GLOSSARY OF TOXICOLOGY TERMS
Toxicology - Toxicology is often defined as “the study of the nature and mechanism of toxic effects of substances on living organisms and other biologic systems.” In simpler terms, “Toxicology is the study of the adverse effects of chemical and physical agents on living organisms.”
Adulterated Specimen - This term refers to a sample of body fluid or tissue that has been tampered with in some way.
Active Metabolite - An active metabolite results when a drug is metabolized by the body into a modified form which continues to produce effects in the body. Usually these effects are similar to those of the parent drug but weaker, although they can still be significant (e.g. 11-hydroxy-THC, morphine-6-glucuronide).
Accession Number - A number used to identify a sample as it passes through the laboratory process in order to keep track of where it goes through the system.
Affidavit - A form that must be signed by the collector to correct a problem on the original Chain of Custody form. For example, if the date was missing or incorrect.
Analyte – A substance whose chemical constituents are being identified and measured.
Antigen - A substance that when introduced into the body stimulates the production of an antibody. Antigens include toxins, bacteria, foreign blood cells, and the cells of transplanted organs.
Blind Specimen - A specimen that is taken and sent to a lab with the intention of acting as a quality control for that lab. This type of specimen is shipped with a fake identifier to hide its purpose.
Breath Alcohol Concentration (or Content) - The alcohol contained in a volume of breath expressed in terms of grams of alcohol per liters of breath.
Cancelled Test - A drug or alcohol test that has an identified problem that cannot be, or has not been corrected, which requires it to be cancelled. A cancelled test is neither a positive nor a negative test.
Cathinone (also known as benzoylethanamine, or β-keto-amphetamine): A monoamine alkaloid found in the shrub Catha edulis (khat) and is chemically similar to ephedrine, cathine, methcathinone and other amphetamines. Other phenethylamines that share this structure include the stimulants methcathinone, MDPV, mephedrone and the antidepressant bupropion among others.
Chain of Custody - The record kept of how the specimen was handled and by who over the course of the drug testing process, from the time it leaves the person being tested to the point at which it is destroyed after drug testing is complete.
CLIA - Clinical Laboratory Improvement Amendments, which are federal regulatory standards that apply to all clinical laboratory testing performed on humans in the United States except clinical trials and basic research. They were passed by congress in 1988. The CLIA Program sets standards and issues certificates for clinical laboratory testing, defined by the CLIA as any facility which performs laboratory testing on specimens derived from humans for the purpose of providing information (1) for the diagnosis, prevention, or treatment of disease or impairment, and (2) for the assessment of health. An objective of the CLIA is to ensure the accuracy, reliability and timeliness of test results regardless of where the test was performed.
Clinic - A medical facility that can be used as a collection site.
Clinical Toxicology - Clinical toxicology is the study of how drugs and chemicals affect the body. The findings from clinical toxicology are used to inform clinical decisions. Included in the scope of clinical toxicology is the determination of factors that usually lead to drug overdoses and poisoning. These factors include a patient's incorrectly using prescribed drugs, overprescribing of drugs, and inattention to drug warnings. See also “Forensic Toxicology”
CLIA - waived - Products, including many health and drug testing products, that pass certain criteria that have been proven to be easy to use and highly accurate. Some lab tests performed with standardized equipment are very easy to perform and when performed properly, have very little chance for error. When it can be proven using CLIA waived criteria that inaccuracy is almost impossible for these tests, the tests can be CLIA waived. CLIA waived medical products and equipment are cleared through the Federal Drug Administration and are available for purchase and use by consumers.
Collection Container - A container into which a person urinates or some other bodily fluid is collected to provide a specimen for a drug test.
Collection Site - A place selected by the tester where people to be tested present themselves for the purpose of providing a specimen for a drug test.
Collector - A person who instructs and assists test subjects at a collection site, who receives and makes an initial inspection of the specimen provided by those subjects, and who initiates and completes the Chain of Custody Form.
Comorbidity - The term “comorbidity” describes two or more disorders or illnesses occurring in the same person. They can occur at the same time or one after the other. Comorbidity can also refer to the relationship between drug use disorders and other mental illnesses, including why these disorders can co-occur, how common they are, and how they are diagnosed and treated.
Confirmation Test - A test that is used to confirm the presence of a specific drug or metabolite after the initial immunoassay test has been done. The confirmation testing method is usually liquid chromatograph/mass spectrometry (LC/MS).
Continuing Education - Training for medical review officers and substance abuse professionals who are currently working in the field, designed to keep them up-to-date on changes and developments in the DOT drug and alcohol testing program.
Control Line - On an instant drug test, this is the line that should appear in the control section of the test regardless of whether it is a positive or negative result. If no control line appears, the test is invalid.
Creatinine - A product created by the breakdown of creatine phosphate in muscle, usually produced at a constant rate by the body. Testers can determine if a sample has been diluted by testing the creatinine levels of the sample.
