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Up Coming Webinar: Forensic Science: What Writers Need To Know


FORENSICS FOR DUMMIES Info

One week left to sign up for “Forensic Science: What Writers Need To Know”
Join me Tuesday, February 25, 2020, 4 pm Pacific for this SISTERS IN CRIME WEBINAR

Topics to be covered include:

What is evidence and how is it used?
The ME’s 3 Questions: What is the Time, Cause, and Manner of Death?
Forensic Toxicology: The How, Where, and How Much
What’s new with DNA?

And more.

Bring your questions and join us.

Info/Registration: https://www.sistersincrime.org/events/EventDetails.aspx?id=1322890

 

HOWDUNNIT:FORENSICS Info

 

 
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Posted by on February 17, 2020 in Writing

 

Criminal Mischief: Episode #33: Toxicology Part 2

LISTEN: https://soundcloud.com/authorsontheair/episode-33-toxicology-part-2

PAST SHOWS: http://www.dplylemd.com/criminal-mischief.html

SHOW NOTES:

From HOWDUNNIT: FORENSICS

TOXICOLOGICAL TESTING PROCEDURES 

The biggest problem facing the toxicologist is that there are literally thousands of drugs and chemicals that are harmful, addictive, or lethal if ingested, injected, or inhaled. Some even absorb directly through the skin. Toxicological testing is time-consuming and expensive, and few, if any, labs can afford to perform such testing on every case. For this reason, the testing must be as focused as possible. 

An understanding of the circumstances surrounding the death is important since clues at the scene often point toward a particular drug. For example, a young girl found on her bed at home with an empty pill bottle at her side would lead to one avenue of testing while a long-term addict found in an alley with fresh needle marks would follow another path. The more clues as to the likely toxin that the circumstances of the death can supply, the narrower the field of possibilities the toxicologist must consider. 

THE TWO-TIERED SYSTEM 

When testing for drugs or poisons, the toxicologist typically follows a two-tiered approach. Initial tests, called presumptive tests, are for screening purposes and are typically easier and cheaper to perform. When negative, they indicate that the drug or class of drugs in question is not present and further testing is unnecessary. When positive, they indicate that a particular substance possibly is present. By using these screening tests the number of possibilities can be greatly reduced and the toxicologist can move on to the second phase, which utilizes more focused confirmatory testing. These tests are more expensive and time-consuming but are designed to establish the identity of the exact drug present. This two-tiered approach saves considerable time and money. 

This same approach is used whether the toxicologist is asked to analyze blood, urine, and other materials obtained from a person (living or deceased) or to test a batch of seized material believed to be illicit drugs. 

Let’s say a corpse is found in an alleyway known for methamphetamine sales and use. If blood samples obtained at autopsy show a positive presumptive test for amphetamines, further confirmatory testing to identify the exact amphetamine present is indicated. If the test is negative, no further testing for amphetamines is done and the toxicologist will search for other classes of drugs. 

To be doubly certain, the toxicologist prefers to find the drug or poison in at least two separate locations. Finding the toxin in the blood and the liver tissue is more reassuring than finding it in either one alone. 

Or let’s say that the toxicologist is asked to test a seized substance and doing so shows a positive presumptive test for cocaine. Further confirmatory testing would then be indicated. If the screening test is negative, the substance may be analyzed for other drugs, but cocaine has been ruled out. 

In most labs, testing for controlled and illegal drugs consumes 75 percent of the lab’s time and resources. The areas most often tested in this type of examination are blood and urine. After one of the presumptive tests shows that a particular drug or class of drugs is likely present, confirmatory testing with the combination of gas chromatography and mass spectrometry (GC-MS) or infrared spectroscopy are used to accurately identify which substance is present. See the appendix for details on these procedures. 

Presumptive Tests 

Presumptive testing comes in many varieties. Common toxicological screening tests are color tests, immunoassays, thin layer chromatography, and ultraviolet spectroscopy. 

Color Tests 

Tests in which a reagent (any active chemical solution) is added to blood, urine, or tissue extractions, and if the particular chemical tested for is present, a color change reaction will occur. The color change results from a chemical reaction between the drug and the reagent, which produces a new compound that imparts a specific color to the mixture. These tests are cheap, easy, and quick, and can determine if a specific chemical or class of chemicals are present in the material tested. If it does not indicate that the toxin is present, further testing is not necessary.

There are a wide variety of color tests that reveal the presence of many types of drugs. Some of the most common are: 

TRINDER’S TEST: This reagent, containing ferric nitrate and mercuric chloride, turns violet in the presence of salicylates (aspirin and similar compounds). 

MARQUIS TEST: This reagent contains formaldehyde and sulfuric acid and turns purple in the presence of morphine, heroin, and most opiates, and brownish orange if mixed with amphetamines or methamphetamines. 

VAN URK TEST: This is a test for LSD and other hallucinogenic drugs. The reagent is a mixture of dimethylaminobenzaldehyde, hydrochloric acid (HCl), and ethanol. It turns purple to indicate a positive reaction. 

DILLIE-KOPPANYI TEST: In this test, the sample is treated with cobalt acetate in methanol and then with isopropylamine in methanol. It turns violet-blue if barbiturates are present. 

DUQUENOIS-LEVINE TEST: This three-step test determines if marijuana or other cannabinoids are present. The sample is treated with a mixture of vanillin and acetaldehyde in ethanol, then with HCl, and finally with chloroform. A deep purple color is a positive result. 

SCOTT TEST: This is also a three-step test that uses a mixture of cobalt thiocyanate and glycerine, followed by HCl, and then chloroform. Cocaine turns blue after the thiocyanate is added, changes to pink with the HCl, and then blue once again when chloroform is added. 

