FORENSIC TOXICOLOGY - Bio Medical Forensics

tramadol, closely followed by amitriptyline, its metabolite nortriptyline,
nordiazepam, acetaminophen, trazodone, and carisoprodol. Over half of
the decedents (66% of the "drug caused deaths" and 55% of the non-drug
caused deaths) were taking an antidepressant in conjunction with
tramadol. Similar patterns were observed in the drivers in whom antidepressants
were present in 38% of cases. There were several cases in which
death was attributed to the combination of tramadol with other drugs
affecting the reuptake of serotonin. These included tricyclic antidepressants,
and the selective serotonin reuptake inhibitors (SSRI's) fluoxetine,
and sertraline. As tramadol itself inhibits serotonin reuptake, this raises
the possibility of a serotonergic crisis (e.g. serotonin syndrome)
contributing to the actual mechanism of death. Another concern is a
metabolic interaction between tramadol and amitriptyline, which are both
metabolized by the cytochrome P4502D6 enzyme. This combination may
contribute to an elevation of tramadol concentrations even with
therapeutic administration.
Our data show that tramadol does appear to be a fairly safe drug
when taken alone, and that patients can survive concentrations in
considerable excess of the accepted therapeutic concentration, albeit with
significant apparent psychomotor effects on motor skills. Patterns of
prescribing of tramadol still appear to include the co-administration of
drugs that may have significant metabolic or pharmacological interaction,
and these should be carefully considered when interpreting postmortem
toxicological data.
Tramadol, Drug Interaction, Postmortem Toxicology
K26 Simultaneous Determination of the
Nerve Gases GB (Sarin) and VX and
the Vesicant HD (Sulfur Mustard)
Jimmie L. Valentine, PhD*, Teresa Evans, MS, and Charles F.
Fowler, PhD, Department of Pediatrics and Arkansas Children’s
Hospital, University of Arkansas for Medical Sciences, 800 Marshall
Street, Little Rock, AR, and Arkansas Department of Health (CFF),
4815 West Markham, Little Rock, AR
The goal of this presentation is to present methodology for rapidly
detecting exposure or contamination from the chemical warfare or
potential terrorist agents, GB (sarin), VX, and HD (sulfur mustard).
The U.S. as a signatory to the Chemical Weapons Convention plans
upon destroying the domestic stockpile of chemical warfare agents stored
at six different sites by 2007. Some of these storage sites, such as the Pine
Bluff (Arkansas) Arsenal, have substantial populations living near the
demilitarization facility. In the unlikely event that an accidental release
occurs, monitoring of persons potentially exposed and environmental contamination
will be necessary for assessing effects on public health. The
nerve gases GB (sarin) and VX are two of the chemical warfare agents
currently scheduled for destruction. These toxic gases are relatively easy
to synthesize and have previously been used for terrorist activities in
Japan. Additionally, it is known that several rouge nations supporting terrorist
activities also possess these nerve agents. The vesicant (blistering
agent) HD in addition to being in U.S. stockpiles slated for destruction is
also known to be in the possession of some rouge states. Therefore,
having an assay for detection of these chemical agents becomes important
in any forensic investigation following an incident.
GB and VX hydrolyze in the environment and are metabolized in
humans by essentially identical pathways. These organophosphates form
a common end product, methylphosphonic acid (MPA) which if identified
would indicate that either of these agents was utilized. More specific identification
was ascribed by determination of the immediate precursors to
MPA, either isopropylmethylphosphonic acid (IMPA) or ethylmethylphosphonic
acid (EMPA) derived from GB and VX, respectively.
HD also undergoes environmental hydrolysis and human metabolism in
* Presenting Author
identical manners and forms thiodiglycol (TDG) and thiodiglycol sulfoxide
(TDGS). Therefore, an analysis method that can detect MPA,
IMPA, EMPA, TDG, and TDGS can be utilized for multiple matrices by
modifying the pre-analytical work-up.
