Drug abuse and toxicology screening

Dr. Mohamed AL-TufailHead of toxicology laboratory, KFSHRC

1

2

Systematic toxicological analysis (STA) is a major part of the examination in clinical toxicology. STA is aimed at detecting and identifying all substances of toxicological relevance (i.e. drugs, drugs of abuse, poisons and/or their metabolites) in biological material. Particularly, gas chromatography–mass spectrometry (GC/MS) is a routinely applied screening and confirmation tool in STA. There is clear trend, however, to complement existing GC/MS procedures with liquid chromatography-mass spectrometry (LC/MS) assays. One competent LC/MS-based approach for untargeted screening analysis makes use of MS/MS under data-dependent acquisition control (DDA) to identify compounds by subsequent library search

3

ALCOHOL

4

Alcohol Analysis

Equipment: Headspace GC-MS

BLOOD ALCOHOL URINE ALCOHOL

5

Basic Pharmacology of Alcohol (ethyl alcohol)

Non-potent compound: 80 mg/dL (0.08%)

Nonspecific compound: (1) Potentiates the inhibitory effects of the transmitter GABA by altering the conformation of the heteropentameric GABAA receptor and increases Chloride ion entry into neurons.

(2) Inhibits the activation of NMDA-type glutamate receptors reducing Sodium and Calcium ion entry into neurons.

6

Basic Pharmacology of Alcohol (con’t)

Acute: produces dose-dependent intoxication, loss of behavioral inhibition, sedation, impaired judgment, slurred speech, ataxia. At higher doses: loss of consciousness, anesthesia, coma, respiratory depression, cardiovascular depression.

Chronic: hepatitis and cirrhosis, gastrointestinal bleeding, hypertension, thiamine deficiency.

Teratogenicity: fetal alcohol spectrum disorders.

7

Psychostimulants(cocaine & methamphetamine,

dextroamphetamine, methylphenidate)

8

Basic Pharmacology of Psychostimulants

(cocaine & methamphetamine, dextroamphetamine, methylphenidate)

Indirect acting sympathomimetics: block the reuptake of the neurotransmitters: dopamine, norepinephrine and serotonin

9

Basic Pharmacology of Psychostimulants (con’t)

- Acute: arousal, euphoria, agitation, restlessness, insomnia, anorexia, tachycardia, hyperthermia, seizures.

- Chronic: psychotic delusions and paranoia.

10

Marijuana and hashish

11

Marijuana Tetrahydrocannabinol (THC) is the Active alkaloid from the cannabis plant

Currently the most commonly used illegal drug Binds and activates abundant G-protein coupled receptors in brain (CB1 and CB2); reduces neuronal excitability by:

- increasing K+ conductance and - decreasing Ca+ + conductance

12

Basic Pharmacology of Opiates (heroin, morphine, oxycodone)

Mu, Kappa, and Delta types opioid receptors Mu receptor activation induces euphoria, Kappa

receptor activation produces dysphoria Enkephalins, Endorphins and Dynorphins are

the endogenous ligands that are released during stress to induce analgesia, immobility (sedation), euphoria or dysphoria.

13

Role of Opioids

14

Excretion Drugs are eliminated from the body either unchanged as the

parent drug or as metabolites (a changed form of the drug). Organs that excrete drugs eliminate polar compounds (water

soluble) more readily than components with high lipid (fat) solubility. The exception to this premise is the lungs.

Lipid soluble drugs are not readily eliminated until they are metabolized to more polar compounds.

Possible sources of excretion include: Breath Urine Saliva Perspiration Feces Milk Bile Hair

15

DRUG CLASS DETECTION TIME IN URINE

Amphetamine Stimulant Up to 2 days

Barbiturates depressants / sedatives / hypnotics

short-acting:  2 days

long-acting: 1-3 weeks

(based on half-life)

Benzodiazepines depressants / sedatives / hypnotics

therapeutic dose: 3 days

chronic use: 4-6 weeks or longer

Cocaine (benzoyl ecgonine metabolite)

Stimulant Up to 4 days

Codeine Analgesic / Opiate 2 days

Ethyl alcohol, ethanol depressants / sedatives / hypnotics

urine: 2 to 12 hours

serum/plasma: 1 to 12 hours

16

Heroin Analgesic / Opiate

2 days

Marijuana, Cannabinoids Hallucinogen Single use: 2 to 7 days

Prolonged, chronic use: 1 to 2 months or longer

Methadone Analgesic / Opiate

3 days

Methamphetamine Stimulant Up to 2 days

Methaqualone depressants / sedatives / hypnotics

Up to 14 days

MDMA(methylenedioxy- Stimulant Up to 2 days

methamphetamine)

