FORENSIC TOXICOLOGY - Bio Medical Forensics

K18 The Effects of pH on the Oxidation of
Ephedrine and Phenylpropanolamine
Using Sodium Periodate
Neil A. Fortner, MS*, Roger Rutter, BS, and Joseph Lane, BS,
PharmChem, Inc., 4600 North Beach, Haltom City, TX 76137;
Robert F. Turk, PhD, Center for Toxicology Services, Inc., 8231
Lakeshore Villa Drive, Humble, TX 77346
The attendees will better understand the impact that pH may have
on the oxidation of ephedrine and phenylpropanolamine using sodium
periodate.
The use of sodium periodate to chemically oxidize common over
the counter amphetamine like substances such as ephedrine, and phenylpropanolamine
has become an accepted practice in forensic urine drug
testing environments. However, very little information is available as to
the effect that pH has on the efficiency of this oxidative procedure. The
purpose of this study was to evaluate the potential of the production of
amphetamine and methamphetamine in the presence of high concentrations
(3,000,000 ng/ml) of ephedrine and phenylpropanolamine. A saturated
sodium periodate solution and sodium hydroxide solution are
added to the urine sample containing the drug and deuterated internal
standards. The pH of this oxidation step is between 11 and 13. In this
study, the sodium periodate was also adjusted to pH 4.4, 5.2, 9.1 and 9.3.
Samples were extracted using solid phase technology, and derivatized
with MBTFA to form the TFA derivative. GC/MS analysis was conducted
using electron impact ionization using three ions for the native
compound and two ions for the deuterated internal standard. A single
point calibrator at 500 ng/ml was used to establish both qualitative and
quantitative results. No amphetamine or methamphetamine was detected
at any of the pH levels evaluated. This data suggests that the oxidation
of ephedrine and phenylpropanolamine at levels as high as 3,000,000
ng/ml by sodium periodate is effective when the pH is between 4.4
and 13.
pH, Ephedrine, Phenylpropanolamine
K19 The Validity of Surrogate
Reporting of Substance Use
Hsiang-Ching Kung, PhD* and Jack Li, PhD, National Center for
Health Statistics, CDC, 3311 Toledo Road, Room 7318, Hyattsville,
MD 20782; Rong-Jen Hwang, PhD, Toxicology Laboratory Criminal
Investigations Division, Santa Barbara County Sheriff-Coroner, 66
South San Antonio Road, Santa Barbara, CA 93110
After attending this presentation, attendees will have an understanding
of evaluating the validity of surrogate reporting of substance
use for the deceased.This study contribute to the understanding of
factors involved in achieving high sensitivity and specificity of certain
substances when contesting the validity of next-of-kin reporting versus
toxicology reports.
Introduction: Collection of substance use information for those
who died unexpectedly often rely on proxy respondents or toxicology
reports. Past research have examined surrogate reporting about the
deceased characteristics. However, the direct assessment of proxy
reporting of substance use versus toxicology report were rarely investigated.
The purpose of this study were: 1) to use toxicology report as a
gold standard to evaluate the validity of proxy reporting of substance
use, and 2) to identify which drug groups that are more likely to be accurately
reported by the surrogate.
* Presenting Author
Methods: The data for this study were obtained from the 1993
National Mortality Followback Survey (NMFS) conducted by the
National Center for Health Statistics, Centers for Disease Control and
Prevention. With the permission from next-of-kin of the deceased, questionnaire
data were linked to 3483 toxicology report collected from 1265
medical examiner/coroner offices. Ten items that asking the deceased
substance use behavior were selected from questionnaire and compared
with toxicology report. In the interview questionnaire, substances were
grouped into nine drug categories : alcohol, pain killer, sedative, tranquilizer,
antidepressant, stimulant, cocaine, marijuana, and methadone.
Sensitivity and specificity test were used to evaluate the validity of nextof-kin
reporting. We defined sensitivity is the toxicology report GC/MS
confirm positive of a substance used and next-of-kin also reported yes to
that substance for the deceased. Specificity is the toxicology report
GC/MS confirm negative of a substance used and next-of-kin also
reported no to that substance for the deceased.
Results and Discussion: The study results in the table below
demonstrated that methadone and painkillers such as morphine, codeine
and propoxyphene had 100% sensitivity. High sensitivity reflects that
immunoassay procedures and confirmation techniques for these two categories
of substance that were well developed and routinely executed for
their identification in the laboratory. However, the sensitivity for other
categories of substance use was low. The possible explanation for low
sensitivity could be: 1) inability of the laboratory to detect substances
that were not routinely screened and confirmed; 2) each substance has
an unique halflife.
Consumption of substances such as methamphetamine, cocaine, or
alcohol few days prior to death often provides a negative lab result; 3)
small quantity of substance use frequently causes a lab result below the
detection limit; 4) detection time also varies depending upon analytical
method used, drug metabolism, individual’s physical condition, fluid
intake, and method and frequency of substance ingestion prior to death.
Furthermore, cutoff values for positive substance vary from one laboratory
to another. Regarding specificity, the survey revealed an average
76% specificity indicating that proxy reporting of substance use has
some degree of scientific certainty in general. However none of the individual
categories of substance reached 100% specificity, meaning proxy
respondents did not know whether the decedents had used substance
prior to their death. Alcohol, on the other hand, has the lowest specificity.
It is probably associated with proxy’s social, financial, psychological
and legal implications. In conclusion, our study showed that both
the toxicology report and proxy reporting provided important information
in identifying forensic relevance for those who died unexpectedly.
Nevertheless, shortfalls of each reporting system should be
cautiously taken into consideration in result interpretation.
Sensitivity Specificity
Alcohol 0.93 0.26
Pain Killer 1.00 0.73
Sedative 0.36 0.88
Tranquilizer 0.47 0.85
Antidepressant 0.60 0.75
Stimulant 0.41 0.93
Cocaine 0.59 0.85
Marijuana 0.58 0.80
Methadone 1.00 0.90
Validity, Toxicology Report, Surrogate Reporting
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