Other Screening Tests 

IMMUNOASSAY: Immunoassays, which measure the concentration of a drug in a liquid (see the appendix), are easy, very sensitive, and useful for rapidly screening urine samples for certain drugs. However, the manufactured antibodies can also react with compounds that are very similar to the sought-after drug, a lack of specificity that makes this a presumptive test rather than a confirmatory one. 

THIN LAYER CHROMATOGRAPHY (TLC): TLC (see the appendix) not only tentatively identifies many chemicals, but is also useful for separating the components of a sample. Once TLC has tentatively identified a substance, its identity is confirmed with mass spectrometry. 

GAS CHROMATOGRAPHY (GC): As with TLC, GC’s (see the appendix) primary use is in making a presumptive identification and separating various compounds from one another. A positive result is confirmed by using mass spectrometry. 

ULTRAVIOLET (UV) SPECTROSCOPY: This test takes advantage of the fact that different chemicals absorb UV light in varying amounts (see the appendix). Since it can’t identify the exact compound, it is only useful for screening

. 

A Typical Screening Protocol 

Each lab has its own protocol for drug screening. What tests are used and in what order they are performed depends on the available staff and equipment, budgetary restrictions, and the bias of the toxicologist in charge. But most labs have certain standard screens they employ when first confronted with an unknown sample. These basic screens might include:

ALCOHOL SCREEN: GC is used to isolate and identify the various alcohols and related compounds such as acetone. 

ACID SCREEN: Immunoassay of urine samples is used to detect acidic compounds such as barbiturates and aspirin. 

ALKALI SCREEN: GC screens for substances that dissolve in alkaline solutions. These substances include many tranquilizers, synthetic narcotics, and antidepressants. 

NARCOTIC SCREEN: Urine immunoassay reveals opiates, cocaine, and methadone. 

By using these general screening procedures, the toxicologist can quickly exclude many commonly encountered drugs and narrow his area of search for those that are present. Based on these results, further screening and confirmatory tests are used to ultimately identify any unknown substance. 

Confirmatory Tests 

A good confirmatory test must possess sensitivity and specificity in that it must recognize the chemical in question (sensitivity) and be able to identify it to the exclusion of all others (specificity). This means that once a chemical has undergone a screening test and a presumptive identity has been established, a confirmatory test will accurately determine the true identity of the unknown substance. 

The most important confirmatory test used by the toxicologist is mass spectrometry (MS) (see the appendix). In MS, the sample is bombarded with electrons, which fragment the chemical into ionic fractions. This fragmentation pattern is called a mass spectrum. It is different for each element and compound. This means that it gives a chemical fingerprint of the chemical being tested and can identify virtually any compound. When the mass spectrum of an unknown substance is compared to known reference standards, the identity of the unknown sample comes to light. The National Institute of Standards and Technology (NIST) maintains a database of the mass spectra of known chemicals. 

In the forensic toxicology laboratory, MS is usually employed in combination with gas chromatography (GC). This combination is called gas chromatography/mass spectrometry (GC/MS). In GC/MS, gas chromatography is used to separate the test sample into components and MS is employed to identify each component. The GC/MS is as close to being foolproof as any technique available. 

Though used less often than MS, infrared spectroscopy (IR) can also determine the chemical fingerprint of the tested substance (see the appendix). Instead of electrons, the substance is exposed to infrared light. When any light strikes an object or substance, it is transmitted (passed through), absorbed, or reflected. When exposed to infrared light, each compound transmits and absorbs the light in its own unique pattern. These unique patterns determine which compounds are present, and thus identify the chemical substance tested. This test is also used in conjunction with GC. This combination is termed GC/IR. 

INTERPRETING THE RESULTS

After testing has revealed the presence and concentration of a chemical substance, the hard part begins. The toxicologist must now assess what the results mean. He evaluates each of the drugs present with an eye toward the route the drug was administered and whether the concentrations played a role in the subject’s behavior or death.

Route of Entry 

The route of entry of the toxin is very important since it might provide a clue as to whether the victim self-administered the drug or someone else administered the drug. For example, if a drug was injected and the victim possessed no means to do so or if the injection site was in an area that made self-administration unlikely, homicide might be a stronger consideration. 

Another important fact is that the concentration of the toxin is usually greatest at the administration site. Ingested toxins are more likely to be found in the stomach, intestines, or liver, while inhaled gases will be concentrated in the lungs. If injected, the drug can often be isolated from the tissues around the injection site. Drugs taken intravenously bypass the stomach and liver, directly enter the bloodstream, and are quickly distributed throughout the body. In this circumstance, the toxicologist may find high concentrations of the drug in the blood and in multiple tissues of the body, but little or none in the stomach and liver as would be seen with ingestion. This will help him determine the route of intake. 

Drug Blood Level 

Earlier we discussed the concept of bioavailability and how the level of a drug in the blood closely correlates with the drug’s actions and toxicity. This means that finding a large amount of a toxin in the victim’s stomach does not necessarily mean that the drug was the cause of death. The important fact is that drugs in the stomach will not kill. They must first be absorbed into the blood and distributed to the body. 

For example, if the toxicologist found a large amount of a tranquilizers in a victim’s stomach, particularly if most of the pills were intact and had not been digested, and also found a low blood concentration of the drug, he would likely conclude that the pills were taken shortly before death and played little or no role in the victim’s demise. 

There are exceptions. In cases of caustic acid and alkali (lye or caustic soda) ingestion, the blood levels are not important since these chemicals cause direct contact damage and do not need to be absorbed into the body to do harm (discussed later in this chapter). 

Still, in most situations, blood levels are important because they correlate more strongly with the effects of the chemical in question. When the toxicologist determines a blood level of a certain chemical, he might assign it to one of four broad categories: 

NORMAL: This would be the level expected in the general population under normal circumstances. An example would be low levels of cyanide. Even though this is a deadly poison, it is found in the environment, and therefore most people have low normal levels of cyanide in their blood. Smokers have even higher levels, but this would still be considered normal. 

