Kanako Watanabe

Simultaneous analysis of α-amanitin, β-amanitin, and phalloidin in toxic mushrooms by liquid chromatography coupled to time-of-flight mass spectrometry

An entire procedure for simultaneous analysis of α-amanitin, β-amanitin, and phalloidin in mushrooms by liquid chromatography (LC) electrospray ionization (ESI) time-of-flight (TOF) mass spectrometry (MS) has been optimized and established. We used a hydrophilic interaction column TSK-gel Amide-80 3 μm for LC separation, which enabled the simultaneous detection of the three toxins and internal standard microcystin RR. After homogenizing mushroom debris with methanol acidified with trifluoroacetic acid, the extract solution was subjected to solid-phase extraction with an Oasis HLB cartridge. The eluate was applied to the LC-ESI-TOF MS instrument. The calibration curves for the three toxins showed good linearity over the range of 100–1000 ng/g. The detection limits (signal-to-noise ratio = 3) for α-amanitin, β-amanitin, and phalloidin were about 30, 30, and 10 ng/g, respectively. The recovery rates of the three toxins at 100, 500, and 1000 ng/g were in the range of 53.1%–69.6%. The accuracy and precision (both intraday and interday) at 100, 500, and 1000 ng/g ranged from 87.9% to 117% and from 3.58% to 15.6%, respectively. Using the present method, the concentrations of the three toxins in the caps, stems, and roots of the toxic mushroom Amanita virosa were measured. The described method should be applicable to measurement of the Amanita toxins in human specimens, such as urine and blood of poisoned subjects.

Simple extraction of phencyclidine from human body fluids by headspace solid-phase microextraction (SPME)

SummaryPhencyclidine (PCP) was found to be extractable by headspace solid-phase microextraction (SPME) from human whole blood and urine. Sample solutions were heated at 90°C in the presence of NaOH and K2CO3, and an SPME fiber was exposed in the headspace of a vial for 30 min. Immediately after withdrawal of the fiber, it was analyzed by gas chromatography with surface ionization detection (GC-SID). Recoveries of PCP were approximately 9.3–10.8% and 39.8–47.8% for whole blood and urine samples, respectively. The calibration curve for PCP showed good linearity in the range 2.5–100 ng mL−1 whole blood and 0.5–100 ng mL−1 urine. The detection limits were approximately 1.0 ng mL−1 for whole blood and 0.25 ng mL−1 for urine.

Postmortem distribution of α-pyrrolidinobutiophenone in body fluids and solid tissues of a human cadaver

We experienced an autopsy case of a 21-year-old male Caucasian, in which the direct cause of his death was judged as subarachnoid hemorrhage. There was cerebral arteriovenous malformation, which seemed related to the subarachnoid hemorrhage. The postmortem interval was estimated to be about 2days. By our drug screening test using gas chromatography-mass spectrometry, we could identify α-pyrrolidinobutiophenone (α-PBP) in his urine specimen, which led us to investigate the postmortem distribution of α-PBP in this deceased. The specimens dealt with were right heart blood, left heart blood, femoral vein blood, cerebrospinal fluid, urine, stomach contents and five solid tissues. The extraction of α-PBP and α-pyrrolidinovalerophenone (α-PVP, internal standard) was performed by a modified QuEChERS (quick, easy, cheap, effective, rugged and safe) method, followed by the analysis by liquid chromatography-tandem mass spectrometry. Because this study included various kinds of human matrices, we used the standard addition method to overcome the matrix effects. The highest concentration was found in urine, followed by stomach contents, the kidney, lung, spleen, pancreas and liver. The blood concentrations were about halves of those of the solid tissues. The high concentrations of α-PBP in urine and the kidney suggest that the drug tends to be rapidly excreted into urine via the kidney after its absorption into the blood stream. The urine specimen is of the best choice for analysis. This is the first report describing the postmortem distribution of α-PBP in a human to our knowledge.

