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Compounds trapped in hair during growth collect and remain in the mature hair strand. Defined lengths of the hair strand can be analyzed to provide information on ingestion of a substance during the window of time corresponding to the growth period of the segment of hair analyzed. Both screening (immunoassay) and confirmation (liquid chromatography-tandem mass spectrometry, gas chromatography-mass spectrometry, gass chromatography-tandem mass spectrometry) methods for drugs in hair require methods of liquefaction and/or extraction of the solid hair fiber. Extensive washing of hair samples to remove external contamination and/or drugs from sweat prior to analysis is integral to a meaningful hair result, particularly to distinguish use from contamination and to utilize the hair’s ability to reflect dose. Some results of drugs-of-abuse analysis in washed hair of proven drug users ranged (in ng/10 mg hair) from the cut-offs to 2270 (cocaine), 559 (morphine), 79 (methamphetamine), and 150 (phencyclidine). The metabolite of cannabis use, carboxy-tetrahydrocannabinol, was present in users’ hair samples in amounts up to 76 pg/10 mg hair. Hair analysis for drugs of abuse is most widely used for pre-employment and workplace testing, but has also shown utility in criminal justice settings, for diagnostic and monitoring purposes in rehabilitation programs, in determining prenatal drug exposure, and other arenas.

New federal regulations proposed by the Department of Health and Human Services for drug testing of federal employees includes the addition of alternative specimens as well as the addition of alternative technologies for screening samples at the point of collection. Alternative technologies called point-of-collection tests (POCT) may use urine or oral fluids, and are either visually read or instrumented. eScreen® (eScreen, Inc.) is an instrumented urine POCT with an integrated SVT, adulteration assay, Web-based information management system, and paperless chain of custody form. eScreen’s instrumented system eliminates many potential areas of concern when testing samples at the point of collection. Safeguards that are present in a laboratory-based drug-testing environment are duplicated in eScreen’s decentralized point-of-collection drug-testing model. The key to eScreen’s robust point-of-collection model lies in the use of an extensive installed base of Internet-enabled eReaders and Web tools.

Persons abusing drugs attempt to adulterate urine specimens in order to beat drug testing. Dilution of urine in vivo by consuming excess fluid and various detoxifying agents available through the Internet is a common practice. Household chemicals such as bleach, acid, table salt, laundry detergent, toilet-bowl cleaner, vinegar, lemon juice, and Visine® (Pfizer) eye drops are also used for adulterating urine specimens. Most of these adulterants except Visine eye drops can be detected by routine specimen integrity tests (creatinine, pH, temperature, and specific gravity). However, certain adulterants, such as Klear™, Whizzies, Urine Luck™, and Stealth™, cannot be detected by using routine specimen integrity testing. These adulterants can successfully mask drug testing if the concentrations of certain abused drugs are moderate. Several spot tests have been described in the literature to detect the presence of such adulterants in urine. More recently, urine dipsticks are commercially available (AdultaCheck® 4 [Sciteck], Adulta-Check 6, Intect® 7 [Branan Medical Corporation]) for detecting the presence of such adulterants along with creatinine, pH, and specific gravity. Hair and saliva testing for abused drugs are gaining popularity because such specimens are collected directly from a person. Moreover, abused drugs can be detected for a longer time in hair. Recently, certain hair shampoo and saliva cleaning products have become available to beat drug testing involving hair or saliva specimens.

The use of commercial adulterants with the aim of defeating urine drug tests has become a growing problem for the drug-testing industry. Such products are easily available and act by substitution, dilution, and chemical adulteration. Regulatory guidelines to detect the presence of adulteration have been established. Several on-site adulteration test products are available. One of the widely used devices is Intect® 7 (Branan Medical Corporation), which is a dipstick covered with seven dry reagent pads that tests for creatinine, specific gravity, pH, nitrite, glutaraldehyde, bleach, and pyridinium chlorochromate. Intect 7 has been shown to detect all currently available commercial adulterants. For two oxidizing adulterants that appear to dissipate within a short period of time, Intect 7 was shown to be useful in detecting their presence on site.

