Sports Toxicology

Obtaining samples from athletes shares many similarities with forensic sampling. The samples must be collected under tightly controlled conditions in which there is no question from whom or where the sample came. The samples must be kept safe and covered by a chain-of-custody document indicating who had control of the samples from collection through analysis and disposal. How these requirements are met is governed by the sports authority that oversees that particular sport and athlete.

The National Collegiate Athletic Association, for example, stipulates how urine is to be collected for analysis for what it classifies as banned

Lab technician Li Zhang performs a density test from urine samples at the Australian Sports Drug Testing Laboratory in Sydney, September 1, 2000. Starting the following day, the Australian Sports Drug Agency was contracted by the International Olympic Committee to conduct at least 400 pre-Olympic Games tests. (AP Photo/Rick Rycroft)

Lab technician Li Zhang performs a density test from urine samples at the Australian Sports Drug Testing Laboratory in Sydney, September 1, 2000. Starting the following day, the Australian Sports Drug Agency was contracted by the International Olympic Committee to conduct at least 400 pre-Olympic Games tests. (AP Photo/Rick Rycroft)

used for samples. Within minutes of death insects arrive on the body, which becomes the basis of a small ecosystem. The first insects to arrive are flies, followed by successive waves of other insects that feed on the body and/or on other insects already there. The insects that feed on the body consume the cocaine that the person had taken as well. In some cases it is possible to analyze the insects and discover cocaine or cocaine metabolites within their bodies. The same is true of many drugs and poisons; their presence in insects can indicate that the deceased person had taken them just prior to death.

The third general area of toxicology that has forensic aspects is the type used in workplace drug testing. People who work in law enforcement, many government agencies, and many private companies are substances. Interestingly, not all of the banned substances are illegal drugs. They are prohibited, however, because an athlete taking them may have an unfair advantage over other athletes who do not take them. The procedure for collection starts when the athlete arrives at a collection station, where he or she selects a beaker to use. Until the athlete delivers 85 ml of urine (while being watched by a crew chief), he or she stays in the collection station. If the athlete is unable to deliver enough urine in one event, he or she can drink approved beverages from sealed containers kept at the collection station for such situations.

The urine must have a pH between 4.5 and 7.5 and a specific gravity of above 1.005 (any lower suggests the possibility of dilution). Once the urine meets these specifications, it is divided into two containers, approximately 60 ml in "A" and the rest in "B." Both the crew chief and athlete witness all these steps, including the creation of the chain-of-custody forms. The samples are then delivered to the laboratory for testing. The results are used to insure that the athlete is not using banned substances.

74 drugs, poisons, and chemistry

POSTMORTEM SAMPLES USED iN TOXiCOLOGY

Specimen

Amount

always collected

blood (heart)

25 ml

(drawn peripherally)

10 ml

always collected

urine

all

usually collected

vitreous humor (fluid behind the lens of the eye)

all

usually collected

gastric contents

all

usually collected

bile

all

usually collected

brain

100 g

usually collected

liver

100 g

usually collected

kidney

50 g

usually collected

hair

varies

collected in some cases

spleen

varies

collected in some cases

fatty tissue (adipose)

varies

collected in some cases

lung

varies

collected in some cases

muscle tissue

varies

(forensic entomology)

varies

collected in some cases

bone marrow

varies

collected in some cases

intestine

varies

required to undergo drug testing as a condition of their hiring or maintaining a job. The substance tested is urine, and the procedures for collection are strict and tightly controlled. This type of toxicology is performed in private toxicology laboratories, and the practice of workplace drug testing is becoming quite common both in government and private settings.

POISONS

Broadly speaking, there are three classes of poisons studied by forensic toxicologists. The first are those of plant origin, such as hemlock and strychnine. The second type is the heavy metals (and other elements), including arsenic, thallium, lead, mercury, beryllium, and cadmium. The third class contains gases, including carbon monoxide (CO) and hydrogen cyanide (HCN), which was once used in gas chamber executions. Powdered cyanide, most often in the form of sodium cyanide (NaCN) or potassium cyanide (KCN), is a lethal poison in its own right that falls outside these loose divisions.