Mushroom toxins: a forensic toxicological review

Mushrooms are ubiquitous in the world. Amateur hunters harvest mushrooms growing in forests to enjoy eating them as seasonal delicacies, and occasionally they cause poisonings and even deaths. In this review, mushroom toxins are tabulated according to mushroom species, symptoms, toxicities and analytical methods on the basis of references. Second, because we constructed a method for analysis of amatoxins, the most virulent mushroom toxins, by liquid chromatography-time-of-flight-mass spectrometry, we introduce it for use in forensic toxicology. Third, an extensive poisoning incident after consumption of the usually edible mushroom Pleurocybella porrigens took place in nine prefectures in Japan from September to December 2004, resulting in 59 poisoned people including 19 deaths; this incident is briefly described and discussed in relation to its causative toxin(s). Finally, we present the chemical structures of new toxins purified from the highly toxic mushrooms Podostroma cornu-damae and Russula subnigricans; their structures were very unique, and the toxicities were comparable to those of amatoxins. From the forensic toxicological point of view, reports on sophisticated methodology for analyses of mushroom toxins seem to be too scant even for the well-known toxins. Hereafter, a number of toxic mushrooms and their new toxins are expected to be disclosed, especially because of environmental changes such as the global warming phenomenon.

2. An Unusual Death due to the Impalement of a Gear Stick into the Brain Stem through the Nasal Cavity

A 59-year-old male was driving a car on the road and was involved in a traffic accident, colliding with a tanker and a big lorry. When an ambulance arrived at the scene, he was in a state of cardiopulmonary arrest and was bleeding profusely from his right nostril. He was confirmed dead at hospital. The autopsy showed a laceration of the right upper lip extending to the right nostril. In the basal skull there was a notable perforation at the ethmoid bone together with the central part of the sphenoid bone including the sella turcica. In accordance with the basal skull bone fractures, there were pronounced contusion injuries at the brain stem and a contusion injury was also observed in the right part of the cerebellum. After careful investigation of a causative stick-like item that was present inside the car, it was concluded that a severe movement of the mans body, as a result of the traffic collision, caused the gear stick which was fixed to the steering wheel to become impaled in the mans right nostril. The gear stick passed through the nasal cavity and into the basal skull bones, resulting in fatal brain stem injuries.

Determination of solvent thinner components in human body fluids by capillary gas chromatography with trapping at low oven temperature for headspace samples

A simple and sensitive method is presented for determination of solvent thinner components in human body fluids by capillary gas chromatography (GC) with a low oven temperature for trapping headspace vapor components. After heating a blood or urine sample containing ethyl acetate, benzene, butan-1-ol, toluene, butyl acetate, isoamyl acetate and ethylbenzene (internal standard) in a 7.5 ml vial at 90 degrees C for 30 min, 5 ml of headspace vapor were drawn into a glass syringe. All vapor was introduced through an injection port in the splitless mode into a DB-624 medium-bore capillary column at a 5 degrees C oven temperature for trapping the volatile compounds, and the oven temperature was programmed up to 110 degrees C for their detection by GC. These conditions gave sharp peaks, a good separation of each peak and low background noise for both whole blood and urine samples. As much as 3.58-55.1 and 3.52-57.9% of the six compounds, which had been added to vials, could be introduced to the GC instrument for whole blood and urine, respectively. The intra-day RSD values in terms of the introduction rate (net recovery) of the six compounds in whole blood and urine samples were < or = 8.1%. The calibration curves showed linearity in the range 0.78-400 ng per 0.5 ml whole blood or urine. The detection limits were 0.5-5 ng per 0.5 ml. The data on toluene in post mortem blood in an actual case are also presented.

Identification and quantification of metabolites of AB-CHMINACA in a urine specimen of an abuser