THERAPEUTIC: This is the level that your doctor strives for. If he gives you an antibiotic or a medication for high blood pressure, he wants to accomplish a blood level of the drug that will bring about a therapeutic effect. Patients with certain cardiac problems may be placed on digitalis. The doctor will periodically draw a blood test to check the therapeutic level of the drug. The reason he does this is that too little will offer less benefit to the patient and too much can cause severe problems since digitalis is potentially a deadly poison. 

TOXIC: A toxic level is one that may cause harm or death. When a prescribed drug passes the therapeutic level and reaches the toxic level it has moved from being a medication to being a poison. Using the example of digitalis, a toxic level might lead to nausea, vomiting, and a yellowish tinge to the person’s vision. Or it may cause a deadly change in the rhythm of the heart. These would be toxic effects. 

LETHAL: This is the level at which the drug in question would consistently cause death. In toxicology we use the term LD50 to measure a chemical’s lethal potential. The LD50 of a drug is the blood concentration at which 50 percent of people would die. 

From this, you might assume that the toxicologist simply has to determine the blood level of any toxin and then he can determine if the level was toxic or lethal. Though that may seem logical, it is far from the truth. 

Each person reacts to chemicals and toxins differently. Much of this variance can be related to age, sex, body size and weight, genetics, and nutritional and health status. An individual who is young, robust, and healthy should tolerate more of a given drug than would someone who was old, thin, and sickly. And in general, that is true. As mentioned earlier, a person’s habits also affect how he will react. The toxicologist must consider these facts when assessing whether a given level of a drug is toxic or lethal, or whether it contributed to the subject’s behavior or death. 

Acute vs. Chronic Poisoning 

At times the toxicologist is asked to determine whether a poisoning is acute or chronic. A good example is arsenic, which can kill if given in a single large dose or if given in repeated smaller doses over weeks or months. In either case, the blood level could be high. But the determination of whether the poisoning was acute or chronic may be extremely important. If acute, the suspect list may belong. If chronic, the suspect list would include only those who had long-term contact with the victim, such as a family member, a caretaker, or a family cook. 

So, how does the toxicologist make this determination? 

In acute arsenic poisoning, the ME would expect to find high levels of arsenic in the stomach and the blood, as well as evidence of corrosion and bleeding in the stomach and intestines, as these are commonly seen in acute arsenic ingestion. If he found little or no arsenic in the stomach and no evidence of acute injury in the gastrointestinal (GI) tract, but high arsenic levels in the blood and tissues, he might suspect that the poisoning was chronic in nature. Here, an analysis of the victim’s hair can be invaluable. 

Hair analysis for arsenic (and several other toxins) can reveal exposure to arsenic and also give a timeline of the exposure. The reason this is possible is that arsenic is deposited in the cells of the hair follicles in proportion to the blood level of the arsenic at the time the cell was produced. 

In hair growth, the cells of the hair’s follicle undergo change, lose their nuclei, and are incorporated into the growing hair shaft. New follicular cells are produced to replace them and this cycle continues throughout life. Follicular cells produced while the blood levels of arsenic are high contain the poison, and as they are incorporated into the hair shaft the arsenic is, too. On the other hand, any follicular cells that appeared while the arsenic levels were low contain little or no arsenic. 

In general, hair grows about a half-inch per month. This means that the toxicologist can cut the hair into short segments, measure the arsenic level in each, and reveal a timeline for arsenic exposure in the victim. 

Let’s suppose that a wife, who prepares all the family meals, slowly poisoned her husband with arsenic. She began by adding small amounts of the poison to his food in February and continued until his death in July. In May he was hospitalized with gastrointestinal complaints such as nausea, vomiting, and weight loss (all symptoms of arsenic poisoning). No diagnosis was made, but since he was doing better after ten days in the hospital, he was sent home. Such a circumstance is not unusual since these types of gastrointestinal symptoms are common and arsenic poisoning is rare. Physicians rarely think of it and test for it. After returning home, the unfortunate husband once again fell ill and finally died. 

As part of the autopsy procedure, the toxicologist might test the victim’s hair for toxins, and if he did, he would find the arsenic. He could then section and test the hair to determine the arsenic level essentially month by month. If the victim’s hair was three inches long, the half-inch closest to the scalp would represent July, the next half inch June, the next May, and so on until the last half inch would reflect his exposure to arsenic in February, the month his poisoning began. Arsenic levels are ex-
pressed in parts per million (ppm).

The toxicologist would look at this timeline of exposure and likely determine that the exposure occurred in the victim’s home. The police would then have a few questions for the wife and would likely obtain a search warrant to look for arsenic within the home. 

To dig deeper into this subject grab a copy of either 

FORENSICS FOR DUMMIES: http://www.dplylemd.com/book-details/forensics-for-dummies.html

or 

HOWDUNNIT: FORENSICS: http://www.dplylemd.com/book-details/howdunnit-forensics.html

 
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Posted by on February 11, 2020 in Uncategorized

 

STRESS FRACTURE To Be Re-released

 

STRESS FRACTURE, Dub Walker #1, will soon be re-released with a new cover. Medallion went belly up but Suspense Publishing stepped in to revive this the first Dub Walker thriller.

Details will be coming soon. http://www.dplylemd.com/book-details/stress-fracture.html

 

 
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Posted by on January 25, 2020 in Writing

 

The Date Rape Drugs Are Still Alive

The Date Rape Drugs Are Still Alive

Though you might not have heard much about them lately, the so-called Date Rape Drugs are still around. Make no mistake about that. Many years ago they were in the news all the time. A woman sitting in a bar or a kid at a rave would have something added to their drink and hours later they would wake up in a strange place with a strange person. That’s the danger of these types of drugs. They make the victim very compliant, highly suggestible, and erase any memory for the events that occurred while under the influence of the drug.

