Chemical-toxicological research is a method of laboratory diagnostics, which is aimed at numerical or qualitative recognition of foreign substances in the body. These are not only various toxins, but also almost all compounds that enter the human body from the outside.
What the analysis is for
In pharmacology there is such a thing as the toxicology of drugs. For the most part, we are talking about toxicological examinations 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 amount of poisons are today considered a frequent part of the diagnostic and treatment procedure.
Chemical-toxicological study of urine
The easiest method to establish the reality of a person's involvement in taking drugs is a urine test. Advantages of such a survey:
- ease of urine collection - there is no need for the testee to appear in the laboratory;
- very gooddrug concentration;
- always a sufficient volume of test product in case a secondary examination is needed.
Urine test detects drug use 3-6 days before testing. Cannabinoids, for example, are found in the urine, and after 3 weeks after ingestion, they penetrate into the adipose tissue of the patient. But their release from the tissue differs in duration - this makes it possible to determine the consumption of narcotic substances within 20-22 days.
Urine diagnostics
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 ready after 10-15 minutes, with the help of 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 formations (ecstasy, methamphetamine);
- opiates (codeine, heroin, morphine);
- barbiturates ("Cyclobarbital", "Barbamil", "Phenobarbital");
- cannabinoids;
- alcohol in the urine (for such a substance, chemical and toxicological studies are also being carried out);
- opioids("Phencyclidine", "Tramadol", "Methadone");
- benzodiazepines ("Nitrazepam", "Relanium", "Diazepam", "Seduxen", "Phenazepam");
- drugs from cannabis (hashish, marijuana).
Feature of testing urine for drugs
The test liquid, being absorbed and moving through the adsorbing mechanism in the presence of the established substance or its metabolites, reacts with specific antibodies, creating an "antigen-antibody" combination. 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 there is no narcotic substance, or its concentration is below the threshold limit, then the antigen in the test zone of the line begins to interact with another antibody. In this place, a pink stripe is found. And the 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 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 indicates the presence of a narcotic substance. A negative outcome, on the contrary, leads to the appearance of two pink stripes in the zonetest, that is, indicates the absence of drugs in the test sample or confirms that its saturation is less than the limit level.
Procedure for drug testing
The testing activity (eg a chemical-toxicological test for a weapon) and the way the results are reviewed differ slightly depending on who is the subject of the test and where it is carried out. Everything goes like this: urine is taken into 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 issued by the protocol of the results of the study for narcotic substances in the urine by the immunochromatic method.
Chemical-toxic method
This type of drug screening includes:
- Study of urine for alcohol by gas-liquid chromatography.
- Enzymatic immunoassay (IMA) of psychotropic and narcotic elements in urine.
- Urine drug test by chromato-mass spectrometry.
- Polarization fluorescence immunoassay (PFIA) of urine for any of the following types of drugs (amphetamines, benzodiazepines, "Methadone", cocaine, "Phencyclidine", cannabinoids, barbiturates, opiates). For all these groups, a certificate of chemical-toxicological examination is issued.
Material selection principle
Selection is done in an environment that excludes the possibility of substitution or replacementbiological object. Urine is collected by the test subjects in a plastic graduated or glass container with a wide neck with a volume of at least 30 and not more than 200 ml. The person being tested gives the container with the liquid to the laboratory assistant for analysis.
When urine is sent for chemical and toxicological examinations for the presence of alcohol, its metabolites and surrogates, after sampling, it is poured into a dry sterile container with a volume of 10 ml, closed with a rubber stopper and clogged.
In order 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 must be transported to the laboratory no later than two days from the date of collection. The dough liquid is stored in the refrigerator until dispatch. Collected urine with accompanying documents is delivered in a closed and sealed container in a cooler bag by courier.
Chemical-toxicological testing for security guards
In accordance with the innovations, employees of departmental escorts and individual security guards must undergo a medical examination every year, which includes a chemical and toxicological analysis for the presence of drugs, psychotropic drugs and their metabolites in the body.
A citizen of Russia, in order to acquire a license to purchase weapons or extend the rights to it, must submit to the internal affairs body at the place of residence a medical certificate confirming the absence of narcotic substances in the body. Such a document is valid for exactly one year.
It should also be noted that chemical and toxicological examination for security guards and examination by a psychiatrist-narcologist for medical contraindications to 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 during a medical examination
The current requirements include a plan for determining the presence of narcotic or psychotropic substances in the body when performing a medical examination for the state of intoxication of a patient who drives 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 for a chemical-toxicological examination issued by a doctor, which indicates the intoxication of the person driving the transport.
- Determination of the presence of narcotic drugs or psychotropic matter is done in the laboratories of organizations that hold a license to carry out medical work with a list of relevant services.
- The results of chemical-toxicological examinations when establishing the presence of psychotropic substances or drugs are recorded in a certificate with the results of chemical-toxicological analyzes (instructions and form are determined by the Ministry of He alth and Social Development of the Russian Federation).
- A document confirming the chemotoxic study is attached toa copy of the act of medical examination 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 reporting forms are determined by the Ministry of He alth of Russia.
Who needs to conduct 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, higher educational institutions, and students studying at military departments;
- children whose parents have reason to believe that they are taking drugs;
- employers hiring people in decreed professions;
- when performing a medical check for drug use, alcohol, when establishing guilt in traffic accidents.
It remains to answer the last question: "Where to take a chemical-toxicological study?" This procedure is carried out in specialized laboratories of intoxication therapy centers.
