L7 - Forensic toxicology cases MLS 2023.handout.pdf

Can be rare, unusual and may take months or years to resolve! Graham R. Jones, Ph.D. Former Chief Toxicologist Office of the Chief Medical Examiner and Clinical Professor, Faculty of Medicine and Dentistry [email protected] CASE #1: CHLOROFORM HOMICIDE Wife killed with chloroform by husband in...

Can be rare, unusual and may take months or years to resolve! Graham R. Jones, Ph.D. Former Chief Toxicologist Office of the Chief Medical Examiner and Clinical Professor, Faculty of Medicine and Dentistry [email protected] CASE #1: CHLOROFORM HOMICIDE Wife killed with chloroform by husband in the guise of a ‘robbery gone wrong’ Police found:  goods neatly stacked by open front door (little value)  husband in basement with hands and feet loosely bound; mask loosely taped over mouth  wife upstairs (dead), with mask taped over mouth and signs of struggle, broken dentures, facial abrasions. Initial Toxicology:  Headspace GC/FID used for initial identification of chloroform to assist police with their investigation; relatively easy Husband says:  he was woken up by noise  went downstairs to investigate  was attacked from behind and a solvent placed over his face  he woke up to find his hands and feet bound with tape  he later managed to phone 911 and alert police  Wife had injuries showed signs of a struggle  Husband “unmarked”  911 Phone call to police  Voice recognition expert  The wife was pregnant  Husband took out insurance on wife  Husband had a girlfriend “on the side” Wife: Chloroform in blood: 105 mg/L (85-124 mg/L) Husband: Chloroform in blood: 0.16 mg/L BUT, 6 hours after the event! Reference ranges:  Homicide 10-49 mg/L (mean 33; n=5)  Suicide 17-43 mg/L (mean 32; n=5)  Anesthesia 50-150 mg/L (depends on depth/stage)  Preliminary hearing,  Jury trial and conviction,  Appeal, re-trial and re-conviction.  Life sentence with no possibility of parole  Presumptive identification of the chloroform occurred the same day the body was found  Police investigation took several months  Source of chloroform was never determined, but the accused was a microbiologist and worked in a laboratory  Although chloroform was used as an anesthetic in mainstream medicine for years, as for many medicines, it is not just the dose but the MANNER in which it is administered can be critical  The accused didn’t realize that chloroform or any volatile anesthetic agent takes time to build up a concentration high enough to render someone unconscious  In the meantime, the victim will fight and resist the assault  Doctor Convicted of First-Degree Murder : Crime: Samson Dubria used chloroform to subdue and rape a companion, who died of an overdose of the substance. - Los Angeles Times (latimes.com)  Medical resident Dr. Samson Dubria told police that his ‘girlfriend’ mysteriously died after they had consensual sex at the motel in Carlsbad, CA.  Toxicological tests later detected a lethal amount of chloroform in her body, leading to the charges against Dubria.  When police asked Dubria how the drug might have gotten in her body, he suggested that she might have inhaled it when they drove past a truck hauling the chemical on the freeway(!!!).  The defense later suggested that she might have administered chloroform to herself to relieve headache pain. However, experts testified that it is almost impossible to selfadminister an overdose of chloroform without leaving evidence behind.  Dubria admitted he was the only one there with her and. Because the couple had just engaged in sex, Deputy District Attorney Tim Casserly contended the defendant’s motive for administering the chloroform was to render his companion unable to resist his advances.  The victim’s friends and family testified that she was not romantically interested in Dubria and would not have consented to sex with him because she was in love with someone else. Young wife dies from the homicidal administration of digitoxin – a difficult analytical case CASE HISTORY…  Husband bought lunch for the family from Taco Bell  About 1 hour after eating a burrito the wife started to feel unwell  severe nausea and vomiting later developed  Wife taken to hospital 3 h after eating the taco  Condition deteriorated and she developed supraventricular tachycardia and heart block and was eventually admitted to the CCU  She died ~10 h after admission ALBERTA OCME INVESTIGATION  Autopsy: no “anatomic” cause of death  Microbiological studies essentially negative  Result of Dynacare antemortem serum ‘digoxin’ of >30 ug/l forwarded to Medical Examiner (OCME) by the clinical lab  OCME Toxicology: antemortem serum ‘digoxin’ 2.5 ug/l  OCME and clinical ‘digoxin’ testing repeated  similar results as the first tests  Police informed that the death was suspicious NATURAL PRODUCT CARDIOTOXIC STEROIDS Bufo (Toad) Urginea (Squill) Strophanthus Oleander Digitalis lanata D. purpurea WHERE DO WE START?  Problem: to specifically identify and quantitate the toxin  Immunoassay results were useful, but not definitive  Problem: GC and GC/MS cannot be applied  Digoxin and similar glycosides break down in GC injection port  LC/MS useful, but not available initially  Solution: try to use different immunoassays to try to identify or rule out cardiac glycosides  Outcome: likely digitoxin; possibility of ouabain NEXT?  