Detection of Illicit Drugs in Drivers

Transcription

1 Detection of Illicit Drugs in Drivers J. M ichael W alsh, Betty J. Buchan, and Paul E. Leaverton In com parison w ith the alcohol/driving literature, relatively little inform ation is available regarding the true incidence and prevalence o f illegal drug use in driving accidents. A large n um ber o f laboratory and sim ulator studies have been conducted exam ining the effects o f drugs on the behavioral skills required for driving. In general, research indicates drugs can affect driving skills in m any w ays, and that the m agnitude o f the effect is dependent on a variety o f factors, including: D rug, dose, age, sex, w eight o f the subject, prior experience w ith the drug, behavioral tolerance, etc. (Transportation Research Board, N ational R esearch Council Report, 1993). The two principal problem s in assessing the impact o f illegal drug use on driving have been a) the lack o f routine toxicology requirem ents for accident investigations, and b) the unavailability of drug detection devices/assays to rapidly test for illegal drugs. Until recently such devices were lim ited to highly specialized forensic laboratories. In 1983, the W orld Health Organization (W illette and W alsh, 1983) pointed out that the full im pact o f drugs on traffic safety was unknow n, and unfortunately this rem ains essentially true today. O ver the last decade, however, data has em erged w hich provides some insight as to the overall extent o f the problem. W illiam s et. al. (1985) reported on a high risk sam ple o f 440 young m ale auto drivers killed in California traffic accidents w here blood specimens collected from these drivers indicated 70% contained alcohol and over 40% contained other drugs. Soderstrum, et. al. (1988) found that of 1023 patients adm itted to T he M aryland (Baltim ore) Shock-Traum a Unit, 34.7% had very recently used cannabis (i.e., greater than 2 ng/ml tetrahydrocannabinol in serum) and 33% had BA C 's greater than loomg/dl. Lindenbaum, et al (1989) at the Einstein Traum a Center (Philadelphia) found 54% o f adm issions positive for cocaine, 37% positive for cannabis, 35% positive for alcohol, 10% barbiturates, and 7% benzodiazepines. In a collaborative effort, the N ational Institute on Drug Abuse [NIDA] and the National Transportation Safety B oard [NTSB] (1993) conducted an investigation o f fatal-to-the-driver trucking accidents in eight states over a one-year period. Com prehensive drag screens on blood specimens collected from 168 fatally injured truck drivers indicated that one or m ore drugs were detected in 67% of the drivers and 33% o f the drivers had -485-

2 detectable blood concentrations o f psychoactive drugs or alcohol. The m ost prevalent drugs were cannabinoids and ethanol (each found in 13% o f the dead drivers), cocaine w as found in 8% o f the cases, and am phetam ine-like substances in 7%. In a study conducted in M em phis, Tenn. (Brookoff, et.al. 1994) individuals arrested for reckless driving w ho were not apparently im paired by alcohol [no odor of alcohol or tested negative by breath analysis or both] were tested with onsite urine drug-testing devices for m arijuana and cocaine at the scene o f the arrest with 59% testing positive (18% for both drugs, 33% for m arijuana alone, and 20% for cocaine alone). H ow ever when the specim ens were reanalyzed in a forensic laboratory, results indicated that the particular on-site device used [DSSI -M icroline] had produced unacceptably high false positive and false negative results for marijuana. T he availability o f new technologically advanced on-site drug-testing devices w hich are capable o f providing im m ediate accurate and reliable results provides a unique opportunity to effectively apply this technology in traffic safety and the enforcem ent o f drugs and driving laws. M ost states have the legal m eans (established by law) to require drivers suspected o f driving under-the-influence o f drugs to subm it to a drug test but it is rarely used prim arily because crim e-lab testing is not practical w ithin the scope o f existing w orkloads and priorities. T he principal goals o f this project were: 1) to determ ine the extent to w hich potentially im pairing drugs are found in drivers w ho fail to pass a roadside sobriety test, 2) to conduct a field evaluation o f rapid on-site drug testing devices to determ ine the m ost accurate, efficient, and cost-effective device available, and 3) to determ ine w hether it w as feasible to integrate this technology into police operations. O ur aim w as to obtain specim ens from 300 D U I suspects and analyze them on several new im m unoassay devices in a field study conducted in collaboration w ith law enforcem ent agencies in H illsborough C ounty, F lorida. M E T H O D S U rine specim ens w ere collected by police officers from persons placed u nder arrest for suspicion o f driving-under-the-influence (D U I) w ho consented to provide a specim en. T he Florida Im plied C onsent Law (C hapter , FS) provides the authority for requesting breath and urine specim ens from individuals arrested for suspicion o f D U I. B reath sam ples w ere collected by police officers and analyzed in accordance w ith the adm inistrative rules and -486-

