Science of Toxicology

Expanding Its Niche in Modern Health Care

This article originally appeared in Pathways, a magazine published for physicians and the community by UMass Memorial Medical Center.

The science of toxicology traces its roots to those early cave dwellers who were the first to discover the abundance of poisons in the natural world. Through what must have been catastrophic episodes of trial and error, our ancestors learned how to extract lethal poisons from local flora and fauna to better hunt and defend against invaders.

Later, humankind evolved to discover that toxic substances found in nature could be used for purely evil purposes, such as the tragic events that took the lives of Socrates (henbane), Cleopatra (snake venom) and Claudius (mushrooms). The 16th century produced many free thinkers, including a notable Swiss alchemist named Paracelsus, who recorded that "All substances are poisons; there is none which is not a poison. The right dose differentiates a poison from a remedy."

Known as the father of toxicology, Paracelsus discovered that all substances are poisons if exposure and absorption are excessive. At very low doses, even the most toxic chemicals will cause no noticeable side effect on humans, while at very high doses, essential substances like salt, oxygen and water will potentially cause adverse effects ranging from sudden death to subtle changes not immediately realized.

Fortunately, knowledge of how toxins damage the body has paralleled the changing world of modern medicine. As we entered the 21st century, today's toxicologists are benefiting from recent advancement in DNA and protein research that explains toxic effects at the molecular level. In fact, an emerging field known as toxicogenomics combines genomics and bioinformatics to identify and characterize mechanisms of toxicity of compounds. It is now well established that virtually all toxic effects are caused by changes in specific cellular molecules and biochemicals.

Locally, the Division of Toxicology at UMass Memorial Medical Center provides a broad range of consultation services for the management of the critically ill, poisoned patient. The seven-member division, comprised of physicians and toxicology specialists, provides management recommendations for an average of four UMass Memorial Emergency Department (ED) patients per day. The group also provides as many as 15 daily telephone consults to EDs throughout New England.

"A medical toxicologist is on call around the clock, and we welcome consultation requests from all physicians and health care professionals," said Edward Boyer, MD, PhD, chief of the division. "We accept the transfer of acutely poisoned patients from other hospital emergency departments, facilitated through a single phone call to our Life Flight air ambulance service."

Staff members in toxicology provide many additional clinical and informational resources. The division's attending physicians assist clinicians in identifying and managing unanticipated adverse drug events. They also offer pharmacokinetic analysis of patients with comorbid illness requiring multiple drug therapy in order to avoid unanticipated drug interaction.

On an outpatient basis, the Toxicology Division performs independent medical evaluations of individuals who believe they were exposed to environmental or occupational toxins. UMass Memorial toxicologists are recognized throughout New England for expertise in assessing exposures to chemicals in the workplace and provide consultation services to the Agency for Toxic Substances and Disease Registry, and the Centers for Disease Control.

As a result of current global unrest following the events of September 11, 2001, UMass Memorial medical toxicologists are fully trained and equipped to provide expert consultation for all forms of chemical terrorism. In addition, the division serves as a key resource for first responders in Central Massachusetts by assessing hazardous materials exposures. The division's clinical activities in this area are augmented by staff member Steven Bird, MD, who studies the mechanisms of toxicity of organophosphates, a class of chemicals that are potent chemical weapons.

The staff is currently involved in several clinical studies, including a National Institutes of Health funded project to assess the relationship between the Internet and illicit drug usage, a project that has garnered national attention and numerous network television appearances for Dr. Boyer, the study's principal investigator.

While the Internet has forever changed the way commerce is conducted around the globe, those profiting from this powerful business enabler include merchants of illegal drugs. As drug wheelers and dealers go high-tech, increased numbers of children and teens are turning on by simply turning on their PCs.

Another problem facing toxicologists is the emergence of drugs that are being used with other substances to produce specific neurobehavioral effects. Under a presumption of legality, these items can be easily purchased from retail outlets. "The number of patients who present in the ED for medical care following use of these substances is low, but the increase is identified from our investigations and patient interviews," said Dr. Boyer.

Currently, Dr. Boyer is the principal investigator for a research project to study "club" drugs, so-called because popular usage occurs in nightclubs and other entertainment venues. In recent years, this class of drugs has gained popularity among teens and young adults. Dr. Boyer pointed out that the availability of stronger drugs is producing immediate toxicity, as well as long-term effects.

"Ecstasy, GHB and ketamine are responsible for significant morbidity and mortality," commented Dr. Boyer. "Also, over-the-counter medications such as dextromethorphan are popular recreational drugs and are especially common among 12 to 15-year-olds. Abuse of pharmaceuticals like dextromethorphan may be responsible for promoting significant illicit drug use in later years with attendant health risks."

What is clear is that the diligence of today's ED toxicologists in studying current drug use is yielding important trend data on emerging patterns and the health consequences of substance abuse in the United States.

According to Greg Volturo, MD, chair, Department of Emergency Medicine, "Our Emergency Department has the ability to care for a wide variety of toxicologic emergencies utilizing the expertise of our toxicologists and specialists from many departments, including emergency medicine, pediatrics, pharmacy, nephrology and others. We are filling a significant health care need in Central New England by providing a well-balanced toxicology consultation service to improve the quality of care for those with potentially toxic exposures, including prescribed medications, occupational and environmental concerns and widespread drug abuse."