A GC-MS method was developed that simultaneously detects MPA,
IMPA, EMPA, TDG, and TDGS as their respective silylated derivatives
in a 10-minute analysis. For urine analysis, 100 µL of a 1,000 ng/mL
aqueous solution of d7-IMPA and d8-TDG was added as internal standards
to 3 mL of urine. Calibrators containing 3.1, 6.3, 12.5, 25, 50, and
100 ng/mL of MPA, IMPA, EMPA, TDG, and TDGS in laboratory
workers’ urine were used to determine replicate urine specimens to
which 0, 10, and 80 ng/mL of these hydrolysis compounds were added.
Following addition of the internal standards, 1 mL of 5% HCl was added
followed by extraction with 3 mL 9:1 CHCl3 :Isopropyl alcohol and centrifugation
to separate the organic layer that was evaporated to dryness
under nitrogen at 50°C. To the resultant residue was added 30 µL
BSTFA and 70 µL ethyl acetate followed by heating at 75°C for 15 min.
GC-MS conditions were as follows: injection volume 1 µL; injector port
180°C; interface 280°C; column, HP-1 (12m x 0.2 mm i.d.); oven
program 50°C for 4 min, 40°C/min, 280°C for 0.25 min; helium flow 0.5
mL/min; SIM mode with 50 ms dwell; and EM 400 volts above daily
tune. Retention times and ions (where q is the quantitative ion) were:
EMPA, 6.02 min, m/z 153 (q), 154, 137; d7-IMPA 6.15 min, m/z 154 (q),
171, 155; IMPA, 6.17 min, m/z 153 (q), 195, 169; MPA 6.39 min, m/z
225 (q), 226, 227; d8-TDG 7.81 min, m/z 119 (q), 183, 168; TDG 7.83
min, m/z 116 (q), 176, 130; TDGS 8.64 min, m/z 166 (q), 117, 267.
The LOQ of the developed method was 3.1 ng/mL for all the
analytes of interest and the LOD was 1.5 ng/mL. Because exposure of
humans to the nerve gases and vesicant constitute unethical experimental
paradigms, validation of the method will require the determination
of a baseline levels of the compounds in a substantial number of
non-exposed humans. TDG is known to occur at low levels in human
urine as a by-product of dietary habits. Once a background-level for all
the analytes is determined, a level of 2SD above the mean could be used
for indicating exposure.
Nerve Gases, Vesicant, Urine Analysis
K27 A Fatality Due to Lorazepam
and Morphine Intoxication
During Long Term Therapy
Francisco Diaz, MD*, Laureen J. Marinetti, MS, Bradford R. Hepler, PhD,
Daniel S. Isenschmid, PhD, and Sawait Kanluen, MD, Wayne County
Medical Examiner’s Office, 1300 East Warren, Detroit, MI
The objective of this presentation is to report the concentration and
distribution of both lorazepam and morphine in various specimens
collected from a single fatality after documented chronic high dose
treatment with both drugs for 17 days.
Content: A 48-year-old male was brought to the emergency room
complaining of chest pain/discomfort due to an alleged assault he had
sustained. Hospital records failed to document evidence of the assault,
a CT scan of the chest showed a “spot” on the lower lobe of the left lung
that was described as a small pulmonary contusion. He was subsequently
admitted to hospital, intubated and dosed IV with morphine, lorazepam
and propofol to sedation with plans to biopsy the lung for possible
pathogens. The patient had a history of active HIV with a low CD 4
count. The hospital also documented pneumonia. The patient was on
HIV medications and arrived at the hospital alert and talking. Multiple
biopsies, tissue cultures and other studies with special stains failed to
yield the pathogens usually seen in AIDS such as pneumocystis carinii
and cytomegalovirus. Antibiotics were administered for the pneumonia
and the patient remained on a ventilator for the entire course of his hos-
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