E T DRUG COURT U T I PRACTITIONER T S FACT SHEET N I THE MARIJUANA DETECTION WINDOW: DETERMINING THE LENGTH OF TIME CANNABINOIDS WILL REMAIN T DETECTABLE IN URINE FOLLOWING SMOKING R A CRITICAL REVIEW OF RELEVANT RESEARCH AND CANNABINOID DETECTION GUIDANCE FOR DRUG COURTS U By Paul L. Cary, M.S. O C PREFACE 2 The duration of the urinary cannabinoid detection window is not settled . O N science. The number of days, following the cessation of marijuana , G V smoking, necessary for cannabinoids to become non-detectable using I . L traditional drug testing methods is the subject of debate among forensic O V U toxicologists and a matter of on-going scientific research. This article makes no pretense to limit this important discussion, but rather, seeks 6 R 0 to enhance it. It is hoped that drug court practitioners will find that this 0 2 L information clarifies some of the complex issues associated with the I R P elimination of marijuana from the human body. A D Conventional wisdom has led to the common assumption that cannabinoids R O will remain detectable in urine for 30 days or longer following the use T L C E of marijuana. These prolonged cannabinoid elimination projections have R I D likely resulted in the delay of therapeutic intervention, thwarted the A E V I timely use of judicial sanctioning, and fostered the denial of marijuana T U C usage by drug court participants. N E X E , This review challenges some of the research upon which the 30-plus day N O O elimination assumption is based. Careful scrutiny of these studies should S L I I not be interpreted as an effort to discredit the findings or the authors W - N of this research. However, as our knowledge evolves, the relevancy of T A M E previously published scientific data should be evaluated anew. One fact E A R is clear—more research is needed in the area cannabinoid elimination. F N E R A K N NATIONAL DRUG COURT INSTITUTE Merely attempting to formulate cannabinoid the cutoff calibrator for ten consecutive days.” detection guidance invites controversy. Some Based upon these seemingly divergent findings, will argue that the proposed detection window it is not difficult to comprehend why judges, defined in this article is too short. Others will attorneys and other drug court professionals suggest the opposite. Still others will insist are in a quandary regarding the length of time that the scientific evidence is insufficient to marijuana can remain detectable in urine allow the establishment of such guidance. following use. The dilemma—if the scientific To some degree, each position has merit. No research seems not to be able to achieve detection window guidance, regardless of the consensus on the urinary cannabinoid detection extent of scientific support, will encompass window, how are those responsible for court every set of circumstances or all client situations. mandated drug supervision programs suppose If nothing else, the research demonstrates that to understand and resolve this issue? there is significant variability between individuals Like many other scientific and technical topics in the time required to eliminate drugs. that have been thrust into the judicial environ- These facts, however, should not preclude ment, the detection window of marijuana the development of reasonable and pragmatic is both complex and controversial, yet the guidance, supported by scientific research, for understanding of the pharmacology of this use in the majority of drug court adjudications. popular substance is crucial to the adjudication It is widely accepted that in order to instill of cases in which marijuana usage is involved. successful behavioral changes in a substance While the difficulties associated with estab- abusing population, that consequences need lishing the length of time a drug will continue to be applied soon after the identification of to test positive in urine after use are not unique renewed or continued drug use. In a drug court to marijuana, the problem is exacerbated by context, the application of judicial sanctions the extended elimination characteristics of and the initiation of therapeutic interventions cannabinoids relative to other drugs of abuse, have been needlessly delayed due to a lack most notably after chronic use. of coherent guidance regarding the length of The questions posed by drug court professionals time cannabinoids will likely remain detectable related to cannabinoid detection in urine include: in urine following the cessation of marijuana smoking. The purpose of this article is to • How many days is it likely to take for a chronic marijuana user to reach a negative urine drug provide that much needed guidance. test result? • How long can cannabinoids be excreted and INTRODUCTION detected in urine after a single exposure to marijuana? In a recent forensic publication, Dr. Marilyn How many days of positive urine drug Huestis wrote: “Monitoring acute cannabis • tests for cannabinoids constitutes continued usage with a commercial cannabinoid marijuana usage? immunoassay with a 50-ng/mL