Robert Koester

A recent case involving Robert Koester underlines the fact that these drugs are still a problem. I don’t believe it’s been determined what drug he used but allegedly over the past 25 years he has drugged and assaulted many young models. Apparently, he’s a photographer of sorts. I suspect that his most recent victims will have been given GHB because it’s commonly available. Rohypnol, another possibility, is harder to come by these days but is still out there.

http://www.newser.com/story/270990/photographer-accused-of-drugging-molesting-underage-models.html

https://www.nbcsandiego.com/news/local/robert-koester-model-photographer-accused-assault-abuse-misconduct-sexual-minor-plea-guilty-561451771.html

 

 

Andrew Luster

This case echoes the famous Andrew Luster case. You might remember he was the heir to the Max Factor fortune and was accused of drugging and assaulting many young women. He ultimately was sentenced to 124 years in jail but failed to show up for his sentencing hearing—Gee, I wonder why?—and fled to Mexico. Dog the Bounty Hunter tracked him down and returned him to the US for incarceration.

https://en.wikipedia.org/wiki/Andrew_Luster

 

 

 

There have been numerous similar cases in the past. People like Joseph Rivera, the team of Michael Hagemann and Danny Bohannon, and many others.

http://articles.latimes.com/1997/jul/04/local/me-9736

Here is an article I wrote on these drugs:

http://www.dplylemd.com/articles/date-rape-drugs.html

I have blogged about this issue and some of these cases on previous occasions:

https://writersforensicsblog.wordpress.com/2013/08/13/joseph-rivera-the-new-andrew-luster/

https://writersforensicsblog.wordpress.com/2010/10/12/date-rape-drugs-stealthy-and-dangerous/

In a recent podcast on Criminal Mischief: The Art and Science of Crime Fiction, I discussed how one fictional character can subdue and control another character by employing various means, including these types of drugs:

https://writersforensicsblog.wordpress.com/2018/10/02/criminal-mischief-episode-05-making-characters-compliant/

 
 

Criminal Mischief: Episode #32: Toxicology Part 1

Criminal Mischief: Episode #32: Toxicology Part 1

 

LISTEN: https://soundcloud.com/authorsontheair/episode-32-toxicology-part-1

PAST SHOWS: http://www.dplylemd.com/criminal-mischief.html

SHOW NOTES:

From HOWDUNNIT: FORENSICS

WHAT IS A POISON? 

The terms poison, toxin, and drug are simply different ways of saying the same thing. Though you might think that a poison kills, a toxin harms, and a drug cures, these terms can be used almost interchangeably. The reason is that what can cure can also harm, and what can harm can kill. 

Anything and everything can be a poison. The basic definition of a poison is any substance that, if taken in sufficient quantities, causes a harmful or deadly reaction. The key here is the phrase “sufficient quantities.” 

The toxicity of any substance depends on how much enters the body and over what time period it does so. For example, you probably know that arsenic is a poison, but did you know that you likely have arsenic in your body right now? If you’re a smoker, you have more than a little bit. Same with mercury and cyanide. These substances are in the environment—you can’t avoid them. But they are in such small quantities that they cause no real harm. However, take enough of any of them and they become deadly.

The same can be said for the medications your doctor gives you to treat medical problems. Consider the heart drug digitalis, which comes from the foxglove plant and has been used for over a hundred years to treat heart failure and many types of abnormal heart rhythms. It is also a deadly poison. Too much can lead to nausea, vomiting, and death from dangerous changes in the rhythm of the heart. It’s ironic that it can treat some abnormal heart rhythms while at the same time can cause other more deadly rhythms. It’s all in the dosage. The right dose is medication; the wrong dose is poison. 

TOXICOLOGICAL TESTING

Toxicology is a marriage of chemistry and physiology, since it deals with chemical substances (chemistry) and how these substances alter or harm living organisms (physiology), particularly humans. 

A forensic toxicologist deals with the legal aspects of toxicology. His job is to find and analyze toxic substances in biological materials taken from both the living and the dead, and to determine the physiological, psychological, and behavioral effects on the individual in question. For example, he might be asked to assess the state of inebriation of an automobile accident victim or to determine if someone died from a poison or if the presence of a drug contributed to the victim’s death. This is often more difficult than it sounds. 

When the toxicologist investigates a possible poisoning death, he must answer three basic questions: 

Was the death due to a poison?

What was the poison used?

Was the intake of the poison accidental, suicidal, or homicidal? 

During his analysis, the modern forensic toxicologist sometimes searches for the poison itself, while other times he searches for the poison’s breakdown products. This brings up the concept of biotransformation, which is the conversion or transformation of a chemical into another chemical by the body. We also call this metabolism and the new product produced a metabolite. This process is simply the body destroying or breaking down chemicals and excreting them from the body. This is why you must take most medications each day. The medication is designed to treat some medical problem, and indeed it may do that. But, to the body, the drug is also a foreign toxin and as such must be metabolized and excreted. So, you have to take another dose day after day to keep the blood level of the medication in the therapeutic level. 

The metabolism of a drug or toxin typically deactivates the chemical and prepares it for elimination from the body, usually by way of the kidneys. For example, many chemicals are not soluble in water, which means they aren’t soluble in urine, either. The body gets around this by metabolizing (biotransforming) the chemical in such a way that it becomes a new chemical (metabolite) that is water soluble. The metabolite can then be filtered through the kidney, into the urine, and out of the body.

