A 20 year retrospective study of cyanide intoxication cases Brigitte
1,2* Desharnais ,
Pascal
1 Mireault ,
Cameron D.
2 Skinner
1Laboratoire
de sciences judiciaires et de médecine légale, Department of Toxicology, 1701 Parthenais St., Montréal, Québec, Canada, H2K 3S7 2Concordia University, Department of Chemistry & Biochemistry, 7141 Sherbrooke St. West, Montréal, Québec, Canada, H4B 1R6 *Correspondence :
[email protected]
Introduction Cyanide is a powerful chemical asphyxiant. It acts mostly through fixation to cytochrome C oxidase, the mitochondrial enzyme responsible for the last step in cell respiration, and to hemoglobin, the blood oxygen transporter. Cyanide intoxication is most often encountered in suicide or murder cases. These cases are rare in North America, most likely because access to cyanide is restricted. The majority of intoxications occur via ingestion of a cyanide salt (KCN or NaCN). The aim of this project was to compile toxicology results and autopsy findings from cyanide intoxication cases in the province of Quebec in order to complement data provided by the small number of cases reported in the literature.
Methods The pathology and toxicology information of cyanide intoxication cases, between 1995 and 2015, was retrieved and compiled. All gastric contents during that
time frame were screened for the presence of cyanide vapour using a pump with a Draeger-Tube filled with HgCl2 and methyl red that turned red in the presence of HCN. A colorimetric screening method, using a Conway cell and o-dinitrobenzene, was used for the screening of other matrices. Prior to 2011, cyanide in biological matrices was quantitated spectrophotometrically. Briefly, a diluted aliquot of the sample was acidified with tartaric acid to generate volatile HCN gas which was retained in a NiCl2 trap. Upon dilution, the NiCN4 complex was formed and measured spectrophotometry. Post2011, the quantification method was changed to a published headspace GC-MS method using 13C15N as an internal standard (ISO 17025 compliant).
morphine, venlafaxine, clonazepam and THC. The most common autopsy findings were heavy and congested lungs with edema, cherry-red blood and lividities and hyperaemia of the gastric mucosa (see Figure 1). A strong scent of bitter almond was also noted by the restricted number of pathologists and assistants with the ability to smell cyanide.
Discussion
Acknowledgements
Case specific data, including cyanide concentration, is shown in the Table below. Other xenobiotics detected in biological matrices included ethanol, codeine, acetaminophen, methotrimeprazine,
Funding was provided by the Natural Sciences and Engineering Research Council of Canada.
Figure 1: Hyperaemia of the gastric mucosa
Cyanide Concentration Case
1
Year
1999
Gender
M
Age
50
Cardiac Femoral Gastric Blood Blood Content (μg/mL) (μg/mL) (mg) 10
N/A
500
2
1999
M
72
18
3.5
34
3
2003
M
57
30
N/A
300
4
2007
M
77
21.0(1)
0.30(1)
1.00(1)
5
2008
M
58
127(1)
5
38
6
2010
M
33
90
7.50(1)
130
7
2011
M
32
2.41(1)
2.28(1)
4.00(1)
8
2011
9
2013
(1)Quantification
Solution: 160 mg/mL(1) M
by GC-MS
46
3.99(1)
4.60(1)
25.0(1)
Description of the events
Ex-chemist found dead in his parked car. A suicide letter was found at home saying he ingested KCN. Victim had prostate metastatic cancer and consumed a cyanide salt. Found dead in his appartment, head on his pillow with a suicide note stating he used cyanide. Found dead at home, a bottle of KCN near the body. A solution found had [CN-] = 18.3 μg/mL. Suicide with KCN, a letter was found on the scene. Found dead on a pedestrian trail, had been talking about suicide in the previous days. Found dead at home. Due to a severe illness in 2009, the victim had no legs and no arms. Assisted suicide was suspected. Plot to assassinate another person. Prisoner linked to the mafia found dead in his cell during the midnight round. Suspected drug user.
