BACKGROUND: 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has a long half-life of 5-10 years in human beings as a result of its high lipophilicity, and little or no metabolism. We monitored TCDD, its form, distribution, and elimination in Victor Yushchenko after he presented with severe poisoning. METHODS: In late December, 2004, a patient presented with TCDD poisoning; the levels in his blood serum (108000 pg/g lipid weight) were more than 50 000-fold greater than those in the general population. We identified TCDD and its metabolites, and monitored their levels for 3 years using gas chromatography and high-resolution mass spectrometry in samples of blood serum, adipose tissue, faeces, skin, urine, and sweat, after they were extracted and cleaned with different organic solvents. FINDINGS: The amount of unmodified TCDD in the samples that were analysed accounted for about 60% of TCDD eliminated from the body during the same period. Two TCDD metabolites-2,3,7-trichloro-8-hydroxydibenzo-p-dioxin and 1,3,7,8-tetrachloro-2-hydroxydibenzo-p-dioxin-were identified in the faeces, blood serum, and urine. The faeces contained the highest concentration of TCDD metabolites, and were the main route of elimination. Altogether, the different routes of elimination of TCDD and its metabolites accounted for 98% of the loss of the toxin from the body. The half-life of TCDD in our patient was 15.4 months. INTERPRETATION: This case of poisoning with TCDD suggests that the design of methods for routine assessment of TCDD metabolites in human beings should be a main aim of TCDD research in the metabolomic era. FUNDING: University of Geneva Dermatology Fund, and Swiss Centre for Applied Human Toxicology.
Comment In: Lancet. 2009 Oct 3;374(9696):1131-219660808
With increasing age, diseases affecting the cognitive functions are more frequent. These diseases may increase the risk for fatal car crashes. We analyzed the frequency of neuropathological alterations characteristic of Alzheimer's disease (i.e. neuritic and diffuse plaques, and neurofibrillary tangles) in two association areas of the brain, parietal and frontal cerebral cortex, from 98 fatally injured aged drivers. In the age groups of 65-75 and over 75 years of age, 50% and 72% of the drivers, respectively, had neuritic plaques in either parietal and/or frontal cortex. In 14% of all killed drivers the number of neuritic plaques reached the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) age-related histologic score C, which indicates the diagnosis of Alzheimer's disease (AD), and an additional 33% had score B, which suggests the diagnosis of AD. Neuropathological AD changes were most common in the brains of drivers killed in single vehicle crashes, followed by multivehicle crashes at intersections and least common in multivehicle crashes elsewhere, but the differences did not reach statistical significance. In a great majority (80-85%) of cases the killed aged driver was the guilty party of the crash. The results imply, that incipient AD may contribute to fatal crashes of aged drivers, and therefore the forensic autopsy of these victims should include neuropathological examination.
The authors discuss the problem of selective derivation of the genetic material of spermatozoa for molecular genetic identification from mixed biological traces containing sperm on material evidence. Possible methods of improving the efficacy of differential lysis of cells present in mixed traces are analyzed. Effects of some routinely used extractants on biological substrata, most often contaminating the sperm in expert material, have been studied, and conditions for their most complete elimination from objects of investigation optimized.
The authors analyze in brief the forensic medical expert conclusions from various regions of Russia in which the experts assessed the position of subjects inside a car during accidents. Analysis showed a low level of the expert evaluations carried out because the method of comprehensive medical and technological expert evaluation was not resorted to. The authors present the fundamentals of the method, describe the stages of expert investigations, and enumerate the problems which are to be solved together by forensic physicians and experts in technology. They emphasize the necessity of using this method, which permits the experts make a better based conclusion with due consideration for complex multifactorial conditions of an accident.
Statistics are presented on the incidence of blood groups of 6 systems in the population of the Udmurt Republic. The data are compared with the results of similar surveys in other regions of the Russian Federation.
Contamination from methyl ethyl ketone and methanol utilized in a new technique to visualize fingerprints on human skin was detected postmortem in blood and vitreous humor by toxicological analysis. Two cases which represent the first field trials of the fingerprinting technique in Canada are presented. Details of the toxicological analyses and the nature of the contamination are discussed.
The placement of cadavers in shallow, clandestine graves may alter the microbial and geochemical composition of the underlying and adjacent soils. Using amplicon length heterogeneity-PCR (LH-PCR) the microbial community changes in these soils can be assessed. In this investigation, nine different grave sites were examined over a period of 16weeks. The results indicated that measurable changes occurred in the soil bacterial community during the decomposition process. In this study, amplicons corresponding to anaerobic bacteria, not indigenous to the soil, were shown to produce differences between grave sites and control soils. Among the bacteria linked to these amplicons are those that are most often part of the commensal flora of the intestines, mouth and skin. In addition, over the 16week sampling interval, the level of indicator organisms (i.e., nitrogen fixing bacteria) dropped as the body decomposed and after four weeks of environmental exposure they began to increase again; thus differences in the abundance of nitrogen fixing bacteria were also found to contribute to the variation between controls and grave soils. These results were verified using primers that specifically targeted the nifH gene coding for nitrogenase reductase. LH-PCR provides a fast, robust and reproducible method to measure microbial changes in soil and could be used to determine potential cadaveric contact in a given area. The results obtained with this method could ultimately provide leads to investigators in criminal or missing person scenarios and allow for further analysis using human specific DNA assays to establish the identity of the buried body.
The retrieval of bacteria from the lungs postmortem was examined in a population of alcoholics who had a medico-legal autopsy performed. The results were compared with non-alcoholic controls. Pneumococci were found more frequently in alcoholics, but in general there were no major differences. Proteus mirabilis was detected in three out of five alcoholics with unascertainable cause of death. It is speculated whether this species may cause septicaemia in some alcoholics due to abnormal splanchnicus circulation.
This study was prompted by a recent judgment in the Royal Courts of Justice (Gregory v. Director of Public Prosecutions, 2002) in a case of driving a motor vehicle after consuming too much alcohol (Road Traffic Act 1988). An expert witness for the defence alleged that a deficient volume of blood in the tube sent for analysis meant an excess amount of sodium fluoride (NaF) preservative, which would increase the concentration of ethanol, determined by headspace gas chromatography (HS-GC), owing to a salting-out effect. The prosecution did not produce expert evidence to rebut this argument and the drunk driving suspect was acquitted. A small volume of blood and excess sodium fluoride might have increased the concentration of ethanol in the air-space in the tube sent for analysis but this does not mean that the result of the HS-GC analysis would be higher. This follows because prior to analysis an aliquot of blood is removed and diluted (approximately 10 times) with n-propanol as the internal standard. The dilution lowers the concentration of NaF in the blood and for quantitative analysis the ratio of the ethanol to n-propanol response is measured. The use of a ratio also helps to compensate for any salting-out effect of ethanol. Our experiments showed that a deficient volume of blood and excess NaF actually lowered the concentration of ethanol by 2-3% compared with heparinised blood. Seemingly, n-propanol (n-PrOH) a 3-carbon straight chain alcohol is salted out slightly more effectively than the 2-carbon ethanol (EtOH) causing a lower peak area ratio (EtOH/n-PrOH) and a lower apparent concentration of ethanol. In a separate study, we showed that the concentration of ethanol was lowered even more when a 4-carbon alcohol (t-butanol) was used as the internal standard.