Most metabolites are inactive in that they possess no biological activity and are inert as far as the body is concerned. Other metabolites are active and may have biological properties that are weaker or stronger than the original compound. They may even behave quite differently from the parent compound. For example, cocaine is metabolized into three metabolites: nor-cocaine, which possesses active properties, and benzoylecgonine and methylecgonine, which are inert. 

Another example is heroin, which is made from morphine. When heroin is injected into the bloodstream it is immediately converted back into morphine— the chemical that gives the user the “high.” 

Since both cocaine and heroin are metabolized to new compounds very quickly, testing for either would be useless. Instead, the toxicologist tests for the presence of cocaine or heroin by searching for their metabolites. Finding them proves that the parent drug was present. 

One of the reasons poisoning has been such a popular means for homicide for so many years is that most poisons cause no visible changes in the body, either in the living person or at autopsy. In the days before toxicology labs existed, the poisoner “got away with it” more often than not. After all, if there were no obvious reason for the death, it must have been natural. Since the true cause of death could not be determined, no one could be held responsible. 

Of course, some toxins do leave behind visible signs, many of which have been known for years. Corrosive poisons such as acids and lye cause severe damage to the mouth, esophagus, and stomach if they are ingested. Poisonous mushrooms and chlorinated hydrocarbons such a carbon tetrachloride, which for years was used in many carpet cleaners, may cause fatty degeneration of the liver. Cyanide and carbon monoxide cause a cherry-red appearance to the blood and tissues and lead to pinkish lividity. Metallic poisons such as arsenic, mercury, and lead cause characteristic changes in the gastrointestinal tract and the liver. 

But this isn’t the norm. Most poisons work their mischief within the cells of the body and leave behind no visible footprints. This means the ME does not often see visible evidence of toxins at autopsy or on the microscopic slides he prepares from the body’s tissues. Instead he collects fluids and tissues from the body and these are analyzed for the presence or absence of toxins by the toxicologist. 

SAMPLE COLLECTION 

Since toxins rarely leave behind visible clues, the ME and the toxicologist must perform specialized tests to reveal their presence. These examinations require various body fluids and tissues, and which ones are used depends on the particular drug in question and the situation under which it is tested. The goal of testing is to establish whether a particular drug is the cause of death, or a contributing factor in the death, or that it played no role at all.

The best places to obtain samples for testing are the locations where the chemicals entered the body, where they concentrate within the body, and along the routes of elimination. This means that blood, stomach contents, and the tissues around injection sites may possess high concentrations of the drug. Analysis of liver, brain, and other tissues may reveal where the drug or its metabolites have accumulated. Finally, urine testing may indicate where the drug and its metabolites are concentrated for final elimination. 

During an autopsy, blood, urine, stomach contents, bile, vitreous eye fluid, and tissue samples from the liver, kidneys, muscles, and brain are obtained. If an inhaled toxin is suspected, lung tissue is also taken, and if a chronic heavy metal (arsenic, lead, etc.) poisoning is a consideration, hair samples are taken (the reason is discussed later in this chapter). 

It is important that the samples be collected before embalming, since this procedure can interfere with subsequent testing or, as in the case of cyanide, completely destroy the toxin. Also, since embalming fluids may contain methanol and other alcohols, accurate alcohol testing is difficult if not impossible after this procedure.

Let’s look at the most common fluids and tissues obtained by the ME or toxicologist.

BLOOD: Blood is by far the toxicologist’s most useful substance since, with modern toxicological techniques, most drugs and their major metabolites can be found in the blood. 

Blood is easily sampled from the living with a simple venipuncture (using a needle to draw blood from a vein, usually in the arm). During an autopsy, blood is typically obtained from several areas. The aorta (the main artery that carries blood out of the heart and to the body), both sides of the heart, and the femoral artery (in the groin area) are common locations. The samples are then placed into glass tubes and sent to the laboratory for testing. If the blood is to be analyzed for volatile chemicals, a sample is placed in a Teflon-lined screw-cap tube. Rubber stoppers should be avoided since they can react with the gases or may also allow them to escape. 

The toxicologist not only determines if the toxin is present, but also attempts to assess its level in the body. This is important since low levels may be of no consequence, higher doses may have toxic effects and may have contributed to the person’s actions or played a role in his death, and even higher levels may have been the actual cause of death. Blood is most often the best substance for this assessment. 

Concentrations of medicines and drugs within the blood correlate well with levels of intoxication as well as with levels that are potentially lethal. Bioavailability is the amount of the drug that is available for biological activity. Since drugs work on the cellular level, bioavailability means the concentration of the drug that reaches the cells of the body. For most chemicals, the blood level correlates with the cellular level. 

For example, the level of alcohol in the blood correlates extremely well with a person’s degree of intoxication, and the lethal level of alcohol in the blood is well known. This knowledge means that the ME can use a blood alcohol level to accurately estimate a person’s degree of intoxication in an automobile accident or whether the fraternity boy died from his binge drinking or from some other cause. 

Or let’s say that an individual takes a handful of sedative (sleeping) pills in a suicide attempt. In order for the pills to “work” they must be digested, absorbed into the bloodstream, and carried to the cells of the brain, where the concentration of the drug in the brain cells determines the degree of “poison- ing.” And since the amount of the drug in the blood is an accurate reflection of the amount within the brain cells, testing the blood is like testing the cells. 

But, if absorption of the pills from the stomach doesn’t occur, the person will have no effect from the drug. The amount of the drug present in the stomach is irrelevant since it is not available to the brain cells. So, a victim found with undigested pills in his stomach and a very low blood level of the drug did not die from a drug overdose and must have died from something else. 

