Expert Article Library
Testing for Drugs in the Exhumed Body: Confounding Issues in Quality Control, Specificity & Reliability
By David M. Benjamin, PhD Email: firstname.lastname@example.org
LEARNING OBJECTIVES: After attending this presentation, the participant will understand: (1) the special problems encountered in analyzing biological samples obtained from embalmed/exhumed bodies, (2) the limitations of conventional immunoassay and chromatographic analytical "screening test" when applied to biological samples obtained from embalmed or exhumed bodies, and (3) the importance of confirmatory testing in providing scientifically reliable evidence.
Forensic toxicologists are frequently required to analyze biological specimens obtained from embalmed or exhumed bodies for the presence of drugs. Often, the first line of approach are rapid, inexpensive immunoassay procedures such as the enzyme-mediated immunoassay (EMIT) or the radio immuno assay (RIA), or chromatographic procedures such as Thin-Layer Chromatography (TLC), Gas-Liquid Chromatography (GLC), and High-Pressure Liquid Chromatography (HPLC). However, immunoassays and chromatographic procedures are not specific for a particular analyte molecule and cross-reactivity with chemically-related molecules can occur leading to false positive results. In order to confirm the presence of a substance determined to have been present in a screening procedure, the use of a confirmatory Mass Spectrometry (MS) test is generally recognized as the "Gold Standard". Usually, the analyte is isolated from the biological samples by acidic or basic extraction into an appropriate organic solvent, followed by separation from other biological and xenobiotic molecules by Gas Chromatography (GC). The purified analyte molecule is then directed into the MS for analysis based on the appearance of fragments of the parent molecule which are specific only for the substance under analysis.
The case of Commonwealth of Massachusetts v. Christina Martin is an example of how the unconfirmed results of analytical testing for LSD came under suspicion and resulted in the 1999 release of Ms. Christina Martin from prison, where she had been incarcerated since her November 13, 1992 jury conviction for first degree murder. Christina Martin was 35 years old, and lived with her 61 year old boyfriend Richard Alfredo, the decedent, her 14-year old daughter Teasha, and one other child. Mr. Alfredo had long-standing cardiac disease and had undergone cardiac bypass surgery years earlier. Based on Teasha's report that Mr. Alfredo had sexually abused her, Christina, the mother, promised her daughter that she would make him hurt for his misdeeds. Both then tried to purchase mescaline on the street, however, upon telling the local youths that they intended to kill the boyfriend, the youths sold them bogus drugs. Allegedly, the pair was ultimately successful in purchasing real mescaline, some of which Teasha ingested and "verified" as active. They then proceeded to prepare Jello containing the illicitly-obtained drugs and administered the Jello to the boyfriend. On January 21, 1990, ten or so minutes after ingesting the "poisoned" Jello, Richard Alfredo suffered a heart attack and died. In view of the decedent's history of heart disease, the manner of death was believed to have been natural; however based on Teasha's disclosures to her friends, the previously-embalmed body was exhumed 31 days later for forensic analyses. A large amount of ground water had gotten into the casket, and a video-tape of the autopsy showed the medical examiner literally "ringing out" the body organs as he removed them from the body cavity.
Using the Roche Abuscreen RIA screening test, the Crime Laboratory of the Commonwealth of Massachusetts detected the presence of LSD in specimens of blood, urine, CSF, intestinal contents, vitreous fluid, and chest fluid; however, confirmatory testing with GC-MS was negative. In order to obtain a confirmed presence of LSD, the Commonwealth forwarded samples obtained from the coffin to National Medical Services for further testing. Once again, using RIA and chromatographic techniques, LSD was reported positive in cavity fluid, urine, arterial fluid and intestinal fluid. Blood samples also showed the presence of diphenhydramine (Benadryl), an antihistamine Mr. Alfredo was taking for what he believed to be a cold or flu. At trial, Dr. Sagall, a local cardiologist with no training in toxicology or experience in treating LSD toxicity, and who, relying solely on "several textbooks" he read, testified that LSD could increase the heart rate, and that such tachycardia caused a heart attack in Mr. Alfredo due to his long-standing cardiac condition. However, Dr. Sagall neglected to mention that Goodman and Gilman's textbook, upon which he relied, also stated that "In man, deaths attributable to direct effects of LSD are unknown", and that diphenhydramine is a powerful anticholinergic agent even more capable of producing a tachycardia than LSD. Following a hearing for a new trial at which this author testified, and an appeal by the Commonwealth to the Supreme Judicial Court of Massachusetts, a new trial was granted. Ultimately, the Commonwealth reduced the charges to Manslaughter and time served and Ms. Martin was released.