KCN was used in the Tylenol tampering case in 1982 that occurred in Chicago. In that case powdered cyanide was added to several bottles of Tylenol, resulting in the death of seven people and the classification of product tampering as a federal offense. Forensic chemists working that

The Death of Socrates by Charles Alphonse Dufresnoy (1611-68). Created in 1650, the painting is in the Galleria Palatina of the Palazzo Pitti, Florence, Italy. (Alinari/Art Resource)

The structure of coniine, the toxin in hemlock

G Infobase Publishing

year were inundated with suspicious powders submitted by a nervous public and law-enforcement officials. A similar situation occurred in 2001 in the immediate aftermath of the anthrax mailings. In that incident a still unknown person or persons sent anthrax powder through the mail to several places along the East Coast of the United States. More than 20 people developed an infection, and five died.

Plant poisons generally belong to a chemical class called alkaloids, the same group that contains caffeine. According to an account written by the Greek philosopher Plato, Socrates was executed by being forced to drink an extract of a plant that is presumed to have been hemlock. The hemlock plant, Conium maculatum, was known to be poisonous, acting on the nervous system and causing paralysis. The toxic agent in hemlock is called coniine. Other plant poisons include atropine (extracted from the nightshade plant, Atropa belladonna) and many species of mushrooms. Since September 11, 2001, there has been increasing concern about a poison called ricin, which can be extracted from castor beans (Ricin communis). The toxin is a complex protein molecule that in small doses can stop critical cell functions and cause death. In late 2003 and 2004 the FBI reported that several offices in Washington, D.C., had received letters that contained a powdery material suspected to contain ricin. The poison is much more lethal when injected than inhaled or ingested.

Once forensic toxicology was an established science and laboratory methods became reliable, the use of metals as poisons dropped dramatically. Heavy-metal poisoning still occurs but mostly by accidental exposure from materials in the environment. Lead, once a common ingredient in paint, still poisons children who eat or otherwise ingest paint chips that contain it. Lead is also found as an environmental contaminant of soils and waters. As with many heavy metal poisons, its effects tend to be more severe in children than in adults. Mercury is another environmental poison, particularly when it is in the form of methyl mercury or dimethyl mercury (CH3-Hg-CH3).

Of the three major categories of poisons toxic gases are responsible for a large number of deaths each year. One culprit is CO, produced as a by-product of combustion. Anytime there is a fire or open flame, significant amounts of CO can be produced. Cars are based on internal combustion, so car exhaust contains CO. As a result vehicle exhaust is sufficiently poisonous to kill and is not an uncommon method of committing suicide. Accidental CO poisoning occurs when heaters that use flames malfunction or are brought into a home. Barbeque grills and propane stoves can produce significant amounts of CO, and every year several deaths result from faulty heaters during the winter months, when homes are typically sealed up tight.

Another combustion product, HCN, is a very toxic substance that can also be formed when synthetic materials such as plastics or fabrics burn. Normally a person who does not smoke will have a trace level of cyanide in his or her blood. Smokers have about twice that level, or around 0.04 |g/ml. Amounts that exceed about 2.5 |g/ml can be quickly fatal. Another way HCN is produced is when an acid is added to a powdered form of cyanide, which is how HCN was generated in gas chamber executions.

Measurement of CO and cyanide levels in blood is especially useful when a person is found dead after a fire. The immediate forensic question is "Did this person die as a result of the fire or was he or she dead before?" If the person was breathing during the fire, there will be elevated levels of both compounds in the person's blood. If the person was not breathing when the fire was burning, the levels should be near normal. The longer the victim was breathing during the fire, the higher the levels. This testing is important because in murder cases it is not unusual for the killer(s) to attempt to destroy evidence by setting a fire. In these cases the findings of the forensic toxicologist are critical.

Given the progress in forensic chemistry and forensic toxicology, intentional poisoning as a means to commit murder is rare. This does not mean that there is no poisoning, just that the use of poison as a murder weapon has greatly decreased as the skill and expertise of forensic chemists and forensic toxicologists have increased. Nor does this mean the end of poisoning, just that most poisonings now are accidental or the result of environmental exposure. In 2005 more than 2 million cases of poisoning were reported to the American Association of Poison Control

Centers. Of these more than 1,200 cases resulted in death. Of the total number of reported incidents nearly 84 percent were accidental or unintentional poisonings. Sadly, a large number of poisonings are also self-inflicted as a means of committing suicide, with just over 8 percent of the reported poisonings attributed to suicides or suicide attempts. Malicious poisonings accounted for less than 1 percent of the total reported poisonings, a low number that has much to do with progress in forensic chemistry and the skill of forensic toxicologists.

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