3,5-Dimethoxyphenol identification from urine by GC-MS after a lethal intoxication with Taxus baccata: A case report

Abstract

Taxus baccata, also known as English or European yew, is an evergreen conifer shrub or tree that is traditionally used in ornamental landscaping, woodwork and pharmaceutical purposes. The toxic nature of the yew plant has been known for more than 2000 years. All parts of the plant, except for the red pulp of its berries, contain taxine alkaloids. Minimum lethal doses are reported in the range of 0.6-1.3 g of leaf/kg body weight, which means that for a 70-kg adult this vary between 42 and 91 g of yew leaf. Intoxication is known to be resistant to standard treatments with no effective antidote. The aim of this study was the confirmation of Taxus poisoning by 3,5-dimethoxyphenol determination. A case of an intentional fatal poisoning of a 39-year-old man is presented, hypothesized by the forensic autopsy and confirmed by application of gas chromatography-mass spectrometry. Postmortem urine sample was analysed, after liquid-liquid extraction with dichloromethane from acidic and basic environment. The autopsy has not revealed any significant traumatic injuries or specific pathological lesions. Suggestive content was found in the oral cavity, esophagus and stomach, containing partially digested food mixed with fragmented needle-shaped, green leaves. During toxicological analysis, 3,5-dimethoxyphenol (3,5-DMP), the aglycone of taxicatine metabolite, considered as a marker of Taxus poisoning, was identified in the urine using the NIST spectra library database. Taxine alkaloids are the active constituents of Taxus sp. that cause cardiotoxicity. This occurs via the dose-dependent blockade of sodium and calcium channels in cardiac myocytes, leading to atrioventricular block, evidenced by prolonged PR and QRS intervals on ECG. The clinical severity is dependent on quantity, type an route of exposure, clinical signs usually occur within 3-4 h after ingestion. Yew tree poisoning has a high mortality rate, but remains a rare occurrence, with only a few case reports in literature. Analysis of taxine alkaloids can be used to confirm the diagnosis.