URINE: Easily sampled with a cup and a trip to the restroom, urine testing is a staple of workplace drug testing. It is also useful at autopsy, where it is re- moved by way of a needle inserted into the bladder. Because the kidneys are one of the body’s major drug and toxin elimination routes, toxins are often found in greater concentrations in the urine than in the blood. However, one problem is that the correlation between urine concentration and drug effects in the body is often poor at best. All the urine level can tell the ME is that the drug had been in the blood at some earlier time. It can’t tell him if the drug was exerting any effect on the individual at the time of its collection, or in the case of a corpse, the time of death. 

Also, estimating blood concentrations from urine concentrations is impossible. The concentration of any drug in the urine depends on how much urine is produced. If the person has ingested a great deal of water, the urine and any chemicals it contains will be more diluted (watered down) than if the person is “dry.” In addition, alcohol and drugs known as diuretics increase urine volume and decrease the urine concentration of any drugs or metabolites present. Many athletes use diuretics in an attempt to mask or dilute performance-enhancing drugs. 

STOMACH CONTENTS: The stomach contents are removed from survivors of drug ingestions by way of a gastric tube, which is typically passed through the nose and into the stomach. The contents are then lavaged (washed) from the stomach and tested for the presence of drugs or poisons. 

At autopsy, the stomach contents are similarly tested. Obtaining the stomach contents in any case where poison or drug ingestion is suspected is critical. However, as mentioned earlier, the concentration of any drug in the stomach does not correlate with its blood level and thus its effects on the person. It does, however, show that the drug was ingested and in what quantity. 

LIVER: The liver is the center of most drug and toxin metabolism. Testing the liver tissue and the bile it produces can often reveal the drug or its metabolites. Many drugs, particularly opiates, tend to concentrate in the liver and the bile, so they can often be found in these tissues when the blood shows no traces. Where the liver might reflect levels of a drug during the hours before death, the bile may indicate what drugs were in the system over the past three to four days. Neither is very accurate, however. 

VITREOUS HUMOR: The vitreous humor is the liquid within the eyeball. It is fairly resistance to putrefaction (decay) and in severely decomposed corpses it may be the only remaining fluid. Testing may uncover the presence of certain drugs. 

The vitreous humor is an aqueous (water-like) fluid, which means that chemicals that are water soluble will dissolve in it. It also maintains equilibrium with the blood, so that any water-soluble chemical in the blood will also be found in the vitreous. The important thing is that the level in the vitreous lags behind that of the blood by about one to two hours. This means that test- ing the vitreous will reflect the concentration of the toxin in the blood one to two hours earlier. 

HAIR: Hair absorbs certain heavy metal (arsenic, lead, and others) toxins and some other drugs. It has the unique ability to give an intoxication timeline for many of these substances. This will be discussed in greater detail later in this chapter. 

INSECTS: In cases where the body is severely decomposed and insects have been feeding on the corpse, the maggots can be tested for drugs. And since some insects tend to concentrate certain drugs in their tissues, they may supply information that the drug was at least present in the victim. 

TOXICOLOGY AND THE CAUSE AND MANNER OF DEATH 

In the remote past, it was very difficult to determine why someone died, and virtually impossible to ascertain whether a poison was involved. Though modern toxicological techniques have changed things greatly, determining that poisoning was the cause of death remains one of the most difficult tasks facing the forensic toxicologist. 

The ultimate responsibility for determining the cause and manner of death lies with the ME or the coroner. To do this he will rely on the circumstances of the death, the crime scene reconstruction, the autopsy findings, and the laboratory results, including the toxicology findings. 

In cases where a potentially deadly poison is involved, the toxicologist must uncover the toxin, determine its concentration within the victim, and then give his opinion as to whether this level of this drug was likely lethal. To accomplish this he must consider a number of factors.

The lethal level for many drugs is extremely variable from person to per- son. Age, sex, body size and weight, the presence of other drugs or medications, the state of overall health, and the presence of other diseases impact a given person’s tolerance to some drugs. 

For example, a frequent and heavy drinker can tolerate much higher blood alcohol levels than could someone who never drank. A heavy drinker might appear completely sober at a level that would render the normal person unconscious. 

Similarly, hardcore heroin addicts routinely inject doses of heroin and attain drug blood levels that would kill the average person in a matter of minutes. 

In addition, some drugs are more dangerous to individuals with certain medical problems. The use of amphetamines poses a much greater risk for someone with heart disease or high blood pressure than it would for someone in good health. In this circumstance, a blood level of amphetamines that would not harm the average person could prove lethal for a person with these diseases. 

So, it’s not straightforward. When the ME attempts to determine the cause of death in the presence of drugs or toxins, he must consider all these factors. In the absence of other possible causes of death, and with the presence of significant levels of a potentially harmful drug, he might conclude the drug was the proximate cause of death or at least a contributing factor. 

Remember that the manners of death are natural, accidental, suicidal, homicidal, and the extra classification of undetermined. Drugs and poisons can be the direct cause or at least a contributing factor in any of these. 

NATURAL: A person can die of natural causes even if drugs are involved in the mechanism of death. What if a man with significant coronary artery disease (CAD) took an amphetamine or snorted a few lines of cocaine? Coronary artery disease is a very common disease in which the coronary arteries that supply blood to the heart are plugged with cholesterol plaque. 

Amphetamines and cocaine are drugs that increase the heart rate and the blood pressure, both of which increase the need for blood supply to the harder working heart muscle. In addition, these drugs can cause the coronary arteries to spasm (squeeze shut), which greatly decreases the blood supply to the heart muscle. Basically, the supply of blood is reduced at a time when the need is increased, so that the person loses both sides of the supply and demand equation. The victim could suffer a heart attack (actual death of a portion of the heart muscle due to lack of adequate blood supply) or a cardiac arrhythmia (a dangerous change in heart rhythm). Either of these could kill the victim. The cause of death would be a heart attack or a cardiac arrhythmia, events that he would be prone to due to his CAD. But, the amphetamine or cocaine would be a contributory factor. This circumstance is common.

