The Toxicology Discipline of the Alabama Department of Forensic
Sciences provides assistance to local, county, state and federal law enforcement
agencies in Alabama in death and criminal investigations. This assistance
includes laboratory analyses of biological specimens for the presence of
drugs and poisons. The findings of these analyses may then be used to establish cause and
manner of death or to ascertain or to explain impairment or performance of an
individual pursuant to criminal activity.
The Toxicology Discipline currently receives and completes
in excess of 4000 cases annually. Specimens are submitted from autopsies
conducted by medical examiners associated with the Department. The bulk of
the remaining specimens are submitted by local police and county sheriff
departments, Alabama State troopers and county coroners. Any law
enforcement agency with jurisdiction in the State of Alabama may submit
specimens for examination. The goal for turnaround is to complete
100 % of non-homicide cases within 90 days and 100 % of homicide cases within 60
days of receipt in the laboratory. The current average turnaround time is 50 days from receipt in the laboratory with fewer than
5% exceeding 90 days. Current casework based on the nature of the investigation is represented below.
Scope of Analysis
The Toxicology Discipline conducts qualitative
and quantitative analyses. Qualitative analyses are used
to identify a particular substance in a specimen but not to determine how much of
the substance is present. Quantitative analyses are used to
identify a particular substance and to establish how much is present. Quantitative
analyses are more complicated than are qualitative analyses because the
procedures must be
calibrated and controlled for each particular drug. Because of this added
complexity and for the sake of timeliness, the Toxicology Discipline may report
qualitative findings without quantification or it may limit analyses to specimens where such
findings can be reasonably interpreted. Quite often, the mere presence of a
substance in a specimen is sufficient to answer the question whether it was consumed.
The Toxicology Discipline routinely conducts quantitative analyses for ethanol
(alcohol) and related volatiles such as acetone, methanol and isopropanol.
Headspace/gas chromatography (HS/GC) is employed for this purpose.
This method may be applied to both liquid (blood, urine, etc.) and non-liquid
(tissues, etc.) specimens and is specifically calibrated and
controlled for these volatile substances. Non-biological specimens such as
beverages may be analyzed as well. The Toxicology Discipline confirms
positive findings by repeat analysis with the same or another specimen collected
from the same subject.
The Toxicology Discipline also routinely conducts qualitative analyses for
prescribed and non-prescribed drugs. Some of the many drugs and drug classes detected during these analyses include
the sympathomimetic amine class
(amphetamine, methamphetamine, MDMA, ephedrine, etc.), cocaine and metabolites, opiate class
(morphine, codeine, hydrocodone, oxycodone, etc.), benzodiazepine class
(diazepam, alprazolam, etc.), barbiturate class (phenobarbital, butalbital,
etc.), cannabinoids (from marijuana), other analgesics (propoxyphene, methadone,
tramadol, etc.), antidepressants (amitryptyline, Prozac®, etc.), muscle relaxants
and sedatives (Soma®,
zolpidem, etc.). The Toxicology Discipline also routinely conducts analyses for carbon monoxide (as
carboxyhemoglobin). This list is not intended to be complete, rather it
represents only a small sampling of the substances that comprise the scope of
analysis. Please contact a laboratory for more specific information.
Because toxicological findings are used in Court, the analyses are
conducted according to legally defensible practices and methods.
All submitted specimens are maintained under
chain-of-custody and in a secure environment to preserve the material for the
intended analyses. Analyses are conducted in two phases. The presumptive
intended to provide indications whether a particular drug or drug class is present.
