Forensic Toxicology. dr Marta Siczek Department of Forensic Medicine Wroclaw Medical University

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1 Forensic Toxicology dr Marta Siczek Department of Forensic Medicine Wroclaw Medical University

2 Introduction: Forensic toxicology encompasses the analysis of drugs and chemicals including the most common drugs of abuse and also focuses on the interpretation, that is, the understanding and appreciation of the results of this testing in a medical legal context. The results of toxicology testing are often presented to courts for the adjudication of an issue but are very often misunderstood. We need to remember that a test is not a test. A test result is only as good as the question it is asked to answer. Toxicology test results must, therefore, be introduced by qualified toxicologists. The traditional specimens used in testing include blood or its component parts, that is, plasma or serum, and urine. This is in part because these are the easiest to collect. In addition, in the case of blood, or its components, it represents the dynamic state of drug distribution in the body with the best relation to the state of the individual s pharmacologic condition (therapeutic, impairment, and death). In the case of urine, we have a static fluid that generally does not correlate with the pharmacological effects in an individual, rather it represents high concentrations of drugs and metabolites and demonstrates prior use. Thus, the ready accessibility and knowledge of the pharmacokinetics and distribution of drugs caused toxicologists to focus on these specimens.

3 Biological evidence possible to preserve and use in toxicological analyses. Material should include: Place of xenobiotic penetration into the body Blood which distributes xenobiotic to the organs Place of xenobiotic elimination Place of a possible xenobiotic accumulation To the untargeted study we take: stomach gastric buffers the small intestine (small bowel) the content of the small intestine blood liver bile kidney urine It s recommended by the Polish Society of Forensic Medicine and Criminology to take 50 g of tissue and 30 ml of tissue fluids

4 Packing for storing the taken material for toxicological studies has to be: Chemically pure and inert Hermetically sealed The material should be properly described. The description should include information such as: Name of deceased Age (if known) or date of birth Type of material Date of autopsy Name of doctor who performed autopsy The registration number of books autopsy

5 Toxic substances classification for the forensic purposes. The degree of toxicity extremely toxic highly toxic Lethal dose for an adult human a few drops teaspoon medium toxic 3 or 30 cm 3 a little toxic practically nontoxic g 1 dm 3 or 1 kg practically harmless over 1 kg or 1 dm 3 Classification by Prof. S. Raszeja Medycyna sądowa

6 Artemisia absinthium Artemisia absinthium (absinthium, absinthe wormwood, wormwood, common wormwood, green ginger or grand wormwood) is a species of Artemisia, native to temperate regions of Eurasia and Northern Africa and widely naturalized in Canada and the northern United States. It is grown as an ornamental plant and is used as an ingredient in the spirit absinthe as well as some other alcoholic drinks. Artemisia absinthium contains thujone, a GABA A receptor antagonist that can cause epilepticlike convulsions and kidney failure when ingested in large amounts. Green fairy Edgar Degas Dans un café l'absinthe 1873

7 Forensic Toxicology of Ethyl Alcohol According to statistics of the National Highway Traffic Safety Administration, persons were killed in alcohol-related accidents in This constitutes 40.9% of all people killed in traffic accidents that year. If one counts only those deaths in which one or more persons had a blood alcohol content above the legal limit of 0.1% at the time of the accident, the figure of alcohol-related deaths is reduced to 13,395, or approximately 32% of all fatal crashes. In comparison, approximately 15% of total road deaths in Great Britain involve accidents in which one or more people have a blood alcohol content (BAC) over the legal limit of 0.08.