When the ME and the toxicologist confront this situation, they must assess the extent of the victim’s heart disease, the amount of the drug in the body, and whether a heart attack actually occurred. If the amount of drug is low and the victim had severely diseased coronary arteries, they might conclude that the death was natural and that the drug was only a minor contributing factor. On the other hand, if his CAD was mild and the level of drug in his body was high, they might favor an accidental drug death. 

But, what if the victim intentionally took a large amount of cocaine, or what if the amphetamines were given to him without his knowledge? The manner of death would then be a suicide or a homicide, respectively. The important point is that the autopsy and lab results would be the same in each circumstance. The ME would need to rely on witness statements and the results of the police investigation to sort this out. And even with this information, the picture might simply be too muddy for the ME to determine the manner of death, and it might be classified as undetermined. 

ACCIDENTAL: Most accidental poisonings occur at home and often involve children. Curious by nature, children will eat or drink almost anything: prescription drugs, pesticides, household cleaners, paint thinners, weed killers, snail bait, you name it. In adults, accidental poisoning most often occurs because some product is mislabeled, usually because it has been placed in a container other than its original one. This may be in the form of medications dumped into another bottle, some toxic liquid placed in an empty liquor bottle, or the white powders of cyanide or arsenic stored in a container where they could be confused with sugar or salt. 

In other situations, the death might be the result of a dosage miscalculation. Addicts often miscalculate the amount of heroin or amphetamine they are taking and die from this error. The fact that street drugs have poor quality control only adds to this problem. How much heroin is actually in the bag the addict just bought? It may be less or many times more than the bag he purchased yesterday. If the latter is the case and he injects the same dose as he did yesterday, he could easily die from an overdose. 

Similarly, some people believe that if one dose of a drug is good, then two must be better. This is a dangerous assumption. Digitalis is a common cardiac medication. Sometimes a patient will decide on his own to double his dose. All is well for a couple of weeks, but as the medicine accumulates within his body, he becomes ill and can die. 

Another factor in accidental drug deaths is the mixing of drugs. Alcohol taken with a sedative is notorious for causing death. Addicts often mix cocaine with amphetamines, or heroin with tranquilizers, or just about any combination imaginable, often with tragic results. 

SUICIDAL: Drugs are a commonly involved in suicides. Sedatives or sleeping 

pills, narcotics, alcohol, and carbon monoxide (see Chapter Eight: Asphyxia, “Toxic Gases”) are commonly used. Often the victim takes multiple drugs, basically whatever is in the medicine cabinet. This presents a difficult problem for the toxicologist. He must analyze the stomach contents, blood, urine, and tissues, and hopefully determine the level of each drug and assess the contribution of each to the victim’s death. He may find that one particularly toxic drug was present in large amounts and that it was the cause of death. Or he might find that a certain combination of drugs was the cause. 

The ME uses these findings in conjunction with information from the autopsy and from investigating officers to assess the manner of death. The find- ing of multiple drugs in the victim’s system doesn’t necessarily mean that he took them on purpose. It could have been an accidental overdose driven by the need for relief of physical or psychological pain, or someone else could have surreptitiously slipped the drugs into his food or drink, which would be a homicide.

HOMICIDAL: Though homicidal poisoning was common from antiquity to the twentieth century, it is uncommon today. 

As with accidental and suicidal poisonings, homicidal poisonings occur most often at home. This means that the killer must possess knowledge of the victim’s habits and have access to his food, drink, and medications. This knowledge is critical in the homicidal administration of a toxin. It is also important in solving the crime. When the toxicologist determines that the victim was poisoned, the police focus on anyone who had access to the victim. 

To dig deeper into this subject grab a copy of either:

 

FORENSICS FOR DUMMIES: http://www.dplylemd.com/book-details/forensics-for-dummies.html

HOWDUNNIT: FORENSICS: http://www.dplylemd.com/book-details/howdunnit-forensics.html

 

Why I Love PI Novels

The Winter 2019/20 issue of Mystery Readers Journal is called Private Eyes II and has some interesting articles inside.

Mine is titled: “Why I Love PI Novels.” Check it out—-and join Mystery Readers International and subscribe to the Mystery Readers Journal: https://mysteryreaders.org

 

Why I Love P.I. Novels by DP Lyle

I’m not a P.I., nor do I play one on TV, but I do love P.I. crime fiction. Cops can be cool, and memorable fictional characters, but P.I.s seem to come in more and quirkier flavors. Some are tough, ex-military types, others seemingly everyday people with a knack for sniffing out wrongdoing, and still others are little old ladies with cats. The latter tend to be the smartest and toughest. It’s this great variety of characters that make reading P.I. stories so much fun. They tend to be more eccentric and possess different skills—even if they aren’t initially aware of them—than do most cop characters. And they all seem to break the rules with impunity. How much fun is that?

The fictional P.I. world is populated with iconic names: Holmes, Spade, Marlowe, Milhone, Hammer, Archer, Spenser, Cole, Bosch, Robicheaux, Rawlins, Cross, Drew, Drummond, Poirot, and so many others. Meeting such folks is why reading P.I. novels is so rewarding. And so much fun to write.

Each of my four thriller series features a private investigator, of sorts. None are what you would call a normal, licensed P.I. but each serves that function one way or the other. And they are very different characters.

Samantha Cody is an example. In the series of three books that feature Sam (DEVIL’s PLAYGROUND, DOUBLE BLIND, ORIGINAL SIN), her profession changes. Early in the series, she’s a cop in a small town in the California desert but after she loses that job she becomes involved in investigations, not professionally, but rather mostly for friends. Sam is also a professional boxer. She’s not that big but she’s tough and hits hard. She ultimately gives up that dream still undefeated. Too much wear and tear on the body is her take. Many fictional private investigators began as cops, most notably Michael Connelly’s Harry Bosch and James Lee Burke’s Dave Robicheaux. So Sam followed a traditional path.