Since the development of specialized drug courts in 1989, the drug court movement in the United States has swept through the criminal justice system, revolutionizing the way many court systems process drug, domestic violence, driving under the influence (DUI)/driving while intoxicated (DWI), juvenile, re-entry, and mental health cases. The movement has grown from one experimental court in Miami, Florida, to more than 1000 specialty courts in operation and another 500 in some stage of planning. The federal government, through the Bureau of Justice Assistance, provided more than $45 million in direct funding for drug courts in the United States during 2003. The Office of Justice Programs initial funding proposal for drug courts during fiscal year 2004 was $68 million.

Why did they do this? Because drug courts work. Through the use of intensive therapy programs, court management of client participation, drug testing, and other measurable standards, drug courts provide an objective standard for success within a therapeutic system heretofore characterized by subjectivity and ambiguous outcome measures.

Testing for drugs of abuse in Europe generally follows many of the trends that have been observed in the United States in recent times. However, adoption of drug testing in Europe as a whole is still considered to be around 10 yr behind that of the United States. Noticeably, there are vast differences within the individual countries in relation to end-users and legislation. In the health care arena, hospitals and treatment clinics are among the largest consumers of drug-testing kits. In the non-health care sector, criminal justice services and the workplace represent the high-volume end-users. At present, urine continues to be the most popular screening test matrix across Europe, with blood the preferred specimen for judicial and forensic confirmatory applications. Although more recently introduced matrices such as oral fluid and saliva have yet to gain widespread acceptance, they are expected to play an increasingly important role in the future.

The 21-mo Roadside Testing Assessment (ROSITA) project started in January 1999 and included a literature survey of drugs and medicines that have detrimental impacts on road users’ performance, an inventory of the available roadside drug-testing equipment for urine, oral fluid, and sweat, an evaluation of the operational, user, and legal requirements for roadside testing equipment in the different European Union countries, and an extensive evaluation of several devices in eight countries. On-site immunoassays were used for the detection of drugs in urine, oral fluid, and/or sweat in 2968 subjects. Police officers liked having the tools to detect drivers under the influence of drugs, and they were very creative in finding solutions to the practical and operational problems they encountered. On-site drug testing gave the police confidence, and saved time and money. Police officers had no major objections to collecting specimens of body fluids. In the majority of the participating countries, oral fluid was the preferred specimen. Some on-site urine tests (Rapid Drug Screen® [American Bio Medica], Syva® RapidTest− [Dade Behring], Dipro Drugscreen 5 [Dipro Diagnostics], Triage [Biosite Diagnostics]) yielded good results (accuracy >95%, sensitivity and specificity >90% compared with reference methods), but none had good results for all assays.

The sampling of oral-fluid or sweat specimens was well accepted by drivers. The on-site tests evaluated—Drugwipe® (Securetec Detektions-Systeme AG), Cozart Rapiscan (Cozart Bioscience Ltd.), and ORALscreen™ (Avitar Inc.)—were not sufficiently reliable (accuracy between 50 and 81% in comparison with blood results). Progress is needed for sampling, duration of the test, sample volume, and reliability. From 2003 to 2005, the ROSITA-II project will evaluate the newer on-site oral-fluid devices in six European countries and five US states.

For the drug-testing industry, this is a time of new technologies and changes. There are various forms of lateral-flow devices making drug testing easier and providing results in matters of minutes. Test matrices other than urine are being investigated in which windows of detection can be narrowed to a few hours for detection of driving under the influence or be extended to several months to provide a long-term history of drug use. Moreover, information on drug testing is now widely available on the Internet, so that many more nonscientists are educated about drug testing. In this final chapter, we attempt to provide our personal thoughts on the industrial and scientific trends.