Posted: 3/19/2018
Parkland toxicologist shares love of toxicology during Poison Prevention Week
As any fan of Agatha Christie novels can attest, it pays to know your poisons. From absinthe to arsenic to agent orange, toxic substances have helped shape the course of human history – not just in murder mysteries, but also in warfare, politics, medicine, agriculture, manufacturing and every aspect of human affairs, including romantic ones, throughout the ages.
“Toxicology fascinates me,” said Sarah Shafer, MD, who is completing fellowship training in the specialty at Parkland Health & Hospital System and UT Southwestern Medical Center. “I joke that I’m an evangelist for toxicology, because literally everything is related to this field. The history of toxicology is in many ways the history of humanity.”
During National Poison Prevention Week, March 20-26, Dr. Shafer and other specialists at the North Texas Poison Center (NTPC) at Parkland want to raise awareness and reduce the incidence of unintentional poisonings, whether from accidental overdoses of Tylenol or street drugs.
“We’re surrounded by deadly substances in our homes, cars, gardens, at school and at work,” Dr. Shafer said. “It’s a dangerous world and we need to know how to protect ourselves and our families from the hazards under our sinks and in our medicine chests.”
But she also loves to share her passion for her profession, which was sparked during a residency rotation at Bellevue Hospital in New York. “I was attending a lecture about beta blockers and something clicked for me. A toxicologist was explaining how these drugs affect the disease process and can fix the problem. It was like getting under the hood of medicine a bit and it opened me to the idea of doing a fellowship in toxicology.”
Although she’s more drawn to cellular biology than history, Dr. Shafer enjoys relating her “favorite factoids” from the annals of toxicology. “Toxicology is part of our everyday lives and affects each of us in countless ways. Before there were medicines, people were experimenting with plants and minerals and coming up with new uses for them.”
For example, she says, think about the poison darts used by primitive hunters to disable their prey. “Curare is a toxin derived from jungle plants that people boiled down into a thick black compound and then dipped their darts into. It causes muscle paralysis, but only by injection, not when it’s eaten. We use curare every day in hospitals as a muscle paralytic for patients before surgery or intubation or to create a medically-induced coma,” she said.
In 2017, Dr. Shafer won a competition at the national conference of American College of Medical Toxicology with a presentation titled “The Unholy Trinity: Satan, Santa Claus, and Nickel.” She will compete again this year with a presentation called “Alchemy Realized,” tracing the discovery of chemical synthesis in the mid-1800s that led to the development of pharmaceutical chemistry.
“Although we’ve never realized how to turn lead into gold, we have discovered how to turn coal tar, used by the pharmaceutical industry as a base for countless medications, into a multi-billion dollar enterprise that far exceeds the annual revenue of the gold mining industry,” she said.
In antiquity, the Chinese, Egyptians, Sumerians, Greeks and Romans experimented with poisons and antidotes. These early scientists tested chemicals, herbs and potions on themselves and prisoners. Shen Nung, known as the Father of Chinese medicine, died of a toxic overdose of an herb in the 27th century BC. Socrates and Cleopatra both chose poisons to end their own lives - he by drinking hemlock and she by the lethal bite of an Egyptian asp.
Catherine of Medici, Queen of France in the 1500s, was known as an expert assassin who tested poisons on the unsuspecting poor and sick, along with her political rivals. It’s believed she used a pair of poisoned leather gloves to rid herself of an enemy.
In 1250 the Dominican friar Albertus Magnus discovered arsenic, a lethal substance favored by murderers real and fictional, from Chaucer to Sir Arthur Conan Doyle, Dame Agatha, Dorothy Sayers, Dashiell Hammett, Rex Stout and American playwright Joseph Kesselring in his ever-popular comic play “Arsenic and Old Lace.”
“Most people don’t think much about poisons, but they should,” Dr. Shafer said. “The best way to prevent accidental poisoning is to learn more about the everyday substances in our lives that can be poisonous and to know the risks. The Poison Control Center is here to help people 24/7 if a poisoning happens. But what we most want to do is help people reduce their risk before a poison emergency occurs.”
Experimental drug use and other risky behaviors by teens, like the current fad of consuming laundry detergent pods, are major concerns for toxicologists, she said. “The most dangerous trend we see now is the addition of fentanyl to opioids on the market. These products have no regulation, labeling, quality or potency controls. People think its heroin, but they don’t know what they’re getting. It’s a wild card and it’s extremely risky.”
Dosage is often the key when dealing with potentially lethal substances that may have beneficial effects when used in small amounts. Paracelsus (1493–1541) is credited with the classic toxicology maxim, “All things are poisonous and nothing is without poison; only the dose makes a thing not poisonous.” Simply put: “The dose makes the poison.”
One of the strangest questions Dr. Shafer had from a caller seeking help from the NTPC was whether a sloth bite was venomous. “I had to look it up, but it turns out the bite is not poisonous. However, I told the caller to watch out for possible infection.”
One of the most common overdoses reported to Poison Centers across the U.S. is acetaminophen, she said. “It’s also the number one cause of acute liver failure in the United States. As little as two additional extra strength pills a day, just 25 percent above the maximum daily dose, taken over several days, can cause liver damage and less than four times the maximum daily dose can cause death.”
From dare-devil laundry pod challenges to accidental snake bites or drug overdoses, the potential for poisoning is ever-present. Fortunately the NTPC offers free access to healthcare advice to both the lay public and healthcare providers in need of expert assistance via a toll-free 24-hour line to a network of nurses, pharmacists, paramedics and physicians who are specialists in toxicology. If you have a poison emergency or question, call the Poison Help Line at 1-800-222-1222.
And if you want to learn more about toxicology, Dr. Shafer recommends it as both a hobby and a career. “Human ingenuity is amazing. You can see the traces of science fiction fantasies in our modern technology and toxicology.”
For more information about Parkland, please visit www.parklandhospital.com