My next series features Dub Walker (STRESS FRACTURE, HOT LIGHTS COLD STEEL, RUN TO GROUND). Dub doesn’t come from law enforcement. At least not in the traditional sense. He was an MP during his military years and later worked at a forensic science lab. He possesses a deep understanding of forensic science, crime scenes, and criminal behavior. He’s published several books on these subjects and basically works as a hired investigator for difficult cases. Each of the three novels featuring Dub unfolds after he is brought in as a consultant on a perplexing case.

My two current series, the Jake Longly and the new Cain/Harper series, also feature private investigators. Again, of sorts. 

Jake Longly, the protagonist of my series of comedic thrillers (DEEP SIX, A-LIST, SUNSHINE STATE, and the upcoming RIGGED) is a reluctant P.I., being dragged into that world kicking and screaming. Jake is an ex-professional baseball player. Pitcher for the Texas Rangers with an overpowering fastball. Until a rotator cuff injury derailed his career. Then he purchased Captain Rocky’s, a bar/restaurant on the sand in Gulf Shores, Alabama.

His current life goals are running his bar and chasing bikinis. Worthy aspirations to Jake. His father Ray feels otherwise. Ray has some murky background in the US military world of black ops and now runs a P.I. firm in Gulf Shores. He can’t understand why Jake won’t work for him and is constantly attempting to drag Jake into his world. Jake’s refusal creates tension, to say the least.

Jake has a girlfriend. Nicole Jamison. Insanely beautiful, but no bubble-headed bleach blonde. Not even close. Smart, clever, tough, and she doesn’t suffer fools well. Like Jake. And she works for Ray, sort of. Jake has a best friend—-Tommy “Pancake” Jeffers. Big doesn’t cover it. His hair is red and his ability to take in massive amounts of food legendary. Most people think he got his nickname from his ability to demolish a stack of pancakes, which of course he can, but as a star offensive lineman in his youth, he was famous for pancake blocks—-those that flatten the opponent. Pancake actually does work for Ray. He possesses crazy computer skills but also knows how to handle almost any confrontation. Ray, Pancake, and Nicole have a knack for ensnaring Jake in things he wants no part of. Therein lies the comedy.

My new Cain/Harper series features Bobby Cain and Harper McCoy, a non-biologic brother-sister team. They grew up in an itinerate, criminal “family” that traveled throughout the Southeast living off the land, doing odd jobs like construction and landscaping, and putting on shows where dancing, singing, skits, and the sale of homemade trinkets helped pay the bills. But the family also runs scams and steals. Bobby came to the group at two months of age when he was scooped up from a Houston bus station where he had been abandoned by his mother. Harper, a year older than Bobby, was purchased from her alcoholic, half-Cherokee mother for $200 and a couple of bottles of whiskey. They were raised by the family, but mostly by the couple known as Uncle Al and Aunt Dixie.

Bobby was given his first knife at age four, and quickly became a master of the weapon. Mainly throwing. By age seven, he was known as Bobby Blade and was the star of the family’s shows. Harper was often the target, as she held balloons, coins, and even spun on a wheel while Bobby hurled blades her way. Bobby was also trained in hunting and in second-story home invasions. He could get into and out of almost anywhere without being detected. Even occupied homes while the owners slept.

Harper was a natural scam artist. She could play almost any role, cry on cue, and pick your pocket, or purse, while you were looking right in her sobbing face.

When Bobby was 12, Harper 13, the FBI took down the family with a handful of warrants from a half a dozen states. Bobby and Harper were adopted by separate families and lost contact for 15 years. Until their paths crossed, during a back ops mission, on the other side of the world. Harper was with the CIA and was running the op. Cain, a skilled assassin who employed his B&E and knife skills to perform missions that don’t exist, was brought in at the last minute after the mission morphed into something requiring his special brand of stealth.

They both left military work shortly afterward and are currently private contract fixers. Like P.I.s only much more. They make a formidable team. They are smart, tough, skilled, and not shy about dispensing bodily harm when necessary. In their first adventure (SKIN IN THE GAME), they are tasked with locating a missing Vanderbilt University co-ed who is the granddaughter of a retired Air Force General. This leads them to a small, lake-side Tennessee town and into the world of a dark and deranged killer.

I think the great variability in characters who are private investigators makes for great stories. And as a writer, excellent fodder for character creation and storytelling. It’s why I read P.I. novels and why I write them. As do many of my fellow authors.

 
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Posted by on January 7, 2020 in Writing

 

A-LIST is a January 2020 Kindle Monthly Deal

 

 

A-List, the 2nd Jake Longly comedic thriller (after DEEP SIX), is available as a Kindle Monthly deal throughout January. Only $1.99. Join Jake, Nicole, Pancake, and Ray as they visit the Big Easy to unravel a sordid and confusing murder.

Jake Longly and girlfriend Nicole head to New Orleans after Nicole’s producer/uncle Charles Balfour’s mega-star, A-list actor Kirk Ford, awakens with a dead co-ed in his hotel bed. Worse, the girl is the niece of local mafioso Tony Guidry.

But something isn’t right. The facts don’t fit. Who would want Kristi Guidry dead, or Kirk framed? And why?

Nothing’s easy in the Big Easy

Buy Now: https://www.amazon.com/List-Jake-Longly-Book-ebook/dp/B076N2ZC95/

Details: http://www.dplylemd.com/book-details/a-list.html

 
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Posted by on January 3, 2020 in Writing

 
 
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