cutoff concen- • How often should a client’s urine be tested tration provides only a narrow window of to monitor for continued abstinence from detection of 1–2 days,” (2002). In a 1985 marijuana? article by Ellis et. al., researchers concluded; • How many days should the court wait before “that under very strictly supervised absti- retesting a client after a positive urine drug nence, chronic users can have positive results test for cannabinoids has been obtained? for cannabinoids in urine at 20 ng/mL or • How should the court interpret a positive above on the EMIT-d.a.u. assay 1 for as many urine drug test for cannabinoids after a client as 46 consecutive days from admission, and has completed an initial 30-day detoxification period designed to “clean out” their system? can take as many as 77 days to drop below 2 DRUG COURT PRACTITIONER FACT SHEET To one degree or another, answering these questions depends upon the ability of the court to estimate the length of time cannabinoids Study subjects with exceptionally long will likely remain detectable in urine following cannabinoid detection times (30-plus the use of marijuana by a drug court client. Thus, the cannabinoid detection window days) were just that-exceptional. becomes a determinative factor in the appro- priate interpretation of urine drug testing results for marijuana. The lack of adequate guidance has hindered the development of For those compounds with uncomplicated these standards for use in drug court. metabolic pathways or for those drugs that are not significantly retained in body storage It is important to note that while courts compartments, detection times have been may be seeking absolute answers (an exact established and generally accepted. These cannabinoid detection window), the science include urinary detection windows for drugs of drug detection in urine can only provide such as cocaine (1-3 days), amphetamines reasonable best estimates. The law is not and opiates (1-4 days), and PCP (1-6 days) always black and white; neither is science. (Baselt, 2004). For marijuana, the urine elimi- Therefore, precise “yes/no” answers or nation profile used to establish the detection exact detection windows are generally not window is more complex. It is well docu- attainable. Sensible guidance for the interpre- mented and understood that cannabinoids are tation of urine cannabinoid results by drug lipid-soluble compounds that preferentially courts, however, is achievable. bind to fat-containing structures within the human body (Baselt, 2004). This and other FRAMING THE QUESTION chemical characteristics can prolong the elimi- nation half-life of cannabinoids and extend the Simply put, the detection window is the length detection window beyond that of other abused of time in days following the last substance substances. Chronic marijuana use, which usage that sequentially collected urine samples expands body stores of drug metabolites will continue to produce positive drug test faster than they can be eliminated, further results—in other words, the number of days increases cannabinoid detection time in urine. until last positive sample. This time period is not the same as the length of time a drug will remain in someone’s system—that concept VARIABLES is, in reality, indeterminable (given that there Estimating the detection time of a drug in urine is no analytical method capable of detecting is a complex task because of the many factors the presence of a single molecule of drug in a that influence a compound’s elimination from donor’s body). The question being addressed the body. Additionally, technical aspects of the herein is not how long minute traces of mari- testing methods themselves also affect how juana will remain in a client’s tissues or fluids long a drug will continue to be detected in urine. after smoking, but rather how long those The pharmacological variables affecting the residual cannabinoid metabolites will continue duration of detection include drug dose, route to be excreted in urine in sufficient quantities of administration, duration of use (acute or to produce a positive drug test (by standard chronic), and rate of metabolism. Detection screening and confirmation testing). time is also dependent upon analytical factors including the sensitivity of the test (cutoff concentration) and the method’s specificity (the actual drug and/or metabolite that is being detected). 3 NATIONAL DRUG COURT INSTITUTE Generally speaking, the following factors The differentiation between acute (a single affect the marijuana detection window use event or occasional use) versus chronic accordingly: (persistent, long-term, continued usage) is • Drug Dose important to establishing reliable detection The higher the dose; the longer the detection benchmarks. As a result, drug court practitioners window. The percentage of psychologically should attempt to gather as much information active delta-9 THC in marijuana plant material as they can about client drug use behavior varies considerably, making dosage difficult to estimate.