3 law s o f F lorida by certified police breath-alcohol technicians on an evidentiary breath-testing device. T ypically the specim en donor had been pulled over for som e violation o f traffic code, had failed a roadside sobriety test, w as placed under arrest and brought to the C entral B reath T esting [CBT] facility at the H illsborough County Jail for toxicology testing and booking. D uring the tim e period from 16 D ecem ber 1995 to 17 M arch 1996 voluntary urine specim ens w ere collected from 305 D U I suspects. A pproxim ately 90% o f all specim ens w ere collected betw een the hours o f 10pm and 6am T hursdays, Fridays, and S aturday nights. U pon entering C B T, the arresting officer tim e-stam ps official docum ents to begin a 20-m inute direct observation period, w hich is required by law to precede the breath alcohol test. T he m ajority o f the officers preferred to w ait until after the breath test w as com pleted to request a urine specim en from the subject. T he officer put on latex gloves, provided the subject w ith a specim en cup, and requested that the subject proceed to the restroom and provide a urine specim en. T he o fficer ensured the lid w as properly secured, placed a coded label and evidence tape on the cup, and placed the cup in the refrigerator provided by the research group. Subjects generally w ere escorted to the bathroom facility w here they provided the specim en w ithout direct observation. Since all suspects are searched and patted dow n during the interview process the investigators believed that the possibility fo r specim en adulteration or substitution w as nil and direct observation w as unnecessary. A ccording to police records during the 12/15/95 to 3/17/96 tim e period the refusal rate to consent to breath testing w as 28.8%. T his rate is consistent w ith m onthly data going back several years. W hile a few individuals w ho refused to give a breath sam ple did agree to provide urine (n= 15), m ost individuals refusing to give breath also refused to provide urine. U nfortunately because o f a variety o f circum stances m any suspects w ere not asked to provide a urine specim en and it w as difficult to calculate a precise refusal rate. W hen the facility w as very busy, or w hen a suspect w as unruly or uncooperative, or too stoned to understand, o r too sick to follow directions a urine specim en w as not requested. W e estim ate that approxim ately 60% o f those suspects w ho w ere actually asked by the officers did consent to provide a specim en. F o u r on-site devices w ere selected for evaluation. C ost, ease o f handling, conduct o f the analysis, and the procedural aspects o f specim en collection and forensic chain-of-custody

4 docum entation w ere evaluated. A ccuracy and reliability o f the on-site test kits w ere evaluated by reanalysis o f specim ens in a forensic laboratory certified by the US D epartm ent o f H ealth and H um an S ervices and the data com pared w ith the on-site kit evaluations. T he details o f the on-site testkit evaluations are presented separately in a com panion paper E valuation o f the A ccuracy o f O n-site M ulti-analyte D rug T esting D evices in the D eterm ination o f the Prevalence o f Illicit D rugs in D rivers (B uchan, B.J., W alsh, J.M., and L eaverton, P.E.) R E SU L T S T he dem ographics for the 303 usable specim ens [2 specim ens had insufficient volum e to be tested on all kits] are as follow s: Subject P opulation Total N um ber = 303 Percent M ale Fem ales Subject Population by R ace Total N um ber = 303 Percent B reakout W hite Black H ispanic Asian 3 1 N ative Am erican 0 0 O ther

