Chemico-toxicological examination of urine

Chemical-toxicological study is a method of laboratory diagnosis, which is aimed at the numerical or qualitative recognition of foreign substances in the body. It is not only a variety of toxins, but virtually all compounds that enter the human body from the outside.

What is the analysis for?

In pharmacology there is such a thing as toxicology of medications. For the most part, toxicological examinations are in the situation with the definition of psychotropic and narcotic substances, toxins, potent drugs, alcohol. Tests for various biological fluids of the body (often urine and blood), the presence and number of poisons are now considered to be a frequent component of the treatment and diagnostic procedure.

Chemico-toxicological examination of urine

The simplest method of establishing the reality of a person's involvement in the taking of narcotic substances is the analysis of urine. The advantages of such a survey:

• Ease of the collection of urine - there is no need for attendance checked in the laboratory;
• Very good concentration of drugs;
• Always sufficient volume of the investigated product in case of need of secondary inspection.

Urine examination detects the use of narcotic drugs for 3-6 days before it is carried out. Cannabinoids, for example, are in the urine, and after 3 weeks after ingestion they penetrate the adipose tissue of the patient. But their release from the fabric differs in duration - this makes it possible to determine the consumption of narcotic substances within 20-22 days.

Diagnosis by urine

The chemical-toxicological study is carried out in two ways:

1. Immunochromatographic, which is an express method and is performed right after the urine is collected. The result is already ready after 10-15 minutes, with the help of which it is possible to identify 14 varieties of drugs.
2. Chemical-toxicological - detects all the most popular narcotic and psychotropic substances. The analysis takes 4 days.

Immunochromatographic method

This technique makes it possible to make a test for determining the result of taking such groups of drugs:

• cocaine;
• Amphetamine and its formulations (ecstasy, methamphetamine);
• Opiates (codeine, heroin, morphine);
• Barbiturates ("Cyclobarbital", "Barbamil", "Phenobarbital");
• Cannabinoids;
• Alcohol in the urine (for such a substance, chemical-toxicological studies are also carried out);
• Opioids ("Fentziklidin", "Tramadol", "Methadone");
• Benzodiazepines ("Nitrazepam", "Relanium", "Diazepam", "Seduxen", "Phenazepam");
• Narcotic drugs from cannabis (hashish, marijuana).

The peculiarity of urine testing for drugs

The test fluid, absorbed and moving through the adsorption mechanism in the presence of the substance or its metabolites in it, reacts with specific antibodies, creating a set of "antigen-antibody". The latter reacts with the antigen immobilized on the analysis strip with results from 1 to 5. At the same time, 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 not present, or its concentration is below the threshold limit, then the antigen remaining in the test zone of the line begins to interact with another antibody. In this place, a pink strip is found. And a certificate of the results of chemical-toxicological studies in the future confirms this. The detection of such a strip in the control part indicates the reliability of the performance of the examination 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 makes it possible to know about the presence of a narcotic substance. Negative outcome, on the contrary, leads to the appearance of two pink stripes in the test zone, that is, indicates the absence of drugs in the test sample or confirms that its saturation is lower than the limit level.

Procedure for the analysis of narcotic substances

The testing event (for example, a chemical-toxicological study for weapons) and the system for studying the results vary slightly depending on who is the subject of the survey and where it is carried out. Everything goes this way: urine is taken into a clean container of 50 ml, the test is immediately produced, and the result appears after 15-20 minutes. If the presence of narcotic substances is confirmed, then the analysis will take the form of a protocol of the results of the study on drugs in the urine immunochromatically.

Chemical and toxic method

This method of drug screening includes:

1. Urine test for alcohol by gas-liquid chromatography.
2. Immunoenzyme analysis (IMA) of psychotropic and narcotic elements in the urine.
3. Drug test in urine by chromatography-mass spectrometry.
4. Polarization fluorescent immunoassay (PFIA) of urine on any of the given varieties of drugs (amphetamines, benzodiazepines, "Methadone", cocaine, "Fentziklidin", cannabinoids, barbiturates, opiates). All of these groups receive a certificate of a chemical-toxicological study.

Principle of material selection

Selection is done in an environment that excludes the possibility of substitution or replacement of a biological object. Collection of urine is made by the subject in a plastic graduated or glass with a wide neck container of not less than 30 and not more than 200 ml. The test gives a container of liquid to a laboratory technician for analysis.

When urine is sent for chemical-toxicological examinations for the presence of alcohol, its metabolites and surrogates, it is poured into a 10 ml dry sterile container, closed with a rubber stopper and clogged.

To carry out a chemical-toxicological study for weapons for the presence of psychotropic, toxic and narcotic drugs, as well as alcohol and its substitutes, urine should be transported to the laboratory no later than two days after the fence. Before dispatch, the test liquid is stored in the refrigerator. The collected urine with accompanying documents is delivered in a sealed and sealed container in a refrigerator bag by a courier.

Chemical-toxicological study for guards

In accordance with the innovations, departmental escort workers and individual 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 citizen of Russia to obtain a license to purchase weapons or to extend the rights to him must submit to the internal affairs body at the place of residence a medical report on the absence of narcotic substances in the body. Such a document is valid for exactly one year.

It should also be noted that a chemical-toxicological study for guards and examination by a psychiatrist-narcologist for medical contra-indications for carrying weapons are carried out in medical institutions at the place of residence and at the expense of citizens' incomes.

Rules for detecting the presence of drugs in the body when performing a medical examination

Current requirements include a plan for determining the presence of narcotic or psychotropic substances in the body when performing a medical check on the state of intoxication of the patient who drives the vehicle:

1. Recognition of the presence of drugs or psychotropic substances in the human body is performed 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 transport.
2. The presence of narcotic drugs or psychotropic matter is determined in the laboratories of organizations that hold a license to conduct medical work with the transfer of relevant services.
3. The results of chemical-toxicological examinations when establishing the presence of psychotropic substances or drugs are recorded in a certificate of the results of chemical-toxicological analyzes (the instruction and the form are determined by the Ministry of Health and Social Development of the Russian Federation).
4. The document confirming the chemical-toxic study is attached to the copy of the medical inspection certificate for the intoxication of the person administering the vehicle.
5. The rules for the implementation of chemical-toxicological testing, the timing of its conduct, as well as reporting forms are determined by the Ministry of Health of Russia.

Who is required to conduct such studies?

The described procedure should be carried out:

• People outside the Russian Federation for the legal registration of migration documents;
• People entering secondary, higher educational institutions, and students studying at military departments;
• Children whose parents have reason to admit that they are taking drugs;
• Employers recruiting people for jobs that have been decreed;
• When performing a medical check for the use of drugs, alcohol, in establishing the culpability of road accidents.

It remains to answer the last question: "Where to pass the chemical-toxicological study?" Such a procedure is carried out in specialized laboratories of intoxication therapy centers.