Novel Psychoactive Substances: Challenges and choices · PDF fileNovel Psychoactive Substances: Challenges and Choices in Forensic Toxicology . Julia M. Pearson, PhD, F -ABFT . Chief
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Novel Psychoactive Substances: Challenges and Choices in Forensic Toxicology
Julia M. Pearson, PhD, F-ABFT
Chief Forensic Toxicologist
Hillsborough County Medical Examiner
Tampa, FL
Forensic TOXICOLOGY
The Study of Poisons for Forensic Toxicology
The study of the effects of chemical substances on living systems
Forensic test results are subject to challenge in our adversarial justice system
For forensic toxicology use only.
All substances are poisons; there is none which is not a poison. The right dose differentiates a poison and a remedy
Paracelsus (1493-1541) Poisons and medicines are often times the same
substance given with different intents. Peter Mere Latham (1789-1875)
For forensic toxicology use only.
Volatiles Gases Acid/neutral/basic compounds Hydrocarbons Halogens Polar and non-polar Lipophilic and hydrophilic Conjugates or glucuronides Small and large molecules Thermally stable and labile Heavy metals Extremely potent drugs (ng/mL or pg/mL range) There is not a single analytical instrument that can analyze for all these various analytes
Types of Substances Analyzed in Forensic Toxicology
For forensic toxicology use only.
Forensic Toxicology Analysis Screen
An initial test to distinguish negatives from presumptive positives
Immunoassay, color tests, GCMS, LC-MS/MS, LC-TOF
Confirmation A second test used to definitively identify a drug or chemical
Usually mass spectral based techniques
Quantitation A test used to identify the amount of drug present in the specimen
Immunoassay, chromatographic or mass spectral based techniques
General Rule in Forensic Analysis The detection of drugs should be confirmed (whenever possible) by a second
analysis preferably based on a different analytical principle.
For forensic toxicology use only.
Analytical Method Validation Parameters
Accuracy (bias) Precision Limit of detection Limit of quantitation Interference studies Calibration model Carryover Ionization suppression/enhancement (LC techniques) Dilution integrity Stability
Data from United Nations Office of Drugs and Crime Early Warning Advisory on New Psychoactive Substances (Jan 2015)
Analytical Challenges Associated with Novel Psychoactive Substances Is a standard available? Cost of the analytical standard? Mass spectral library? Published analytical methods? Published case studies to help interpret results? Staffing resources available to analytical forensic method
development and validation (estimated 3-6 months)? Is it cost effective to develop forensic method or send to a private
reference laboratory?
For forensic toxicology use only.
Immunoassays
Inexpensive, rapid tests to screen for specific drugs or drug classes Can be very sensitive (especially kits developed for blood and oral fluid) Requires a known standard and antibody to develop an immunoassay
(make take several months to years to develop a new immunoassay to a new psychoactive substance)
Manufactured commercially
Some new designer drugs cross-react with immunoassays for other similar classes of drugs Cathinones may cross-react with methamphetamine immunoassay
Fentanyl may cross-react with fentanyl immunoasssay
For forensic toxicology use only.
Some Designer Stimulants
Cathinones Tryptamines Benzofurans Methylone 5-MeO-DALT 5 APDB Mephedrone 5-MeO-DIPT 6 APDB Methedrone 5-MeO-DMT 5 APB MDPV DMT 6 APB Butylone Ethylone Pentylone
Fentanyl, Acetyl Fentanyl and Butyryl Fentanyl
Fentanyl
Butyryl Fentanyl
For forensic toxicology use only.
Full Scan Electron Impact (EI) Gas Chromatography Mass Spectrometry (GCMS)
EI full scan GCMS
Used extensively for decades in analytical forensic toxicology laboratories, ‘gold standard’
All analytes eluting from column are hit with a beam of electrons at 70 eV so fragmentation pattern is identical on all instruments
Several hundred thousands of chemicals are published in searchable full scan GCMS libraries (NIST, SWGDRUG, AAFS, Maurer Wiley and websites)
Libraries must be periodically upgraded to include new compounds Analysis performed is gas phase so analytes amenable to GCMS analysis are
typically small, volatile, thermally stable and non-polar To maximize sensitivity, targeted analysis can be conducted using selected ion
monitoring (SIM) mode Straightforward, simple operation (or more so than LC-MS/MS or TOF) Sensitivity µg/mL to ng/mL range Cost ~ $50,000 to $150,000
For forensic toxicology use only.
CASE STUDIES IN WHICH GCMS ANALYSIS IDENTIFIED THE NPS
LSD Methylone and 5-APDB 25I-NBOMe Fentanyl analogs
For forensic toxicology use only.
LSD Poisoning Case • A family of four (including a mother in her ninth month of pregnancy)
became ill after consuming a home cooked meal of steak fajitas.
• Initial symptoms included tingling in arms and legs, nausea, dizziness, tachycardia, dilated pupils and hallucinations.
