Forensics For Dummies Updated 2nd Edition is now available.
Get it through your local Indie Bookstore or here:
Forensics For Dummies Updated 2nd Edition is now available.
Get it through your local Indie Bookstore or here:
Just got the new cover for Forensics For Dummies, 2nd Edition.
It will be released from Wiley on 2-29-16
Bad air will kill you. One form of bad air is Sewer Gas. It’s a combination of hydrogen sulfide, methane, ammonia, and carbon dioxide. If you enter a sewer or manure pit or some area where these gases are concentrated, you can be a goner is short order. Breathing this combination of gases can kill, and can do so quickly.
This is what happened to Iowa hog farmers Gene and Austin Opheim. Austin went into the manure pit to salvage a piece of equipment that had fallen in, but he was quickly overcome by the gas. HIs father, Gene followed, trying to save his son, but he too fell victim to this treacherous gas.
FROM HOWDUNNIT: FORENSICS:
Hydrogen sulfide is a byproduct of fermentation and is often found in sewers and cesspools. The combination of the two toxic gases hydrogen sulfide and carbon monoxide and the suffocating gas methane is called sewer gas. When inhaled or ingested, hydrogen sulfide converts oxyhemoglobin (hemoglobin rich in oxygen) into methemoglobin, which does not release oxygen to the tissues, thus effectively suffocating the cells of the body. Methemoglobin imparts a dark purple color to the blood, which can be seen at autopsy, where the ME is also likely to fi nd high levels of sulfide in the blood of sewer gas victims. These deaths are almost always accidental and occur when the victim enters an area rich in sewer gas.
You would think that the last thing that an astronaut would fear while performing a spacewalk would be drowning. How on earth does that happen? Oh, wait a minute, he wouldn’t be on Earth. I guess out there in the wild blue yonder all the rules change. Ask Luca Parmitano, an Italian astronaut who worked on board the International Space Station (ISS). It seems that over a liter of water accumulated inside his helmet obstructing his ears and his eyes and raising the possibility that he could drown in space.
He isn’t the only one to suffer spacesuit problems during spacewalks, Extravehicular Activities or EVAs in NASA-speak. Here is an interesting article from The New Scientist on five such situations.
Q: I have two characters who are found dead in their house, having been at the center of a fire that turned into a wildfire. Before the fire, a hitman gave them some type of medication that he believed would not be detected in an autopsy to cause them to go unconscious or unable to move while he set the fire around them and escaped. The idea is that I want it to look — on the outside, at least — as though they accidentally caused the wildfire, starting in their home in the forest. Then, it’s discovered that they were, technically, murdered by someone giving them a strong sedative (or something) and they were burned in the fire.
When the medical examiner does the autopsy, what is he likely to be able to notice? I read that bodies are usually not burned completely in a fire, but what would the ME find? What kinds of things would he notice and talk about in the report?
Is there a drug that would have a sedative effect on the characters that would NOT show up in an autopsy? Or something that might show up with a particular test and what reasons could an ME have to run that test?
Kari Wolfe, Colorado Springs, CO
A: You are correct that fires rarely destroy a body completely. The fire simply does not burn hot enough or long enough to completely destroy the body in most structure and automobile fires. The same would hold for wildfires. The body would likely be charged severely on the outside and for several inches down but deep inside most tissues would remain intact. This would allow the medical examiner to test the muscles, brain tissue, liver, blood, bone marrow, urine, and the vitreous humor inside the eyes for various drugs.
Almost any narcotic or sedative would work for your purposes but most of these are easily found with even simple toxicological screening and for sure by more sophisticated toxicological testing using gas chromatography and mass spectroscopy.
More sophisticated drugs are not revealed by a routine drug screen and therefore more difficult to find. Add to this the fact that the medical examiner might have no reason to go to the time and expense of looking for more esoteric toxins if all evidence pointed to the victim having died in the fire.
But what if the victim didn’t die in the fire? What if the victim was already dead before the fire started? This would change everything since in that case the medical examiner could not say that the cause of death was asphyxia from the fire but rather that something else must have killed the victim. In the absence of overt trauma or another obvious cause of death, the ME would likely do more complete toxicological testing.
How would the ME determine that the victim was dead before the fire? One clue would be the carbon monoxide level in the blood. If this is low, the victim was not breathing while the fire was consuming him. If the carbon monoxide level was high it would indicate that he was breathing and had inhaled carbon monoxide, which comes from the burning of wood and almost any other product. The normal carbon monoxide level is less than 5% but in victims of fire it can be 60 to 90%.
