Alcohol and Drug Testing

Types of alcohol and drug testing

Major league baseball players, operators of heavy machinery, school children and even those applying for employment have one thing in common - alcohol and drug testing has become routine in each of their situations.

Tests that reveal alcohol and drugs in the human body work by detecting current and residual substance levels. Tests can prove a history of drug use by recording the presence of drug metabolites, or the residue drugs leave in the body after they have worked through the system.

So what are the most common types of testing?

Blood test . A blood sample is the most reliable way to prove the presence of alcohol and drugs in the body. Invasive and costly, the procedure is rarely used.

A breath alcohol test . Measures the immediate amount of alcohol in the subject's blood. As the subject blows into the test device, or Breathalyzer, the machine detects how much alcohol is expelled the breath. The result is known as the Blood Alcohol Concentration (BAC). States set their own BAC limits, with most relying on 0.08 as the legal limit. Commonly used to determine the intoxication level of a drunk driver, the test cannot identify drug use.

Hair analysis . The hair shaft retains residue from any substances smoked, ingested and/or injected into your body in the past. Thus hair provides a reliable record of drug use, especially in chronic drug cases. Hair analysis proves use as far back as 90 days, but cannot measure activity within the past 1-7 days, or measure alcohol use.

Oral fluids . A simple swab of saliva confirms drug use and impairment within the last 24 hours. Able to detect alcohol and drugs, the process is simple and non-invasive, and there is a low risk of tampering.

Sweat patch test . Perspiration also determines the presence of drugs in your system. A large adhesive bandage is fixed to the skin and left for 1-7 days, where it will absorb sweat and record any drug use during that time. Common in the prison system to regulate parolees, the sweat patch test is rare in schools or the workplace.

Testing a urine sample . The most popular method. A sample of urine is the best way to prove the presence of drugs or drug residue in the body. A urine sample will pick up any drug use within the last 1-5 days, and is considered reliable in court.

New Zealand Drug Tests and Testing