• The family drove to a nearby hospital where they were admitted. • All victims (including the newborn infant) recovered spontaneously with 24
hours after admission and were released within a few days.
• Hospital urine drug test results were negative.
For forensic toxicology use only.
LSD Poisoning Case
All four victims’ hospital blood and urine samples were analyzed for 12 classes of drugs of abuse by immunoassay Acetaminophen, barbiturates, benzodiazepines, carisoprodol/meprobamate,
cocaine metabolite (benzoylecgonine), cannabinoids, fentanyl, methadone, methamphetamine, opiates, oxycodone and salicylates.
All results were negative.
All four victims’ hospital blood and urine samples were analyzed by full scan electron impact GCMS. All results were negative.
For forensic toxicology use only.
The suspected ‘tainted’ meat package
For forensic toxicology use only.
LSD Poisoning Case
• LSD was identified on the ingested steak fajita meat by GCMS analysis.
• Targeted analysis for LSD in urine by LC-MS/MS confirmed the presence of LSD in three of the victims’ samples (the fourth victim’s urine sample had insufficient volume for LSD analysis).
• Once the LSD was identified on the steak fajita meat, the case was taken over by the FDA for specialized testing.
• FDA has confirmed the presence of LSD on the steak fajita meat and the case is the source of the LSD was never determined.
For forensic toxicology use only.
Methylone Case 1 23 year old male Walking in and out of traffic at major intersection,
banging on cars with fists, screaming profanities, yelling rap songs
Refuse to cooperate with police, combative, resisted arrest, police used taser (missed) and tackled him to ground
Transported to ER Body temperature 105.9° F Seizures Cardiac arrest Rhabdomyolysis Multiple organ failure Died 24 hrs after admission
Post Mortem Samples were tested
Methylone Case 2
19 yr old female at club in Kansas City Witnessed to take a pill called “Molly” Collapsed with seizures Taken to ER
Body temperature 103.9° F Asystole Despite resuscitation efforts pronounced dead 8
minutes after admission Post Mortem Samples were tested
For forensic toxicology use only.
Methylone Case 3
23 yr old male after after-hours club Witnessed to take “LSD” Acting irrational, sweating, bad trip, freaking out Management facilitated his removal by “saran
wrapping” him to chair and place him in chair into the back of his friend’s van
4 hours later another friend found him in the van Transported to ER
Body temperature 107° F Heart rate 132 Acidotic Pronounced dead 45 minutes after admission
Post Mortem Samples were tested
For forensic toxicology use only.
Methylone Analysis In all three cases, immunoassay was positive for methamphetamines
yet no amphetamines or methamphetamines were detected.
GCMS identified an early eluting unidentified peak that was determined to be methylone
For forensic toxicology use only.
Designer Drug Cases
2
1
10
2
0 0 0 0
4
6
1
0
2
4
6
8
10
12
2011 2012 2013 2014 2015
Designer Drug Cases
Methylone Ethylone Alpha-PVP
Synthetic LSD
For forensic toxicology use only.
Case Report 25I-NBOMe 20 yr old male Usually the “trip sitter” for friends while they did “LSD” On date of incident, deceased decided to use “LSD” Went crazy, freaking out, running through woods Several hours later someone reported hearing “Oh shit” and
thud Deceased found lying on pavement surrounding swimming
pool. It is believed he fell from 7th floor balcony. Drug screen (including LSD) were negative. 25I-NBOMe not detected using standard toxicology
procedures 25I-NBOME was identified on “LSD” blotter paper by GCMS Targeted analysis by LC-MS/MS confirmed 25I-NBOMe in
biological specimens
For forensic toxicology use only.
Fentanyl GCMS Full Scan EI
14_07590_URINE #4764 RT: 15.26 AV: 1 SB: 2 15.17 , 15.32 NL: 2.28E7T: {0,0} + c EI Full ms [43.00-550.00]
50 100 150 200 250 300 350m/z
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
Relativ
e Abun
dance
146.1
245.2
189.2
105.1
44.157.0
96.177.1246.2202.1132.1 158.191.1
118.170.1
159.1 203.1 247.2 282.0244.1 331.0316.1 340.1298.0
Fentanyl
For forensic toxicology use only.
Acetyl Fentanyl GCMS Full Scan EI 14_07590_URINE #4588 RT: 14.96 AV: 1 SB: 243 14.62-14.89 , 15.02-15.16 NL: 2.03E7T: {0,0} + c EI Full ms [43.00-550.00]
50 100 150 200 250 300 350m/z
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
Relati
ve Ab
undanc
e
231.2
146.1
188.1
44.1
105.1158.1
77.1 189.296.1
118.191.1 232.2132.1
79.170.1
69.1 159.1 207.1233.2 343.0315.0282.1172.2 208.1 295.1266.1
For forensic toxicology use only.
