Drug testing is a process by which biological samples (such as urine, hair, blood or breath) are analyzed to determine if certain drugs or their metabolites are present. This can be done for a variety of reasons, including pre-employment screening, post-accident/incident investigation, and in the case of substance abuse treatment.
Tests used in the clinical setting include rapid qualitative urine immunoassays and confirmatory tests that may involve gas chromatography or mass spectrometry. Both methods of testing have a number of drawbacks, but they do have important clinical applications for the detection and monitoring of substance use.
The accuracy of a test depends on several factors, including the specific drugs tested, the amount of drug taken, the type and frequency of drug abuse, the time between drug intake and testing, and other variables that can affect the results of a test. Some of these factors, such as the time between drug consumption and testing, can be difficult to control, making a positive or negative test result highly unpredictable.
There are a number of drug tests available, but the most common ones are urine, blood, and hair. Urine tests are cheap and easy to administer. They can detect a wide range of prescription and illegal drugs.
Blood tests can be invasive and may require the administration of a needle, but they are less likely to be tampered with than other forms of drug testing. They are also faster and can provide a more accurate assessment of recent drug use.
Saliva testing is an inexpensive and non-invasive form of drug testing that can be performed in the clinical setting. Saliva is a relatively clean liquid, and it can be tested for many types of drugs.
Some of the most common drugs tested in saliva are amphetamines, cocaine, marijuana and THC, opiates, benzodiazepines, methamphetamines, and PCP. The length of time that these drugs are detected in a saliva sample is short, typically one to three days after drug use.
Hair tests can be conducted over a longer period of time, but it is often less accurate than urine or blood. It can detect cocaine, opiates, amphetamines and methamphetamines, ecstasy, phencyclidine (PCP), and alcohol.
The most common reason for testing is to ensure that an employee is not impaired by a drug. This is particularly important in safety-sensitive jobs such as train engineers, airline pilots, and truck drivers. In these cases, alertness and sobriety are essential for avoiding accidents and injuries.
In addition, there is a growing body of evidence that demonstrates that the workplace can be a safe and productive environment when employees are sober and drug-free. This is a major benefit of drug testing, as it can prevent the risk of serious injuries and loss of life.