Cutoff Level - In drug testing, this is the minimum amount of a drug metabolite that must be present in a sample to determine if it is a negative or positive test. Cutoff levels are established to avoid false positive test results due to incidental exposure to a substance. For example, a person who has breathed in second hand marijuana smoke may have traces of marijuana show up in their urine or saliva sample but this will be below the minimum amount needed for a positive test, meaning the test will be negative.
CYP3A4 Enzyme – The CYP3A4 enzyme metabolizes more than 50% of all drugs; consequently, opioids metabolized by this enzyme have a high risk of drug-drug interactions.
Designer Drug - A synthetic version of a controlled substance (such as heroin) that is produced with a slightly altered molecular structure to avoid having it classified as an illicit drug.
Diluted Specimen - A diluted specimen is a specimen that has been diluted to the point where the drug traces or metabolites are also diluted, making them appear less concentrated. This is either the result of the donor drinking large amounts of a liquid before the urine collection or the donor adding water to the specimen after collection. Dilution can be detected by measuring the creatinine level and specific gravity of a sample.
Drug Metabolites - A chemical that is released during the ingesting process when the body metabolizes a drug. These chemicals are what drug screens check for. Particular substances produce particular metabolites.
Ecstasy - Also known as MDMA, it is a popular recreational drug that is a refined and processed form of amphetamine with a chemical structure closely resembling methamphetamine.
Endogenous Agonists - In pharmacology, an endogenous agonist for a particular receptor is a compound naturally produced by the body which binds to and activates that receptor. For example, the endogenous agonist for serotonin receptors is serotonin, and the endogenous agonist for dopamine receptors is dopamine.
EtG - Ethyl Glucuronide. In terms of alcohol testing, EtG is a direct, non-volatile, water soluble, metabolite of ethanol. It’s a highly sensitive and specific bio-marker and can be detected anywhere from four to five days after alcohol consumption as opposed to eight to 12 hours when testing for ethanol.
EtS - Ethyl sulfate. It is tested in conjunction with EtG for confirmation purposes. EtS is a direct, bio-marker of alcohol ingestion that is not susceptible to degradation by bacteria hydrolysis.
Forensic Toxicology - Forensic toxicology is the use of toxicology and other disciplines such as analytical chemistry, pharmacology and clinical chemistry to aid medical or legal investigation of death, poisoning, and drug use. See also, “Clinical Toxicology”
GC/MS - Gas chromatography-mass spectrometry. A testing method that combines the features of gas-liquid chromatography and mass spectrometry to identify different substances within a test sample. In drug testing terms, this is often used as the confirmation test on a sample that is found, by an immunoassay test, to contain traces of drugs.
Glucuronidation - The glucuronidation pathway often accounts for a major portion of drug metabolites that are found excreted in urine. Glucuronides are formed by a family of soluble liver microsomal enzymes, the uridine diphosphate(UDP)-glucuronosyltransferases (UGTs).
Half Life - This is the period of time required for the concentration or amount of drug in the body to be reduced by one-half. We usually consider the half-life of a drug in relation to the amount of the drug in plasma. A drug's plasma half-life depends on how quickly the drug is eliminated from the plasma.
HHS - The Department of Health and Human Services or anyone designated by the Secretary, Department of Health and Human Services to represent that department.
Immunoassay - A biochemical test that measures the presence or concentration of a macromolecule in a solution through the use of an antibody or immunoglobulin. In regards to drug testing, it is the first test done to detect whether there are any traces of a drug in a person’s system. More stringent follow-up testing is done if an immunoassay test gives a positive result. All instant drug tests are immunoassay tests.
Initial Drug Screen - An immunoassay test (EIA) that is the first test performed during a drug screening process to determine if there are any drug traces or metabolites present. If traces of drugs or metabolites are present, a confirmation test is performed.
Initial Validity Test - The first test used to determine if a specimen is adulterated, diluted, or substituted.
Instant test kit - An immunoassay test that can be purchased commercially by anyone for the purpose of detecting the presence of drugs in a person’s system. These tests can be performed anywhere that a sample can be obtained and the results are available instantly. The results of these tests may not hold up in a legal situation.
Invalid Drug Test - This is a drug test that has been tampered with and therefore invalidated for drug testing.
Laboratory - Any U.S. laboratory certified by the Department of Health and Human Services (HHS) under the National Laboratory Certification Program that meets the minimum standards of Subpart C of the HHS Mandatory Guidelines for Federal Workplace Drug Testing Programs; or, in the case of foreign laboratories, a laboratory approved for participation by the Department of Transportation under this part.
LC/MS - Liquid Chromatography - Mass Spectrometry is a testing method that combines the features of liquid chromatography, mass spectrometry to identify different substances within a test sample. In drug testing terms, this is used as the confirmation test on a sample that is found, by an immunoassay test, to contain traces of drugs.
LC/MS/MS - Liquid Chromatography - Mass Spectrometry and Liquid Chromatography - Tandem Mass Spectrometry is a testing method that combines the features of liquid chromatography, mass spectrometry and tandem mass spectrometry to identify different substances within a test sample. In drug testing terms, this is used as the confirmation test on a sample that is found, by an immunoassay test, to contain traces of drugs.
