why do toxicology reports take so long


Lab tests to determine what killed singer Amy Winehouse will take two to four weeks, according to the Scotland Yard. Unlike television crime shows where results are instant, standard toxicology tests can require several steps, taking up to several weeks. An autopsy completed Monday afternoon was inconclusive and investigators will need the toxicology results to determine the singer s cause of death,
Toxicology tests are used to determine whether and how much legal or illegal drugs a person has taken. While it s unclear what caused Winehouse s death, her erratic behavior and drug problems were public after she reached musical stardom in 2007. In post-mortem toxicology screenings, blood is drawn from various areas of the deceased person s body. This initial test indicates what type of drugs, such as opiates or amphetamines, might be present. The secondary part is where it becomes complicated. If the screening test indicates the person may have had opiates in his or her body, further tests are required to figure out what kind of opiates and in what amount. You confirm the preliminary test, said Douglas Rohde, supervisor of chemistry and toxicology at the Lake County Crime Lab in Ohio. You confirm that drug is actually there. There s not one test as seen in CSI. There s no quick test that gives you a positive identification and confirmation.


The confirmatory tests can take days or weeks, if they have to be repeated. To confirm that a person had a type of drug in his or her body, the drug has to be separated from the blood or tissue. The gold standard for drug identification is gas chromatography-mass spectrometry, an instrument that looks at drugs at the molecular level. Its even more advanced version is called liquid chromatography tandem mass spectrometry. You go through and run individual tests, running a specific test to get a level of a specific drug, said Dr. Daniel Spitz, chief medical examiner in Macomb and St. Clair Counties in Michigan. This process could take several days depending on the types of drugs found in the body. And drugs could be present in very minute levels, in measurements like parts per million or parts per billion. Rohde likens it to searching for five black marbles in a pile of 1 million white marbles. In the final step, the toxicologist reviews the evidence and determines whether drugs found in the body were enough to kill an individual. That report is submitted to the coroner or medical examiner, at least in the United States. Cases involving Michael Jackson, Heath Ledger and Anna Nicole Smith were complicated because they had several different drugs in their bodies some of the substances weren t in the regular menu in the toxicology lab, Rohde said.


Anytime you have a notorious person die of suspect means and they have past history of drug abuse, the toxicology report is very important, he said. You don t want to rush it. In a high-profile case like Winehouse s, it is most likely that the lab will run several tests to confirm its findings. Follow According to on WebMD, there are a few potential causes. The most important thing to remember is that there are likely thousands, if not more, of known chemicals and related metabolites that can be present in an individual and responsible in some part for their death. It simply is not possible to screen for all possible chemicals at once because both the cost and time scale needed is prohibitive. In addition, it is not likely that a single lab could test for all of these chemicals because doing such would require an enormous facility with a large number of different machines and specialized technicians. Thus it s easier for there to be numerous specialized labs that may be required for testing. The first test tends to be used to detect very general classes of chemicals that may be present. An immunoassay is commonly used to determine which antibodies are present in the sample to see if amphetamines, barbiturates, opiates, etc are present. Wherever a positive match comes up, an array of more specific tests are run to identify what the precise compound is and what the dose may have been.


The latter tests are commonly sent our to specialized labs, which adds on time for shipping. These specialized labs may make use of fairly quick tests or they may be required to perform tests that are multi-step and require days for some steps to complete, such as with gas chromatography. Samples from a deceased individual may be fluids (blood, urine, etc) or tissues (kidney, liver, etc) so the first availability of the sample will not usually be until after the coroner has done his/her work. It is also necessary to receive information from a field investigation to provide leads about which tests should be performed, usually based on the presence of narcotics or prescriptions on the individual, in their property, or in their name. Lastly, all of this needs to be done with a large paper trail. In addition to their being industry standards, the paper trail is immensely important in the legal world, such as in criminal persecution. Thus you could have situations where test results are duplicated to ensure that they are correct. From there, toxicologists need to consider the evidence and the possibility of synergistic effects to give their professional opinion about whether or not a person s death may have been caused by the chemicals they have found in their analysis.

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