Also, if the victim was still breathing during the fire he would inhale soot and heat. The heat would damage the throat and airways and soot and other fire debris would be inhaled deeply into the lungs. Finding these would indicate the victim was alive while the fire burned and not finding them would suggest a prior death. This latter situation could launch a more complete toxicological analysis of the remains and ultimately lead to the lethal drug. Such testing could take many weeks, even months, so that you can delay the discovery of the true cause of death for almost as long as you need for story purposes.
Q: Here’s my book situation: A man puts a plastic bag over his head to kill himself. His wife wakes up next to him (after he nearly strangled her to death and she discovers he’s killed their son) and in her horror and rage cracks him over the head with a blunt object.
Here’s my question: Can the police/coroner/forensics determine which was the cause of death–suffocation or blunt force trauma? If so, what would the signs be pointing to asphyxiation? Also, if it matters, this is set in 1969.
Judy Merrill Larsen, author of All the Numbers
A: If the victim died first from the asphyxia, the ME would have no problem since the blow to the head would cause no bruising or bleeding. At death the heart stops and blood flow ceases and a corpse will not bleed or bruise easily. So the ME would see a mark where the victim was struck but no bleeding or bruising and know that the blow was delivered post-mortem.
If he was still alive when struck, things become a little more difficult for the ME but he should still be able to tell. Bruising and bleeding at the site of the blunt trauma would show that the victim was alive when struck but if there is no significant brain injury found at autopsy he would know that the force of the blow did not cause death and the asphyxia must have. If there is a brain injury such as cerebral contusion (brain bruise) or bleeding into or around the brain, he might have difficulty determining the actual cause of death. Of course any evidence of blunt trauma would point to homicide and not suicide since someone using a plastic bag for suicide would not likely also strike themselves in the head.
But I see a bigger problem with your scenario. If she was unconscious from being strangled, she would wake up within 10 seconds to a minute or so after the pressure was released unless she had significant brain injury from lack of oxygen. If she were simply strangled into unconsciousness, which is due to blocking blood flow thru the carotid arteries to the brain and not blocking breathing, as soon as the pressure was released and blood flow reestablished, she would wake up very quickly. Much sooner than he could put a bag on his head and die from asphyxia. For her to be out that long would require some degree of brain injury and I don’t think that’s what you want. Of course, if he drugged her first and then strangled her to the point he thought she was dead, but she in fact wasn’t, then she would awaken when the drug effect wore off. Here he could be dead for hours before she awakened.
From HOWDUNNIT: FORENSICS: When more than one person is found dead in a house or a car and there is no evidence of trauma, carbon monoxide toxicity is considered. The odds of two or more people dying from natural causes at the same time and the same place are extremely remote.
Such is the case of “Buckwild” star Shane Gandee who was found dead, along with two other men, in a vehicle partially submerged in mud. The supposition is that mud clogged the vehicle’s tail pipe and this allowed carbon monoxide (CO) to accumulate inside the passenger compartment, resulting is death from asphyxia.
When I first read the circumstances surrounding this tragedy, my first thought was CO. With no signs of trauma, little else made sense. Apparently the authorities have agreed that this was the cause of death.
Also from HOWDUNNIT: FORENSICS: CHAPTER 8: ASPHYXIA
Deaths from carbon monoxide poisoning are usually suicidal or accidental. It is an uncommon method for homicide, but it has been reported. Carbon monoxide is stealthy, treacherous, deadly, and common. A family is found dead and the cause is a faulty heater or fireplace. A suicide victim is found in his garage with the car engine running. Campers are found dead in a tent, a kerosene lantern burning in one corner. Each of these is due to carbon monoxide poisoning.
Carbon monoxide is a tasteless, odorless, colorless gas that is completely undetectable by humans. It results from the incomplete combustion of carbon-containing fuels—paper, wood, gasoline, and many other combustible products. Complete combustion of one of these fuels yields carbon dioxide (CO2). If there is a deficiency of oxygen or if the fi re is smoldering and doesn’t produce enough heat to drive the reaction to completion, incomplete combustion occurs and the result is the production of carbon monoxide.
Wood, coal, and gas are common carbon-containing fuels. Faulty stoves,heaters, and fireplaces, as well as the exhaust from a car engine, can fill the air with carbon monoxide. Carbon monoxide poisoning is a more common cause of death in fires than is the fire itself. Charcoal briquettes are particularly dangerous as they are designed to smolder rather than burst into flame and are also good sources for carbon monoxide. Using a charcoal grill in an enclosed space such as a garage or tent can lead to carbon monoxide buildup very quickly. Faulty butane and propane camp stoves and heaters can also be deadly.