8 The ethanol concentration exceeds 1 in 50% of drivers responsible for accidents; in about 30-40% of them the ethanol level exceeds 1.5

9 EtOH concentration in breath concentration [mg/l] *2,1 = in blood concentration [ ]

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11 State after consuming ethanol occurs when the alcohol content in the body is or leads to: 1) blood alcohol content from 0.2 to 0.5 or 2) from 0.1 mg to 0.25 mg of alcohol in 1 dm 3 of breath Drunk state occurs when the alcohol concentration in the body is or leads to: 1) blood alcohol content above 0.5 of alcohol or 2) the presence of exhaled above 0.25 mg of alcohol in 1 dm 3

12 Erik M. P. Widmark ( , Sweden) was among the first researchers to study in a systematic way the absorption, distribution, and elimination of ethanol in the body; in addition, he formulated his results in mathematical terms. Widmark's research during the first decades of last century paved the way for innovative traffic safety legislation that stipulated punishable limits of alcohol in the blood of a person driving a car. Widmark equation: A [g] = c max [ ] W [kg] r

13 Retrospective calculations: Data: EtOH concentration in blood at specific time (t x ) Result: EtOH concentrations before t x (for example 3 hours before) C tx-3 = C tx - β 60 x t [h] Prospective calculations (Widmark equation) Data: mass of absorbed alcohol [g], body mass [kg], distribiution coefficient (age, sex, height) Result: maximum concentration of EtOH C max [ ] = A [g] / (W [kg] r)

14 Retrospective calculations can be performed in cases which meet the the following conditions / limitations: 1) the concentration of alcohol in the blood (or breath) during the first study must be higher than , 2) the duration of the event to the first study can not be longer than 5-6 hours 3) At the time the event suspect must be in the elimination phase of alcohol (how do we know that?), 4) the suspect should not consume alcohol between the event and studies of concentration of alcohol. 5) Samples are collected and analysed with use of evidence method

15 Legal regulations of drugs using in Poland The phenomenon of drug addiction is regulated by the Act of 29 July 2005 on counteracting drug addiction (with further amendments), which replaced two former major acts: 24 April 1997 on countering drug addiction and Act of 31 January 1985 on prevention of drug addiction. Within the framework of the system and reform of the state s competences, the realization of some tasks regarding drug prevention remained with the central bodies of the state administration, while the local governments were obliged to implement educational and preventive programs. The forms of educational and preventive actions focusing on the promotion of healthy lifestyles were defined. The principle of voluntary and free treatment was maintained; rights were established for substitution treatment, and for treatment, rehabilitation and re-adaptation of addicts in detention centres and prisons as well as under arrest. In addition, the possibility to initiate treatment in the preliminary phase, i.e. before sending the case to the court by the public prosecutor, was established. The control of precursors was introduced and the unauthorised production and possession of precursors was criminalized.

16 The main legal texts in force now can be divided into the following groups: 1. Act of 29 July 2005 on countering drug addiction; 2. executive acts on treatment of addicts, treatment in prisons and arrests, lists of relevant medical professions, conditions of treatment; 3. regulation on the Council on countacting drug addiction; 4. regulation on National Programme on Counteracting Drug Addiction; 5. regulation on production, procession, import, export and circulation of narcotic drugs, psychotropic substances and precursors; 6. regulation on cultivation of poppy seeds and hemp; 7. major international agreements on drugs to which the Republic of Poland is a party.

17 Controlled substances The Act of 29 July 2005 on counteracting drug addiction includes two appendices. The first one covers the list list of narcotic substances that are divided into following groups: I-N, II-N, III-N and IV-N. The seond one covers the list of psychotropic substances that are divided into following groups: I-P, II-P, III-P and IV-P. All the lists and relevant groups follow the pattern used in the international agreements. The previously attached list of precursors has been removed following accession of Poland to the EU. Currently the Act refers directly to the Regulation 273/2004/EC as regards precursos. Drug use and possession The use of drugs itself is not penalised. However, any possession of drugs is penalised (art. 62.1). In cases of minor importance, the offender can be fined or ordered a limitation of liberty ( or deprivation of liberty up to one year maximum (art. 62.3). The fine is ordered in so-called daily rates (the minimum number of daily rates is 10 and maximum is 360) and the court decides how much one daily rate shall be. Nevertheless, as a rule, one daily rate shall not be smaller than 10 PLN (approx. 2.50) and not exceed 2000 PLN (approx. 500). The Act of 29 July 2005 on counteracting drug addiction (further amended) is generally an act of an preventive and treatment-oriented character, and so the aforementioned sanctions should not be used against addicts, though the criminal sanctions concerning the drug crimes were extended. The priorities on which the law and implementing actions are concentrated, according to the art of the Act, are education and prevention; treatment, rehabilitation and re-adaptation of addicts; control over the substances that may lead to drug addiction; fight against drug-related criminality; control over the cultivation of plants whose use can lead to drug addiction; limitation of health damages that are caused by the use of narcotic drugs or psychotropic substances.

