known as Hamantashen, may have five to six tablespoons of poppy seeds. A couple Purim cookies may cause a positive test. Poppy seeds can be distinguished from illicit drugs on the GC/MS test. Although poppy seeds have the same metabolites as opium, these metabolites are shown to have different patterns when viewed with the GC/MS.

3.3.2 Testosterone supplements:

Orchic extract (found in bull's balls) will give a positive for anabolic steroid use. It is a legitimate substance that causes the test to imply that you abuse steroids.

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