Chemical toxicological research is a laboratory diagnostic method that is aimed at the quantitative or qualitative recognition of foreign substances in the body. These are not only a variety of toxins, but also almost all compounds that enter the human body from the outside.
What is the analysis done for?
In pharmacology there is such a thing as the toxicology of drugs. For the most part, toxicological examinations are in a situation with the definition of psychotropic and narcotic substances, toxins, potent drugs, alcohol. Tests for various body fluids (often urine and blood), the presence and quantity of poisons are today considered to be a frequent component of the medical diagnostic procedure.
Chemical toxicological examination of urine
The simplest method to establish the reality of a person's involvement in the use of narcotic substances is urinalysis. The benefits of such a survey:
- ease of collection of urine - there is no need for the appearance of the person being checked in the laboratory;
- very good concentration of drugs;
- there is always a sufficient volume of the test product in case of the need for a secondary inspection.
A urine test reveals the use of drugs 3-6 days before it. Cannabinoids, for example, are in the urine, and after 3 weeks after administration they penetrate the patient's adipose tissue. But their release from the tissue is different in duration - this makes it possible to determine the consumption of narcotic substances within 20-22 days.
Urinalysis
Chemical toxicological research is carried out in two ways:
- Immunochromatographic, which is an express method and is performed right after urine collection. The result is already ready after 10-15 minutes, with it you can identify 14 types of drugs.
- Chemical-toxicological - detects all popular narcotic and psychotropic substances. Analysis takes 4 days.
Immunochromatographic method
This technique makes it possible to make a test to determine the result of taking such groups of drugs:
- cocaine;
- amphetamine and its formation (ecstasy, methamphetamine);
- opiates (codeine, heroin, morphine);
- barbiturates (Cyclobarbital, Barbamil, Phenobarbital);
- cannabinoids;
- alcohol in the urine (chemical-toxicological studies are also carried out for such a substance);
- opioids ("Phencyclidine", "Tramadol", "Methadone");
- benzodiazepines (Nitrazepam, Relanium, Diazepam, Seduxen, Phenazepam);
- cannabis drugs (hash, marijuana).
Feature of testing urine for drugs
The test liquid, being absorbed and moving through the adsorbing mechanism in the presence of an established substance or its metabolites in it, reacts with special antibodies, creating an antigen-antibody complex. The latter reacts with the antigen immobilized on the analysis strip with results from 1 to 5. However, the red mark on the strip does not appear if the saturation of the drug in the specimen does not exceed the limit level.
If the narcotic substance is absent, or its concentration is below the threshold limit, then the antigen present in the test zone of the line begins to interact with another antibody. In this place, a pink stripe is found. And a certificate of the results of chemical toxicological studies further confirms this. The detection of such a strip in the control part indicates the reliability of the survey and the diagnostic activity of its elements.
A positive result of the analysis leads to the appearance of only one pink line in the control zone, which indicates the presence of a narcotic substance. A negative outcome, on the contrary, leads to the appearance of two pink stripes in the test area, that is, indicates the absence of drugs in the test sample or confirms that its saturation is less than the limit level.
The order of analysis for narcotic substances
The testing event (for example, a chemical toxicological study for weapons) and the system for studying the results differ slightly depending on who the subject of the examination is and where it is carried out. Everything goes this way: urine is taken in a clean container of 50 ml, the test is immediately performed, and the result itself appears after 15-20 minutes. If the presence of narcotic substances is confirmed, then the analysis will be formalized in a protocol of the results of a study on narcotic substances in urine by the immunochromatic method.
Chemical toxic method
This drug screening method includes:
- Examination of urine for alcohol by gas chromatography.
- Enzyme-linked immunosorbent assay (IMA) of psychotropic and narcotic elements in urine.
- Urine drug test by chromatography mass spectrometry.
- Polarization fluorescence immunoassay (PFIA) of urine for any of the following types of drugs (amphetamines, benzodiazepines, Methadone, cocaine, Phencyclidine, cannabinoids, barbiturates, opiates). A certificate of a chemical toxicological study is issued for all these groups.
The principle of material selection
Selection is done in an environment that excludes the possibility of substitution or replacement of a biological object. Urine is collected by the test subject in plastic graduated or glass containers with a wide neck and a volume of not less than 30 and not more than 200 ml. The test person gives the liquid container to the laboratory assistant for analysis.
When urine is sent for chemical toxicological examinations for the presence of alcohol, its metabolites and surrogates, it is poured after collection into a dry sterile 10 ml container, closed with a rubber stopper and sealed.
In order to conduct a chemical-toxicological study for weapons for the presence of psychotropic, toxic and narcotic drugs, as well as alcohol and its substitutes, urine must be transported to the laboratory no later than two days from the moment of collection. The test liquid is stored in the refrigerator until dispatch. The collected urine with accompanying documents is delivered in a closed and sealed container in a cooler bag by courier.
Chemical toxicological research for security guards
In accordance with the innovations, departmental escort workers and individual security guards must undergo a medical examination every year , which includes a chemical toxicological analysis for the presence of drugs, psychotropic drugs and their metabolites in the body.
A Russian citizen is required to submit a medical report on the absence of narcotic substances in the body to acquire a license to buy weapons or extend the rights to it. This document is valid for exactly one year.
It should also be noted that a chemical-toxicological study for guards and an examination by a psychiatrist-narcologist for medical contraindications for carrying weapons are carried out in medical institutions at the place of residence and at the expense of citizens' income.
Rules for detecting the presence of drugs in the body during a medical examination
Current requirements include a plan for determining the presence of narcotic or psychotropic substances in the body when conducting a medical check for the state of intoxication of a patient who is driving a vehicle:
- Recognition of the presence of drugs or psychotropic substances in the human body is carried out solely on the basis of a referral to a chemical toxicological study issued by a doctor, which indicates the intoxication of the person driving the vehicle.
- The presence of narcotic drugs or psychotropic matter is determined in the laboratories of organizations that hold a license to carry out medical work with a list of related services.
- The results of chemical toxicological examinations when determining the presence of psychotropic substances or drugs are recorded in the certificate with the results of chemical toxicological analyzes (instructions and form are determined by the Ministry of Health and Social Development of the Russian Federation).
- A document confirming the chemical-toxicity study is attached to a copy of the medical examination certificate for the state of intoxication of the person driving the vehicle.
- The rules for the implementation of chemical toxicological testing, the timing of its conduct, as well as the reporting forms are determined by the Ministry of Health of Russia.
Who needs to do such research
The described procedure must be carried out:
- people who are outside the Russian Federation for the legal registration of migration documents;
- persons entering secondary and higher educational institutions, and students studying in military departments;
- children whose parents have reason to assume that they are taking drugs;
- employers who hire people in decreed professions;
- when performing a medical check for the use of drugs, alcohol, when establishing guilt in traffic accidents.
It remains to answer the last question: "Where to undergo a chemical toxicological study?" This procedure is carried out in specialized laboratories of intoxication therapy centers.