5 The follow ing is the age distribution o f the population studied. Actual N um ber Percent Breakout Subject P opulation by Age 0-19 years old O ne o f the specific aim s o f the project w as to determ ine the extent to w hich potentially im pairing drugs are found in drivers w ho fail to pass a roadside sobriety test. T he data indicate that overall 29% o f the specim ens collected (88/303) w ere confirm ed positive in the HHS certified laboratory for one or m ore illegal drugs. O f those individuals w ho w ere able to pass the breathalyzer test (i.e. BrA c <0.08) 41% w ere positive for one or m ore illegal d ru g s. Six individuals registered no alcohol (0.0% B ra c) and 4 o f these 6 (67% ) w ere positive for one o r m ore o f the drugs w e screened for. Tw o hundred sixty six subjects produced illegal BrA c concentrations w ith a m ean B ra c of (nearly tw ice the legal lim it) and 29.1% o f these legally drunk in d ivid u als (77/2661 were also confirm ed positive for one or m ore illegal d ru gs. T he m ean BrA c level o f the legally drunk/drugged individuals w as exactly that sam e as those w ho w ere only drinking [B A C = 0.154g% ]. BR A C Level # Individuals # Positive Drugs # N egative Drugs Percent Positive > % 0.01 to % % Refused Breath % T otals % O f the 288 subjects w ho consented to provide both breath and urine sam ples 30% (86/288) w ere under the influence o f illegal drugs. Since there w as a roughly 30% refusal rate for -489-

6 breath and an estim ated 40% refusal rate for urine w e can only assum e that these data represent a conservative estim ate o f the real scope o f the problem. DUI suspect toxicology Drunk - no drug 66% D ISC U SSIO N From the experience and know ledge gained from this field evaluation it is clear that routine drug testing is feasible and could be integrated into routine police operations. T hese data docum ent the fact that driving under the influence o f illegal drugs is a significant problem w hich has not been fully acknow ledged. W e suspect that a high percentage o f those individuals refusing to provide breath and urine specim ens w ould also have been identified as drug users and that these data present only a conservative estim ate o f the full scope o f the problem. T o prevent drug-related traffic accidents, law enforcem ent officials m ust be able to detect drivers under-the-influence o f drugs as they routinely do now w ith alcohol detection devices. T he availability o f technologically advanced on-site drug-testing devices w hich are capable o f providing im m ediate accurate and reliable results provides a unique opportunity to effectively apply this technology in traffic safety and the enforcem ent o f drugs and driving law s. W e firm ly believe that the routine availability of drug testing could be used as a pow erful prevention tool to detect and deter drugged driving behavior

7 R E F E R E N C E S A lcohol and O ther D rugs in T ransportation: R esearch N eeds for the N ext D ecade; T ransportation R esearch Board, N ational Research Council Pub. # 408, June 1993 B rookoff, D., C ook, C., W illiam s, C. and M ann, C. T esting R eckless D rivers for C ocaine and M arijuana. N ew E ngland Journal o f M edicine. 1994, 331: C rouch, D., B irky, M., G ust, S. R ollings, D., W alsh, J., M oulden, J., Q uinlan, K., and B eckel, R. T he Prevalence o f D rugs and A lcohol in fatally Injured D rivers, Journal o f F orensic Sciences. V ol. 38(6), pp , 1993 L indenbaum, G., C arrol, S., D askal, F., and K apusnick, R. Patterns o f A lcohol and D rug A buse in an U rban T rau m a C enter: T he increasing role o f cocaine abuse, Journal o f T rau m a. V 29( 12), , 1989 Soderstrom, C., T rifillis, A., Shankar, B., C lark, W., and C ow ley, R. M arijuana and A lcohol use am ong 1023 patients, A rchives of S urgery. Vol. 123, , W illette, R. and W alsh, J.M. (Editors), D rugs, D riving, and T raffic Safety, W orld H ealth O rganization. Pub. # 78, 1983, W orld H ealth O rganization, G eneva, Sw itzerland W illiam s, A.F., P eat, M.A., C rouch, D.J.,W ells, J.K., and Finkle, B.S. D rugs in fatally injured young m ale drivers, Public H ealth R eports. 100 (1), 19-25,

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