Morphine Analgesic / Opiate

2 days

Phencyclidine Hallucinogen 8-14 days, but up to 30 days in chronic users

Propoxyphene Analgesic / Opiate

6 hours to 2 days

DRUG CLASS DETECTION TIME IN URINE

17

Hair Test for Cocaine 

It may have a positive result within 8 hours, or at times, only after 7 to days after cocaine use. The substance can remain on the hair for months, even until the hair is trimmed. Cannot be done by a single hair, the procedure requires a samples of hair around 5 inches long.

18

Elimination of Alcohol

The liver is responsible for the elimination - through metabolism - of 95% of ingested alcohol from the body. The remainder of the alcohol is eliminated through excretion of alcohol in breath, urine, sweat, feces, milk and saliva. The body uses several different metabolic pathways in its oxidation of alcohol to acetaldehyde to acetic acid to carbon dioxide and water.

Healthy people metabolize alcohol at a fairly consistent rate. As a rule of thumb, a person will eliminate 15 ml of alcohol per hour. Several factors influence this rate. The rate of elimination tends to be higher when the blood alcohol concentration in the body is very high.  Also chronic alcoholics may (depending on liver health) metabolize alcohol at a significantly higher rate than the average. Finally, the body's ability to metabolize alcohol quickly tend to diminish with age.

19

Toxicology screening and drug abuse analysis using GC-MS and LC-MS

Method Of Analysis

Extraction Clean up Concentration Injection on GC-MS or LC-MS Reporting

21

The extraction depends on the pKa of each component

So we have two Methods of extraction Acid and base extraction

Analysis for toxins and drug abuse in urine or blood or hair

22

Theoretically can separate drugs into 5 categories

◦Strongly acidic (low pH)◦Weakly acidic (pH 5 to approaching 7)◦Neutrals (pH around 7)◦Weakly basic (pH 8-9)◦Strongly basic (pH > 9)

23

1) Blood & Urine- single basic or acidic extraction

2) Urine 3 ways extraction- acid

- weakly basic & neutral - basic

24

Basic Extraction – GC/MS Screen

Blood + Base (NH4OH) + Toluene

BACK EXTRACTION (clean up)Toluene + Acid (H2SO4)

Aqueous fraction + Base (NaOH) + Toluene

GC/MS

25

CHROMATOGRAPHYchromatography is a separation process that is

achieved by distribution of the substances between a mobile phase and a stationary phase

Amobile A stationary

26

Mass Spectrometry

Powerful detector

can be teamed up with GC or HPLCGC/MS LC/MS

Requires very low pressure (10-5 Torr)

27

Cocaine and its Metabolites sampling

28

Acid and base properties of cocaine and its metabolites

29

Drugs of abuse detected in human hair, methods of detection

30

Drugs of abuse detected in human hair, methods of detection

31

32

LC-MS/MS

33

34

Instruments

LC-MSMS QTOF

35

36

LCMSMS (TSQ VANTAGE)

37

LCMSMS TSQ (QUANTUM ACCESS MAX)

38

Using GCMS instrument in Toxicology screening

39

Examples of toxicology screening

Sibutramin

Sample Number M:34-141 ( Capsules )

Containing

High Quantity of Procymidone ( Pesticide )

Procymidone concentration is 2700 ppbMaximum residue limit is 100 ppb .

Procymidone

Sample Number M:34-153 ( Herbal Powder )

Contains

2-Pyridinamine

Methyl Salicylate

Acetaminophen

Sample Number M:35-214 ( Herbal Powder )

Royal Honeycontaining Synthetic drug Tadalafil in Concentration of 1.8 mg/g

Tadalafil is sexual stimulant ( Commericially Cialis )

Royal HoneyContaining Synthetic drug Tadalafil

Tadalafil is sexual stimulant ( Commericially Cialis )

Sample Number M:34-152 ( Sliming )

Sibutramine

Sample Number M: 34-125-1Herbal Powder

Contaminated with

Aerobic plate count :

2.0x105 CFU/mL - Limit 105 CFU/mL

Yeast and Moulds : 4.0x103 CFU/mL - Limit is 103 CFU/mL

Enterobacteriaceae : 1.0x103 CFU/mL - Limit is 103 CFU/mL

Also contains high cocentration of Arsenic ( 411 ppb )

And high concentration of Lead ( 6472 ppb )

54

THANK YOU