Specimens that appear to be presumptively positive are then subjected to the confirmation phase,
which is intended to provide more
definitive identification of the drug. Confirmation analyses are typically
conducted with methods that have greater specificity than do presumptive analyses
and which may examine the chemical structure of the substance as a means of identifying
it. Gas chromatography/mass spectrometry (GC/MS) and liquid
chromatography/mass spectrometry (LC-MRM MS) are routinely employed for this
purpose. If a specimen is initially subjected to analysis with
GC/MS or LC-MRM MS, a confirmatory analysis may be conducted by repeat analysis with another specimen collected from the
same subject. Positive drug findings are reported only when they
Interpretation of Toxicological Results
Toxicological analyses represent a tool for assessing the
degree of impairment exerted by a drug or combination of drugs on a consumer.
Because the ultimate degree of impairment is death, toxicological findings are used
as part of the determination of cause and
manner of death. In this light, the presence of one or more drugs at
concentrations significantly higher than those expected following
therapeutic doses may be considered, along with other anatomical conditions or
defects, in determining whether drug consumption caused or contributed to death.
Conversely, the lack of adequate drug in a subject may indicate non-compliance
to therapy and allow for the conclusion that death was due to conditions that
might otherwise have been survivable.
Toxicological findings may be used to assess lesser degrees
of impairment such as the performance of an individual pursuant to criminal activity. A common
application is to determine whether an individual has been driving
under-the-influence of ethanol (alcohol, DUI) and/or drugs (DUID). Toxicological findings may
also be used to determine whether the actions, behavior or demeanor of a homicide
victim or suspect were affected at the time of the incident and, thereby, offer potential mitigating circumstances in adjudication
of the crime.
In order to establish impairment from toxicological findings,
must include a relevant substance present within a relevant specimen. The
reason for this is that drugs exert their pharmacological effects when they are present in
a target organ or organ system.
A relevant (active) substance is one that exerts
pharmacological activity and parent drugs typically fit this
description. However, once ingested, normal biochemical processes within
the body act upon and convert
parent drugs into metabolites, which may or may not exert the same
pharmacological activity as the parent drug. Furthermore, metabolites may
co-exist with the
parent drug or they may persist after the parent drug has been converted or
eliminated. Consequently, only parent drug and
active metabolites are relevant substances for establishing impairment. That is not to say that the identification of inactive metabolites
is without value. Such may allow for, among other things, the distinction
between acute and chronic drug ingestion.
The most significant target organs of forensic toxicological interest are the brain and nerves that comprise the central and peripheral
nervous systems. Blood circulates within the nervous systems and as such,
is the most recognized, relevant specimen. Urine, which is commonly
subjected to toxicological analyses, does not circulate within the nervous
systems and, therefore, does not qualify as a relevant specimen with which to
establish impairment from a toxicological finding. Nevertheless, a
toxicological finding with urine may be used to establish consumption and,
depending upon the individual case and other evidence at hand, may be used to
explain certain observed behavior. Toxicological findings in tissues may
be considered in postmortem cases where sufficient medical literature exists to
relate such findings to death or impairment.
The effects of ethanol and drugs are continuous and
progressive, which means generally, the greater the dose, the greater the
effect. However, the progression of effects differs amongst individuals
because overall impairment is the collection of all the mental and physical
functional responses to ethanol and drugs which are not uniform. For
example, with depressant drugs, low doses will impair one's inhibitions, which
results in outwardly and visibly excited behavior. However, greater
doses overcome this excitation and result in lethargy, sleepiness, coma and
death from respiratory depression. The point where one subject appears
excited versus lethargic or lethargic versus comatose depends upon the
collective degree to which all of the subject's mental and physical functions
are affected. This difference is the result of individual biological
characteristics and tolerance (the resistance to some effects and
the physiological dependency on continued doses acquired through frequent and
repeated exposure to ethanol and/or drugs). Therefore, while it may be said
that people respond differently to drugs (and ethanol), the truth is that people
respond the same but to different degrees.
There is a well-documented direct relationship between one's
blood ethanol concentration and one's ability to operate a motor vehicle.
Such relationship is reflected in the DUI per se laws. With drugs,
there is also a well-documented direct relationship between one's blood drug
concentration and the effect on one's task performance. However, because the degree of effect amongst individuals is
so much more varied with drugs than with ethanol, definitive per se
limitations are more difficult to establish scientifically and to apply legally.