Find someone who:  A. Has a LC/MS  B. Has some experience with postmortem specimens  C. IDEALLY has worked with cardiac glycosides  D. Is willing to look at a postmortem blood sample  Montreal Justice laboratory  LC/MS (trap): initial identification of digitoxin, but quantitation not reliable  Alberta Justice, OCME  Bought a new LC/MS and developed a quantitative method for digitoxin LC/MS IDENTIFICATION Full Scan of 500 Cal Digitoxin Peak Full Scan of Case Digitoxin Peak LC/MS – QUANTITATIVE Specimen Time A/m Plasma 1735h A/m Serum 1735h A/m Serum 2345h A/m Serum 0045h A/m Serum 0310h A/m Serum 0310h A/m Serum 0310h A/m Serum 0310h Postmortem Blood Postmortem Blood Vitreous Serum therapeutic: 10 - 35 ng/ml Digitoxin (LC/MS) ng/ml 395 293 171 RIA 384 369 307 299 279 246 239 256 227 283 3 OUTCOME: HOMICIDAL DIGITOXIN POISONING  Identification and quantitation confirmed by LC/MS  Victim likely poisoned with pure digitoxin (difficult to disguise plant material)  Victim did not have heart disease and was not prescribed digitoxin  No one else in household prescribed digitoxin  Death determined to be a homicide!  Digoxin, digitoxin and other cardiac glycosides cannot be      detected by most routine drug screening methods (unless targeted by LC/TOF or LC/MS) Cardiac glycosides cannot be detected or measured by GCbased methods because they are not volatile enough – they undergo thermal breakdown before they transform into the gas phase We got “lucky” in this case because an astute cardiac resident thought the symptoms were similar to “digoxin” toxicity and ordered a “digoxin” test (unfortunately he was too late) Good communication meant that the clinical chemist at Dynacare phoned the result to the forensic toxicologist at the OCME The source of the digitoxin was never identified Despite strong suspicion that the husband was the poisoner, he was never charged by police  March 1998  Confesses on NBC Dateline to murdering 50 patients  Interviewed by Glendale PD; repeats confession  April 1998  Retracts confession on ABC 20/20 and Extra  “Suicidal”, but didn’t have the courage to kill himself  Pancuronium Br (Pavulon)  Succinylcholine (Anectine)  Ventilator Settings (changing them)  Spring/Summer 1999 on…  Medical review of 50 deaths by a anesthesiologist and cardiologist  Focused on 20 suspicious deaths  Exhumations of 20 bodies  Review of +++ medical records for drugs prescribed  Toxicology testing commences  Find lab…Lawrence Livermore National Laboratory (Livermore, CA)  Start with pancuronium  Develop extraction (SPE) method  Develop LC-MS/MS method  Analyze 20 cases x 10+ specimens per case  Embalmed and partially decomposing tissues  Presence of pancuronium proves a patient received it  But…was it from Saldivar or from previous surgery?  Needed careful review off the medical records for months prior  What is the half-life:  In blood (not an issue – no blood available)  In tissues…little known…  Pancuronium and/or unique metabolites were found in five or six patients who were not prescribed the drug  It was decided not to pursue succinylcholine  Too unstable; breakdown products are naturally occurring January 2001  Re-arrested by GPD  New confession - up to 100- 200 deaths?  Charged in 6 deaths where pancuronium and/or metabolites were detected  Saldivar arraigned: pleads not guilty  The “homicides” may never have been discovered had Saldivar not “confessed” – even though he retracted his confession  After retraction of the confession, police were forced to launch a detailed medical and forensic investigation aided by an anesthetist, cardiologist to review over 50 medical files in detail where Saldivar was “on duty”  Forensic toxicologist also retained by Glendale police (Jones)  Review was to determine most likely cases where the individuals may have died very suddenly (although all victims were elderly and most in very poor health)  20 cases selected and all were exhumed. All had been embalmed and buried years before  Examination of decomposed tissue for pancuronium by LC- MS/MS (stable); could not realistically test for succinylcholine (unstable) Husband accused of killing his wife with alcohol, alprazolam and cadmium  37 year old woman found not breathing by her husband at about 7.30 am (staying at a resort)  EMS did CPR, but wife was DOA at local hospital  History of alcohol and alprazolam abuse  Autopsy: negative except for sarcoidosis  Extensive toxicology ordered Ethanol Blood Urine 120 mg% 126 mg% Alprazolam Blood 54.6 ug/l Bupropion Blood 88 ug/l Cadmium Blood 60 ug/l Lab states “normal” blood cadmium <5 ug/l. Exposed 5 ug/l. Toxic >10 ug/l. Cadmium Concentrations (ug/l or ug/kg) Bottle 1 150 (powder) Bottle 2 60 (liquid) Bottle 3 <0.5 (liquid) Bottle 4 <0.5 (liquid) Bottle 5 2.1 (liquid) Bottle 6 <0.5 (liquid) Police comments: “three of six specimens tested positive for cadmium” Alberta 'Reference' Values for Blood Cd ( ug/l) Cadmium Sex Age COD 217 M 77 Acute MI 65 M 91 Coronary AS 6 F 64 Coronary AS 92 M 67 Acute MI 1 F 54 OccCorH 2 M 63 Coronary AS 69 M 33 ? <0.2 Blank tube 'Normal' Cadmium Concentrations ug/l or ug/kg Blood Liver Kidney (RC) Non Smokers 0.9 1000 13000 Smokers 1.5 1300 24000  Jones eventually retained by Orlando Public Defender and subpoenaed to testify at trial  Jones opined that the cadmium was likely “natural” and not likely to be the cause of death  Cadmium blood concentrations increase after death due to postmortem release and redistribution  Meanwhile the Florida pathologist changed his opinion and dropped “cadmium poisoning” from the COD and changed the manner to “accidental”  Prosecution case collapses and charges withdrawn; accused freed  Don’t assume that you can assign “clinical” reference ranges for serum or plasma to postmortem blood  Refer to the medical and forensic literature – don’t just rely on so-called reference ranges  Not just drugs undergo postmortem redistribution – it can apply to metals and chemicals as well  Look at the results in the context of the case and circumstances. Do they make sense?