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In December 2002, approximately 250 lbs. of ground beef was adulterated with nicotine sulfate by a supermarket employee and subsequently sold to the public. Soon afterward, reports of illness associated with ground beef purchased at a single store were identified. Authorities suspected the ground beef was tainted with Black Leaf 40, a banned pesticide containing approximately 40% nicotine as nicotine sulfate. Ground beef submitted to our laboratory was analyzed in concert by high performance liquid chromatography-ultraviolet detection (HPLC-UV), gas chromatography-mass spectrometry (GC-MS), and high performance anion exchange chromatography with suppressed conductivity detection. GC-MS was used to identify the samples that contained nicotine. The nicotine was confirmed and quantitated by HPLC-UV. The sulfate was identified and quantitated by high performance anion exchange chromatography with suppressed conductivity detection. Our analysis revealed that the raw tainted beef contained about 350 mg/kg nicotine free base, a potentially lethal dose of nicotine per serving for an adult. Additionally, we found elevated sulfate levels in the samples that tested positive for nicotine, providing evidence that nicotine sulfate was the probable adulterant. 相似文献
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The death of Kaspar Hauser is described taking present medicolegal and criminological knowledge into account, the main question being whether the injury was self-inflicted, homicidal or suicidal. In spite of a critical retrospective analysis this question cannot be answered with sufficient certainty even from our modern perspective. It seems unlikely that the stab to the chest was inflicted exclusively for the purpose of self-damage, but both a suicidal stab and a homicidal act (assassination) cannot be definitely ruled out. 相似文献
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