Some jurisdictions have zero-tolerance statutes for DUID whereas others employ
the expertise of a toxicologist in Court to reconcile performance
impairment with the presence a drug or combination of drugs.
Specimens may be submitted to the Toxicology Discipline in
person or by
common carrier such as the US Postal Service, UPS, FedEx, etc. The Department
distributes kits, which contain the appropriate tubes, needles, seals,
documentation, instructions and address labels for this purpose. There are
two types of kits, one for collecting
specimens from live subjects and a second for
postmortem specimens and is intended for Coroners. Individual
specimens should be labeled with the name of the subject/suspect and packages
should be sealed and initialed.
Submission documentation should be sufficiently completed to allow the laboratory
to determine the nature of the case and the most appropriate examinations to
conduct. Completed documentation should be inserted into the pouch affixed to the outside of the kit. Kits should be sealed and initialed then
submitted to the laboratory.
The antemortem kit is intended for collection of specimens from live subjects and is appropriate for submission of specimens in DUI
investigations. This kit contains two 10-mL gray-stopper blood collection tubes and one 100-mL plastic urine cup. The kit also contains a needle,
alcohol-free cleansing wipes and seals. The tubes contain sodium fluoride preservative and potassium oxalate anticoagulant. Two completely-filled
tubes are recommended for a complete scope of analyses. Urine collection is optional, but highly recommended, especially when gammahydroxybutyrate (GHB)
is suspected or there is a delay of more than several hours in collecting the specimens.
Antemortem (DUI) kits bear an expiration date which is intended to relate to the vacuum within the blood collection tubes. Use of expired tubes will not
invalidate findings determined with these specimens; however, vacuum within the tubes may be reduced, which may reduce the volume of specimen collected and,
accordingly, limit the scope of analyses which may be conducted. It is recommended that expired tubes be replaced with similar tubes from hospital stock.
Kits are so marked.
Antemortem (DUI) Kit
Antemortem (DUI) kit contents
Properly packaged antemortem
Properly sealed blood
Low volume specimen
Properly sealed kit
A postmortem kit is intended for Coroners for collection of specimens from deceased subjects. This kit contains two 30-mL
screw-cap containers, one for blood and the other for urine. The kit also contains a collection needle and syringe and seals.
Both containers should be completely filled with the respective specimens for a complete scope of analyses.
Postmortem kit contents
Postmortem kit needle and syringe
Postmortem kit containers
Properly sealed postmortem specimens
By submitting specimens, the investigating agency
acknowledges that the Toxicology Discipline will conduct examinations at its
discretion pursuant to current policies, procedures and capabilities and the
nature of the case as determined from information provided by the submitter.
The investigating agency further acknowledges that specimen volume, condition
and relevance may limit the number or types of examinations which may be
conducted and that whereas the Toxicology Discipline and the Department will
exercise all due diligence to preserve submitted materials, such are biological
in nature and, therefore, perishable.
Toxicological Analysis Request Form
The Alabama Department of Forensic Sciences Toxicology
Discipline operates in the Birmingham/Hoover Regional Laboratory.
Alabama Department of Forensic Sciences
Toxicology Section Birmingham/Hoover Regional Laboratory
2026 Valleydale Road
Hoover, AL 35244-2095
Tel (205) 982-9292
Fax (205) 403-2025
Section Chief: Jason S. Hudson, Ph.D
Toxicology Discipline Chief:
Curt E. Harper, Ph.D.
For more information on Forensic Toxicology, please click on the links below.
Academy of Forensic Sciences
Society of Forensic Toxicologists
National Library of Medicine PubMed Search Engine
Journal of Analytical Toxicology
Journal of Forensic Sciences
Forensic Science International
American Board of Forensic Toxicology
Forensic Toxicologist Certification Board