Metabolism - Metabolism refers to the process of biotransformation by which drugs are broken down so that they can be eliminated by the body. Some drugs perform their functions and then are excreted from the body intact, but many require metabolism to enable them to reach their target site in an appropriate amount of time, remain there an adequate time, and then be eliminated from the body.
Metabolite - A compound produced from the chemical changes of a drug in the body.
MRO - Medical Review Officer, a licensed physician in charge of receiving and then reviewing lab results made from an organizations’ drug testing program. The MRO is also in charge of evaluating those results for possible medical causes.
Negative Result - A result that indicates that the specimen did not exceed certain levels of drug metabolites.
NIDA - The National Institute on Drug Abuse is a United States federal-government research institute whose mission is to "lead the Nation in bringing the power of science to bear on drug abuse and addiction."
Non-negative specimen - A urine specimen that is reported as adulterated, substituted, positive for drugs, or invalid.
Normal Result - A negative laboratory test.
Office of Drug and Alcohol Policy and Compliance - The office in the Office of the Secretary in the Department of Transportation that is responsible for coordinating drug and alcohol testing program matters within the Department and providing information concerning the implementation of these matters.
Opiate - A class of drugs derived from the opium poppy plant, Papaver somniferum. This includes both illicit drugs (heroin) and prescription drugs (morphine).
Parent Drug – A drug prior to being metabolized.
PCP - Phencyclidine, often referred to as "angel dust," was developed in the 1950s as an intravenous surgical anesthetic. As an illicit drug, it can be smoked, snorted or injected. Once quite popular, it is now relatively uncommon.
Pharmacology – Pharmacology is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function.
Pharmacokinetics – Pharmacokinetics, sometimes described as what the body does to a drug, refers to the movement of drug into, through, and out of the body—the time course of its absorption, bioavailability, distribution, metabolism, and excretion.
Point of Contact (POC) Test - A Point of Contact/Care test, also known as an instant drug test, is a device that is capable of performing an immunoassay test on a sample and provides instant results within a few seconds or minutes after the sample is collected. If the results are positive, the sample should be sent to a laboratory for confirmation testing.
Positive Test Result - A drug test that has been confirmed as positive by the laboratory. An immunoassay test can also yield a positive test result for a specimen but the specimen should be sent to a laboratory for confirmation testing. Only when a sample has been confirmed positive can it truly be referred to as a positive test result.
Prodrug - A prodrug is a medication or compound that, after administration, is metabolized (i.e., converted within the body) into a pharmacologically active drug. Inactive prodrugs are pharmacologically inactive medications that are metabolized into an active form within the body.
SAMHSA - Stands for Substance Abuse and Mental Health Services Administration. SAMHSA is the governing federal agency that regulates all approved drug testing laboratories and all standards in drug testing.
Security-Sensitive Position - A position in which the normal or periodic job responsibilities of the employee entail, at some point and to some degree, access to cash, securities, bonds, or other negotiable instruments, and/or precious and/or valuable commodities; involve the use of, or access to, firearms and/or other weapons and/or armaments; involve protection of property, valuables, and/or individuals; relate to matters of national security, military, or law enforcement; and/or entail access to assets and/or information vital to, sensitive for, and/or with high proprietary interest to a company [and for whom the illicit use of drugs and/or misuse of alcohol by the employee in that position could compromise the interests of the company and/or any individual or entity affiliated to, or in contact with, the company].
Shipping Container - A container that is used for transporting and protecting specimen bottles and associated documents from the collection site to the laboratory.
Specific Gravity - The ratio of the density of a substance (usually urine when talking about drug testing) to the density (mass of the same unit volume) of a reference substance (usually water). The normal range of specific gravity for urine compared to water is 1.010 - 1.025
Specimen Container - The container that, after being sealed and labeled according to applicable procedures, is used to hold the specimen during transportation to the laboratory.
Split Specimen - A split specimen refers to a urine specimen that is divided to ensure the integrity of the sample’s results. One portion of the sample is stored for later evaluation and the other is tested for drug use. If that specimen is returned as a positive test then the other portion can be tested if the person being tested or the organization that asked for the drug test have requested it in order to ensure the positive result is accurate.
Substance Abuse Professional - A person who evaluates employees who have violated a Department of Transportation drug and alcohol regulation and makes recommendations concerning education, treatment, follow-up testing, and aftercare.
Substituted Specimen - A specimen that did not come from the person who was supposed to provide the specimen. Usually pertaining to urine tests, the specimen might be another person’s urine or the urine of an animal or some other substance altogether.
Sympathomimetic - Sympathomimetic drugs (also known as adrenergic drugs and adrenergic amines) are stimulant compounds which mimic the effects of endogenous agonists of the sympathetic nervous system.
Temperature Strip - A strip that is used to determine whether or not the urine is in the 90-100 Degree Fahrenheit (32-38 Degree Celsius) range. This helps to ensure that tampering has not occurred.
THC - The principal psychoactive element of the cannabis (marijuana) plant.
WHO - World Health Organization. A specialized agency of the United Nations (UN) that is concerned with international public health.
Verified laboratory test - A laboratory test result that has been verified by the MRO.