Carbon monoxide’s treachery lies in its great affinity for hemoglobin, the oxygen-carrying molecule within our red blood cells (RBCs). When inhaled, CO binds to hemoglobin producing carboxyhemoglobin. It does so three hundred times more readily than does oxygen, and thus it displaces oxygen. The result is that the blood that leaves the lungs and heads toward the body is rich in carbon monoxide (carboxyhemoglobin) and poor in oxygen (oxyhemaglobin).
This strong affinity of hemoglobin for carbon monoxide means that very high blood levels can occur by breathing air that contains only small amounts of carbon monoxide. For example, breathing air that contains a carbon monoxide level as low as 0.2 percent may lead to blood carbon monoxide saturations greater than 60 percent after only thirty to forty-five minutes. So, a faulty heater or smoldering fi re that produces only a small amount of carbon monoxide becomes increasingly deadly with each passing minute.
This powerful attraction for hemoglobin explains how certain individuals succumb to carbon monoxide poisoning in open areas. Most people believe that carbon monoxide is only toxic if it is in an enclosed area, but this is not true. There have been cases of individuals dying while working on their cars in an open area, such as a driveway. Typically the victim is found lying near the car’s exhaust. Similarly, the newly recognized problem of carbon monoxide poisoning in swimmers and water skiers who loiter near a dive platform on the back of a powerboat with an idling engine.
The degree of exposure to carbon monoxide is typically measured by determining the percent of the hemoglobin that is carboxyhemoglobin. The signs and symptoms of carbon monoxide toxicity correlate with these levels. The normal level is 1 to 3 percent, but may be as high as 7 to 10 percent in smokers. At levels of 10 to 20 percent, headache and a poor ability to concentrate on complex tasks occur. Between 30 and 40 percent, headaches become severe and throbbing, and nausea, vomiting, faintness, and lethargy appear. Pulse and breathing rates increase noticeably. Between 40 and 60 percent the victim becomes confused, disoriented, and weak, and displays extremely poor coordination. Above 60 percent, coma and death are likely. These are general ranges since the actual effect of rising carbon monoxide levels varies from person to person. In the elderly and those with heart or lung disease, levels as low as 20 percent may be lethal. Victims of car exhaust suicide or those who die from fire in an enclosed room may reach 90 percent.
A running car engine in an enclosed garage is a common method for suicide, but it could also be used for homicide. If the killer subdues the victim by force or by way of intoxication, he could place the victim in his car and let the carbon monoxide actually do him in. When determining the manner of death, the ME looks for evidence of trauma to the victim as well as performs a toxicology screen. Finding trauma, such as evidence of a blow to the head, might change the manner of death from suicide to homicide, but finding drugs may not. Some people use multiple suicide methods to assure success and a drug overdose combined with carbon monoxide inhalation is not rare.
When more than one person is found dead in a house or a car and there is no evidence of trauma, carbon monoxide toxicity is considered. The odds of two or more people dying from natural causes at the same time and the same place are extremely remote.
Carboxyhemoglobin is bright red in color and imparts this hue to the blood. When the ME performs an autopsy and sees bright cherry-red blood, he suspects carbon monoxide poisoning as the cause of death. This finding is not absolutely conclusive since cyanide inhalation or ingestion can also result in bright cherry-red blood and tissues. Also, individuals dying from cold exposure or corpses exposed to very low temperatures may show bright red blood.
Livor mortis in these situations may also be red or pink rather than the usual blue-gray color (see Chapter Five: Time of Death, “Livor Mortis”).
At autopsy, the internal organs in victims of carbon monoxide intoxication are also bright red. Interestingly, this color does not fade with embalming or when samples taken by the ME are fixed in formaldehyde as part of the preparation of microscopic slides. At times the presence of carbon monoxide can be found in the blood as long as six months after death.
Individuals who survive carbon monoxide intoxication may have serious long-term health problems. The brain is particularly vulnerable since it is extremely sensitive to lack of oxygen. Symptoms and signs of brain injury can begin immediately or be delayed for several days or weeks. The most common aftereffects include chronic headaches, memory loss, blindness, confusion, disorientation, poor coordination, and hallucinations. The ME may be asked to evaluate a living victim in this situation if the exposure was due to a criminal act or if a civil lawsuit is involved.