Drug test
Major applications of drug testing include detection of the presence of performance enhancing steroids in sport, employers and parole/probation officers screening for drugs prohibited by law (such as cocaine, methamphetamine, and heroin) and police officers testing for the presence and concentration of alcohol (ethanol) in the blood commonly referred to as BAC (blood alcohol content).
[1] The detection windows depend upon multiple factors: drug class, amount and frequency of use, metabolic rate, body mass, age, overall health, and urine pH.
Due to the very low levels of substances in the breath air, liquid chromatography—mass spectrometry has to be used to analyze the sample according to a recent publication wherein 12 analytes were investigated.
Rapid oral fluid products are not approved for use in workplace drug testing programs and are not FDA cleared.
A drug, if present in the urine specimen below its cut-off concentration, will not saturate the binding sites of its specific antibody.
The patient or employee's urine is collected at a remote location in a specially designed secure cup, sealed with tamper-resistant tape, and sent to a testing laboratory to be screened for drugs (typically the Substance Abuse and Mental Health Services Administration 5 panel).
Others are intended to catch substances added to the urine to alter the test result, such as, oxidants (including bleach),[25] nitrites,[26] and gluteraldehyde.
If the result of the screen is negative, the MRO informs the employer that the employee has no detectable drug in the urine, typically within 24 hours.
However, if the test result of the immunoassay and GC-MS are non-negative and show a concentration level of parent drug or metabolite above the established limit, the MRO contacts the employee to determine if there is any legitimate reason—such as a medical treatment or prescription.
[28] On-site instant drug testing is a more cost-efficient method of effectively detecting substance use amongst employees, as well as in rehabilitation programs to monitor patient progress.
[31] More modernly used instruments are the infrared light-absorption devices and fuel cell detectors, these two testers are microprocessor controlled meaning the operator only has to press the start button.
To get accurate readings on a breath-testing device the individual must blow for approximately 6 seconds and need to contain roughly 1.1 to 1.5 liters of breath.
The agency did not comment on the test validity, but rather stated, that it lacks the statutory authority to adopt new analytical methods.
On the other hand, the sebaceous glands produce FAEEs in the scalp and these migrate together with the sebum along the hair shaft (Auwärter et al., 2001, Pragst et al., 2004).
The test involves mixing the suspicious material with a chemical in order to trigger a color change to indicate if a drug is present.
The tests are used for general screening purposes, offering a generic result for the presence of a wide range of drugs, including Heroin, Cocaine, Methamphetamine, Amphetamine, Ecstasy/MDMA, Methadone, Ketamine, PCP, PMA, DMT, MDPV, and may detect rapidly evolving synthetic designer drugs.
Duquenois-Levine reagent is a series of chemical solutions that turn to the color of purple when the vegetation of marijuana is added.
[39] In recent years, the use of presumptive test kits in the criminal justice system has come under great scrutiny due to the lack to forensic studies, questioned reliability, rendering of false positives with legal substances, and wrongful arrests.
[46] These are used by child protective services, parole departments, and other government institutions concerned with drug use over long periods, when urine testing is not practical.
Various panels are used for screening urine samples for common substances, e.g. triage 8 that detects amphetamines, benzodiazepines, cocaine, methadone, opiates, cannabis, barbiturates and tricyclic antidepressants.
Employers such as the commercial driving and airline industry may conduct random drug tests on employees with the goal of deterring use to improve safety.
The confirmation test in most laboratories (and all SAMHSA certified labs) is performed using mass spectrometry, and is precise but expensive.
Most laboratories save positive samples for some period of months or years in the event of a disputed result or lawsuit.
In a practical test, hair sample is usually washed with a low polarity solvent (such as dichloromethane) to remove surface contaminations.
[75] A study in 2004 by the Independent Inquiry into Drug Testing at Work found that attempts by employers to force employees to take drug tests could potentially be challenged as a violation of privacy under the Human Rights Act 1998 and Article 8 of the European Convention of Human Rights.
[78] These decisions were then incorporated into the White House Drug Control Strategy directive issued by President George H.W.
It has been argued that one of the problems with such testing is that there is often not enough time between the arrest and the bail decision to confirm positive results using GC/MS technology.
It has also been argued that such testing potentially implicates the Fifth Amendment privilege against self-incrimination, the right to due process (including the prohibition against gathering evidence in a manner that shocks the conscience or constitutes outrageous government conduct), and the prohibition against unreasonable searches and seizures contained in the Fourth Amendment.
PCBUs are encouraged to establish a policy and procedure, in consultation with workers, to constructively manage alcohol and other drug related hazards in their workplace.
[92] In the United States federal criminal system, refusing to take a drug test triggers an automatic revocation of probation or supervised release.
