What comes into your mind when you hear the term Toxicology? The words "toxic" and "poison" would more or less come right off the top of your head and perhaps you already have an idea of what toxicology is. Toxicology is the study of poisons. It may also be defined as the study of substances introduced exogenously into the body.
Toxicology is known to have 5 divisions, which are Drug Abuse Screening, Emergency Toxicology, Therapeutic Drug Monitoring (TDM), Industrial Toxicology, and Forensic Toxicology. Drug abuse screening test is used to find out whether an individual needs a professional help with drug abuse problem. Emergency toxicology is concerned with the adverse health effects of chemicals in cases of emergency (eg: salicylate poisoning in children). Therapeutic drug monitoring, on the other hand, is used to determine the concentration and dosage of drug that can cure and be beneficial to the patient since drug dosage is individualized and depends upon different factors like metabolism of the person, age, weight, etc. TDM is also used to determine whether the concentration of the drug is therapeutic (cures the patient), subtherapeutic, or toxic (kills the patient). Industrial toxicology deals with the factories that produce drugs, pesticides, and other products. It is concerned with the potential harmful and toxic effects of materials, products, and wastes on health and environment. And lastly, forensic toxicology is the science that deals with medicolegal aspects of drug testing.
The four major disciplines within toxicology are the following:
This study explains the cellular and biochemical effects of toxins. It gives a basis for rational therapy design and the improvement and development of tests to evaluate the degree of exposure of an individual who has been poisoned.
It deals with risk assessment or prediction of the level of exposure that will cause harm in humans through animal experiments.
This study focuses on medicolegal consequences of toxin exposure. It creates and confirms the analytic performance of the methods used to make evidence in legal situations, including the cause of death.
This study deals with the interrelationships between toxin exposure and disease states. It doesn't only focus on diagnostic testing but also therapeutic intervention.
There are two basic types of techniques involved in detecting the presence and/or the level of particular drugs, whether they are drugs of abuse or therapeutic drugs. These are immunochemical and chromatographic. Most drugs for which monitoring is standard can be assayed using homogeneous immunologic techniques (homogeneous immunoassay).
Homogeneous immunoassays are allow rapid and stat analyses of blood and urine constituents wherein there is no requirement for a phase separation, which is traditionally used to separate bound from free ligand. Chromatographic techniques, on the other hand, are used to qualitatively detect drugs of abuse and toxins and seldom used to detect levels of therapeutic drugs.
It is important to know the adverse effects of chemicals in the body so as to be aware how to detect and treat poisoning, which can cause life-threatening illness. If detected, the effects of poisons can often be reversed. Testing for the presence of drugs of abuse/or poisons in patients is now set to be done in emergency rooms and in employment screening.
References:
McPherson, R., Pincus, M., Henry's Clinical Diagnosis and Management by Laboratory Methods, 22nd Edition
Bishop, M., Fody, E., Schoeff, L., Clinical Chemistry Techniques, Principles, Correlations, 6th Edition
