John H. Trestrail III, BS Pharm, FAACT, DABAT-E

Forensic & Clinical Toxicologist

ConsultantAuthor - Speaker


For Consultations and Speaking Engagments, contact

Seminars & Presentations


“Poisoners Throughout History”
A entertaining and educational discussion of homicidal poisoning from the days of early man, down to the present, with case discussions of real poisoners drawn from criminal history.  (1.5 hour presentation)

“Murder by Poison!”
A forensic workshop intended for law enforcement, toxicologists, forensic scientists, & attorneys, which discusses in depth, what is known to date about the homicidal poisoner.  NOTE: This seminar is not available to the general public.

Topics discussed include:

  • Poisons as Weapons, The Poisoner, The Victim
  • The Crime Scene Investigation, Proving the Poisoning Crime, Poisoning Homicide Epidemiology
  • Putting the Poisoner on Trial

(2.5 hr presentation)

“The 1910 Poisoner Case of Hawley Harvey Crippen, MD, London, England, and its Many Unanswered Questions”
Poisoning murder! Dismemberment! Flight from justice!
For its time, this 1910 London poisoning murder, was the “case of the Century”, and remains the most famous case in murder investigation, second only to “Jack-the-Ripper”. The audience will be placed on a "mock-jury" for the presentation, and asked to vote at the end of the presentation.  Our presentation will cover the pathology, analytical toxicology, forensic investigations, and trial events that were involved in the resulting prosecution of Coldwater, Michigan, born, Dr. Hawley Harvey Crippen, that ultimately lead to his execution for the poisoning murder of his wife. Also covered, will be the speaker’s work in London, and involvement with British researchers, that are attempting to answer some of the many questions, which seem to indicate there are many more mysteries to this case than anyone ever realized! (2.5 hr presentation)

“Toxicomania: A Madness for Poisons - a Review of the Case of Graham Frederick Young”
A discussion of the unique poisoner case that involves the condition of unusual condition of “toxicomania”, or madness for poisons. Discussed will be the background, and criminal psychology of this unique homicidal poisoner.  (60 min presentation)

“Agents of Chemical & Biological Warfare & Terrorism”
A history of chemical and biological warfare and terrorism from ancient times to the present, along with the advantages and disadvantages of these types of agents.  (90 min presentation)


“Larger Than Life! Matinee Monsters and Poison Perils: How the Horror Movies of the 1950s, Influenced a Generation”
A discussion of the social-psychology of the 1950s, and how the portrayal of venomous animals in the science-fiction films of the time possibly influenced how the general population viewed their natural surroundings. Clips of films will be shown along with a discussion of the comparison of what was portrayed vs. the reality of nature’s toxicology.  (1hr presentation )

“Famous Toxicologists: A Graveyard Tour”
Toxicology as we know it today, truly rests upon the shoulders of giants! This presentation covers the lives and accomplishments of some of our now deceased great pioneering toxicologists, and takes us on a worldwide visual tour to visit their final resting places. (45 min presentation)

“Antidotes in Toxicology”
A discussion of the history of antidotes for poisons, including, investigational antidotes now being studied, and the proper utilization of drugs under IND status. Topics covered include: what is an antidote, antidotes in ancient times, antidotes in modern times, mechanisms of action of the more commonly used antidotes, investigational antidotes, foreign antidotes, & requirements for utilization of investigational drugs. (60 min presentation)

“Nature's Toxic Agents: A Menagerie of Critters” A discussion of the toxicology and treatment for envenomation by: stinging insects, spiders, scorpions, and miscellaneous venomous animals: lizards, amphibians (toads, frogs, & salamanders), some exotic venomous mammals (platypus, shrews, & solendons), & a discussion of the newly discovered toxic birds. (120 minute presentation)

“Marine Toxicology”
A discussion of the toxicology and treatment for those toxic creatures encountered in the marine environment. Topics discussed include: shellfish poisoning, coelenterates, echinoderms, molluscs, ciguatoxic fish, scrobrotoxic fish, tetrodotoxic fish, venomous fish, & sea snakes. (60 minute presentation)

“Safer Mushroom Hunting for Beginners!”
An introductory discussion of the basics of safer mushroom collecting for the beginner amateur mushroom hunter to concentrate on, so as to avoid toxicological problems. Includes a discussion of the “safe six” mushrooms to collect: “Morels”, “Puff Balls”, “Sulfur Shelves”, “Shaggy Manes”, “Oyster Mushrooms”, & “Hen-of-the-Woods”. (60 minute presentation)

“An Introduction to Morel Hunting”
An introductory discussion of the basics of collecting the choice mushrooms known as “Morels” (Morchella), as well as the avoiding of the collecting and consumption of the “False Morel” (Gyromitra spp.). (60 minute presentation)

“Mushroom Toxicology”
An discussion of the chemistry of the toxic compounds found in the mushroom world, along with their epidemiology, pharmacology & toxicology, clinical effects, and treatment of the mushroom exposed patient. Included are methods for a systematic approach for the general diagnosis and management of any patient exposed to poisonous mushrooms. (90 minute presentation)

“Mushroom Identification: With Eye & Microscope”
An extensive discussion of identification techniques used to identify mushrooms in the field, as well as the laboratory, using the eye, microscopes, and chemical methods. (90 minute presentation)