Butyryl Fentanyl GCMS Full Scan EI 15-06440_D #4691-4720 RT: 14.63-14.69 AV: 30 SB: 1227 13.47-14.49 , 14.87-15.98 NL: 7.44E4T: {0,0} + c EI Full ms [43.00-550.00]
60 80 100 120 140 160 180 200 220 240 260 280 300 320 340m/z
0
5
10
15
20
25
30
35
40
45
50
55
60
65
70
75
80
85
90
95
100
Relat
ive Ab
unda
nce
146.244.1
105.1
77.1
55.1189.2
71.1 259.391.1
98.2132.2118.1
82.1 153.4260.3190.1158.2 186.3 216.3144.3 172.2 236.3199.2 309.0246.4 270.6 323.1 354.2287.1 333.2
Butyryl Fentanyl
For forensic toxicology use only.
Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS)
LC-MS/MS Becoming more popular since they are easier to use and more affordable
than before Extremely sensitive ng/ml to pg/mL range Can analyze larger, non-volatile, thermally labile and polar molecules
(unlike GCMS) Targeted analysis scanning for precursor ions and then fragmenting to
product ions (selected reaction monitoring (SRM) or multiple reaction monitoring (MRM)
Subject to ion suppress/enhancement from matrix components that can interfere with ionization during electrospray
Since the voltages on electrospray and collision energies vary depending on analytes, LC-MS/MS libraries are not transferable between instruments and must be established on each instrument
LC-MS/MS better suited for targeted analysis and not unknown screening Price range approximately <$200,000 to $300,000
For forensic toxicology use only.
LC-MS/MS Forensic Applications
Cocaine, Cocaethylene, benzoylecgonine quantitation Opiate quantitation Benzodiazepine quantitation Cannabinoid quantitation Targeted 25I-NBOMe analysis of biological specimens (pg/mL) Targeted LSD analysis in biological specimens (pg/mL) Targeted fentanyl analogue analysis in biological specimens
(pg/mL)
For forensic toxicology use only.
LC-MS/MS Forensic Analysis of blank blood versus 0.5 ng/mL fentanyl control
For forensic toxicology use only.
Liquid Chromatography High Resolution Mass Spectrometry (LC-HRMS) Liquid Chromatography Time of Flight (LC-TOF) or Quadrupole Time of Flight (Q-TOF) Liquid Chromatography Orbitrap MS or Quadrupole Exactive (Q Exactive) MS
For forensic toxicology use only.
Liquid Chromatography High Resolution Mass Spectrometry (LC-HRMS)
GCMS and LC-MS/MS typically have mass resolution of approximately 1 amu (285 ± 1 amu)
HRMS has mass resolution of 0.0001 to 0.001 amu (1-10 ppm) or better
Can be used for general unknown screening to identify the structure of an unknown analyte
HRMS can distinguish between chemicals with similar masses Morphine (285.1365) and 7-aminoclonazepam (285.0669)
Usually used in tandem with a quadrupole and collision cell to get some fragmentation
Newer instruments, laboratories inexperienced with the technology, pretty complicated to use
Approximate cost >$200,000 - $300,000
For forensic toxicology use only.
Schematic of LC Q Exactive (Focus)MS
For forensic toxicology use only.
Schematic of LC-QTOF
Liquid Chromatography High Resolution Mass Spectrometry (LC-HRMS)
HRMS cannot distinguish between isobaric compounds Morphine (285.1365) and hydromorphone (285.1365) Cocaine (303.1470) and scopolamine (303.1470) Hydrocodone (299.1521) and codeine (299.1521) Phentermine (149.1204) and methamphetamine (149.1204) JWH-019 (355.1939) and JWH-122 (355.1939) JWH-016 (341.1779) and JWH-018 (341.1779) Butylone (221.1051) and Ethylone (221.1051) Amitriptyline (277.1830) and EDDP (277.1830)
For isobaric compounds must use retention time and fragmentation or other mass spectral technique for definitive identification
For forensic toxicology use only.
Comparison of GCMS, LC-MS/MS and LC-HRMS GCMS LC-MS/MS LC-HRMS
Screening Full scan Targeted Full scan Analytes Small, volatile,
thermally stable, non-polar
Small or large, non-volatile, thermally unstable and polar
Small or large, non-volatile, thermally unstable and polar
Resolution 1 amu 1 amu 0.001-0.0001 amu Libraries Large,
transferable Smaller, non-transferable
Smaller, non-transferable
Analyte identification
EI full scan spectra and retention time
MS/MS fragmentation and retention time
Exact mass, isotope pattern, fragmentation and retention time
Cost $ $$ $$-$$$
For forensic toxicology use only.
Designer Drugs
They are the wave of the future They are here to stay They will continue to be a legal and forensic
laboratory nightmare Synthetic drug chemists will always have an
advantage over legislation and labs Economics 101: Supply and Demand
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