Contemporary Toxicological Analysis

Screening methods are aimed at analysing as broad a spectrum of various chemical compounds as possible. Confirmatory methods are more specific and are characterised by a lower limit of detection (LOD) and limit of quantification (LOQ) than screening methods. 

Material Selection of appropriate material for examination is mainly determined by the time that has elapsed from administration of the toxic substance to collection of the material, as well as the site of conducting examinations (a clinical or forensic laboratory, or the site of the incident, for example, during a roadside check of a driver). Various compounds occur in various materials - parent, and active and inactive metabolites. Active metabolites influence life processes, and the presence of inactive metabolites in the organism could attest to consumption of a substance a long time ago. Currently available analytical techniques are applied to detect, identify and determine chemical substances in classical biological material (i.e. blood, urine and sections of internal organs) as well as in so-called alternative materials (i.e. hair, saliva and sweat). In recent years, numerous studies aimed at 

Sometimes the amount of material delivered for examination is very limited for completely unjustified reasons. When developing methods, analysts take this fact into account. Increasingly frequently, blood samples of only 1 mL are collected for screening analyses, whereas as little as 0.1 mL blood is sampled for targeted or confirmatory analyses. 

Directions of Analysis Analytical procedures depends on the type of problem set. Unknown circumstances of an event or an unknown toxic factor require the application of systematic toxicological analysis (STA), so that the analytical procedure encompasses as many toxic substances as possible. In cases where the administered toxic compound is known, first of all a course of analysis targeted at this compound is conducted, and a positive result must be confirmed by another independent method. When working on a case in which only the symptoms of the action of an unknown toxic factor are given, the ability to use complementary techniques as well as knowledge of the fields of medicine, pharmacology and pharmacokinetics are of particular importance [53]. 

ICh tests have many advantages they are very sensitive, rapid, do not require pre-treatment of the biological material (which they are designed to analyse), and use small quantities (0.01-0.1 mL) of body fluids. Their principal drawback is low specificity. 

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