We experienced an autopsy case in which the cause of death was judged as poisoning by multiple new psychoactive substances, including AB-CHMINACA, 5-fluoro-AMB and diphenidine [Forensic Toxicol. 33 (2015): 45-53]. Although unchanged AB-CHMINACA could be detected from 8 solid tissues, it could neither be detected from blood nor urine specimens. In this article, we obtained eight kinds of reference standards of AB-CHMINACA metabolites from a commercial source. The AB-CHMINACA metabolites from the urine specimen of the abuser were extracted by a modified QuEChERS method and analyzed by liquid chromatography-tandem mass spectrometry before and after hydrolysis with β-glucuronidase. Among the eight AB-CHMINACA metabolites tested, only 2 metabolites could be identified in the urine specimen of the deceased. After hydrolysis with β-glucuronidase, the concentrations of the two metabolites were not increased, suggesting that the metabolites were not in the conjugated forms. The metabolites detected were 4-hydroxycyclohexylmethyl AB-CHMINACA (M1), followed by N-[[1-(cyclohexylmethyl)-1H-indazol-3-yl]carbonyl]-l-valine (M3). Their concentrations were 52.8 ± 3.44 and 41.3 ± 5.04 ng/ml (n=10) for M1 and M3, respectively. Although there is one preceding report showing the estimations of metabolism of AB-CHMINACA without reference standards, this is the first report dealing with exact identification using reference standards, and quantification of M1 and M3 in an authentic urine specimen.

Simultaneous determination of cocaethylene and cocaine in blood by gas chromatography with surface ionization detection

SummaryCocaethylene together with cocaine spiked in human whole blood has been found measurable at high sensitivities by capillary gas chromatography with surface ionization detection. The drugs could be rapidly extracted by Sep-Pak C18 cartridges with recovery of more than 60%. The calibration curves for both cocaethylene and cocaine using cocapropylene as internal standard were linear in the range 50–300 pmol mL−1 of whole blood. The detection limits of cocaethylene and cocaine were 5–10 pmol mL−1 (0.1–0.2 pmol on column if recovery is 100%). Cocaethylene could be determined for whole blood obtained from rats (ca. 200 g body wt.), which had received subcutaneous injection of 10 mg cocaine hydrochloride and 2.0 mL of 30% (v/v) ethanol 3 h before sampling; the mean levels of cocaethylene and cocaine were 101 and 1230 pmol mL−1, respectively.

Quantitation of postmortem profenofos levels

CASE REPORT An 88-year-old woman was found dead, and suicidal ingestion of profenofos, an organophosphate pesticide, was suspected. METHOD Gas chromatography-nitrogen phosphorus detection was employed for quantitation of profenofos after its identification by gas chromatography/mass spectrometry. RESULTS The levels of profenofos in whole blood, urine, and gastric contents were 1200 ng, 350 ng, and 3.35 mg/mL, respectively.

Sensitive determination of arsenite and arsenate in plasma by electrospray ionization tandem mass spectrometry after chelate formation

Inorganic arsenite (As3+) and arsenate (As5+) are well-known poisons, and the toxicity of As3+ is about ten times that of As5+. In this study, a simple, rapid, and sensitive method was developed for As3+ in plasma using electrospray ionization (ESI) tandem mass spectrometry (MS-MS). After washing plasma with trichloroethylene (TCE), As3+ in the aqueous layer was reacted with pyrrolidinedithiocarbamate (PDC, C4H8NCSS-), and the produced As(PDC)3 was extracted with methyl isobutyl ketone (MIBK); a 1-µl aliquot of the MIBK layer containing As(PDC)3 was introduced into the MS-MS instrument in the direct-flow injection mode. Other arsenic compounds such as As5+, monomethyl arsonic acid, dimethyl arsinic acid, arsenobetaine, arsenocholine, and tetramethyl arsonium did not produce As(PDC)3. Therefore, without liquid chromatographic separation, As3+ alone could be detected after washing with TCE followed by solvent extraction of As(PDC)3 with MIBK. Thus, inorganic As5+ was reduced to As3+ with thiosulfate, and then the total inorganic As was quantifi ed as As3+; As5+could be calculated by subtracting As3+from the total inorganic As. The MS-MS quantification was performed by selected reaction monitoring using a peak at m/z 114 of a product ion (C4H8NCS)+ formed by collision-induced dissociation from the precursor ion As(PDC)2+ at m/z 367. The mass spectral identification on MS-MS spectrum was possible even at 1 ng As3+/ml plasma. The calibration curve for As3+ showed linearity from 0.5 to 100 ng/ml plasma. The limits of detection by selected reaction monitoring were 0.3 ng/ml in water and 0.2 ng/ml in plasma. The analysis could be completed in less than 15 min, because chromatographic separation was not necessary before the MS-MS detection.