18 Art. 4, point 11) of the Act of 29 July 2005 on counteracting drug addiction defines the term drug addiction. According to the definition, it means chronic or habitual use for other than medically warranted purposes of narcotic drugs or psychotropic substances or substitute drugs having an addiction-forming or addiction-sustaining liability. Additionally, in art. 6, point 29) of the aforementioned Act, the term dependence on narcotic drugs or psychotropic substances is defined. It means a syndrome of psychic or physical symptoms, caused by the action of such drugs or substances upon the human organism, typified by altered behaviour or other psycho-physical reactions and the necessity for chronic or habitual use of such drugs or substances in order to experience their influence upon the mind or to avoid the consequences caused by their deficiency. As stated above, the previously attached list of precursors has been removed from the Act of 29 July 2005 on counteracting drug addiction, following accession of Poland to the EU. Currently the Act refers directly to the Regulation 273/2004/EC as regards precursos. Nevertheless, the production, procession as well as import, export and circulation of precursors requires a permit, which should be retained by all those subjects that have been granted the permit. Only the properly marked precursors can be circulated. Retail of precursors can be done only by pharmacies. The control over precursors and the issue of permits belong to the Pharmaceutical Inspection, which is run by the General Pharmaceutical Inspector. It is a central organ of governmental administration supervised by the Minister of Health.

19 Drugs of abuse how can we categorise them? Synthetic / natural Ways of administering Chemical properties Addictive (more / less) Ways of action

20 Drugs of abuse main groups of interest in our laboratory THC, tetrahydrocannabinol, marihuana ( )-(6aR,10aR)-6,6,9-Trimethyl-3-pentyl-6a,7,8,10a-tetrahydro- 6H-benzo[c]chromen-1-ol 1 ng/ml state after consuming 5 ng/ml state under inlfuence

21 Drugs of abuse main groups of interest in our laboratory Main metabolites of THC: 11-hydroxy-THC 11-nor-9-carboxy-THC

22 Drugs of abuse main groups of interest in our laboratory THC effects of using Euphoria Anxiety distortions in the perception of time and space increased heart rate dry mouth reddening of the eyes sensation of cold or hot hands and feet the feeling of increased appetite

23 Drugs of abuse main groups of interest in our laboratory Amphetamine Amphetamine derrivatives: MDMA (3,4-methylenedioxy-methamphetamine) aka ecstasy, XTC, E Tenamfetamine (MDA, 3,4-methylenedioxy-amphetamine aka Sally, Sass

24 Drugs of abuse main groups of interest in our laboratory Central nervous system stimulant Party drugs Hipertention increased heart rate faster and deeper breaths blurred vision dry mouth excessive grinding of the teeth Sweating increased alertness, concentration decreased sense of fatigue mood swings insomnia

25 Drugs of abuse main groups of interest in our laboratory Opiates morphine codeine thebaine anelgesic alkaloids

26 Drugs of abuse main groups of interest in our laboratory Opioids Heroin (morphine diacetate) (semi-synthetic) Fentanyl, brand name: Durogesic (synthetic) treandsermal patches used for relief of pain during palliative care

27 Drugs of abuse main groups of interest in our laboratory Cocaine aka benzoylmethylecgonine Strong stimulant, recreational drug loss of contact with reality an intense feeling of happiness a fast heart rate Sweating large pupils very high blood pressure High body temperature

28 Drugs of abuse main groups of interest in our laboratory benzodiazepines sedative, hypnotic (sleep-inducing), anxiolytic (anti-anxiety), anticonvulsant, and muscle relaxant the core structure of benzodiazepines