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What is the Toxicology Report?

Jul 15, 2013 | Education | 0 comments

When does an element change from being a remedy to being a poison? 

A toxicology report can give you clues.

So many herbs, elements, medications and chemicals can be used in advantageous was to help heal, clean, and improve our lives. We have heard so many stories of substances that once were used to help, when taken in a different direction, can cause harm or even death.

As a nurse, when you hear about a Toxicology Report, the first thing you might think of is the Tox Screen we do in the hospital to test for legal or illegal drugs that may be a contributing factor to a patient’s diagnosis and symptoms.  It is, however, so much more.  Toxicology information affects not only healthcare, but our homes, workplaces, food and earth environments.  Toxicology principles have been recognized historically ever since humans used herbs for medicine.

FromToxicology Education Foundation: Toxicology Tutor I:  Basic Principles:

” The traditional definition of toxicology is “the science of poisons.”  As our understanding of how various agents can cause harm to humans and other organisms, a more descriptive definition of toxicologyis  “the study of the adverse effects of chemicals or physical agents on living organisms”.”

These adverse effects may occur in many forms, ranging from immediate death to subtle changes not realized until months or years later.  They may occur at various levels within the body, such as an organ, a type of cell, or a specific biochemical.  Knowledge of how toxic agents damage the body has progressed along with medical knowledge.  It is now known that various observable changes in anatomy or body functions actually result from previously unrecognized changes in specific biochemicals in the body.

The historical development of toxicology began with early cave dwellers who recognized poisonous plants and animals and used their extracts for hunting or in warfare.  By 1500 BC, written recordings indicated that hemlock, opium, arrow poisons, and certain metals were used to poison enemies or for state executions.

With time, poisons became widely used and with great sophistication.  Notable poisoning victims include Socrates, Cleopatra, and Claudius.   By the time of the Renaissance and Age of Enlightenment, certain concepts fundamental to toxicology began to take shape.  Noteworthy in this regard were the studies of Paracelsus (~1500AD) and Orfila (~1800 AD).

Paracelsus determined that specific chemicals were actually responsible for the toxicity of a plant or animal poison.  He also documented that the body’s response to those chemicals depended on the dose received.  His studies revealed that small doses of a substance might be harmless or beneficial whereas larger doses could be toxic.  This is now known as the dose-response relationship, a major concept of toxicology.  Paracelsus is often quoted for his statement:  “All substances are poisons; there is none which is not a poison.  The right dose differentiates a poison and a remedy.”

Orfila, a Spanish physician, is often referred to as the founder of toxicology.  It was Orfila who first prepared a systematic correlation between the chemical and biological properties of poisons of the time.  He demonstrated effects of poisons on specific organs by analyzing autopsy materials for poisons and their associated tissue damage.

The 20th century is marked by an advanced level of understanding of toxicology.  DNA (the molecule of life) and various biochemicals that maintain body functions were discovered.  Our level of knowledge of toxic effects on organs and cells is now being revealed at the molecular level.  It is recognized that virtually all toxic effects are caused by changes in specific cellular molecules and biochemicals.

Xenobiotic is the general term that is used for a foreignsubstance taken into the body.  It is derived from the Greek term xeno which means “foreigner.”  Xenobiotics may produce beneficial effects (such as a pharmaceuticals) or they may be toxic (such as lead).

As Paracelsus proposed centuries ago, dose differentiates whether a substance will be a remedy or a poison.  A xenobiotic in small amounts may be non-toxic and even beneficial but when the dose is increased, toxic and lethal effects may result.

Some examples that illustrate this concept are:


A toxicology screen refers to various tests that determine the TYPE and APPROXIMATE AMOUNT of legal and illegal drugs a person has taken.  It can be used to determine multiple cause/effect of multiple substance related problems including accidental or intentional overdoses of polypharmacy, drug use, drug abuse and poisoning.

Additional testing reasons include:  Alcoholism, Alcohol withdrawal, Altered mental status, Analgesic nephropathy [kidney poisoning], Delirium tremens, Delirium, Dementia, Fetal alcohol syndrome, Seizures, Stroke secondary to drugs,  Suspected sexual assault and Unconsciousness.

Toxicology screening is recommended to be completed as soon after taking the substance or presentation of the patient as possible.  Testing can be done using blood, urine or stomach contents.

IF THE TEST IS USED AS A DRUG SCREEN, IT MUST BE DONE IN A CERTAIN PERIOD OF TIME after the drug has been taken and while it can be detected:

  • Alcohol: 3 to 10 hours
  • Amphetamines: 24 to 48 hours
  • Barbiturates: up to 6 weeks
  • Benzodiazepines: up to 6 weeks with high level use
  • Cocaine: 2 to 4 days; up to 10 to 22 days with heavy use
  • Codeine: 1 to 2 days
  • Heroin: 1 to 2 days
  • Hydromorphone: 1 to 2 days
  • Methadone: 2 to 3 days
  • Morphine: 1 to 2 days
  • Phencyclidine (PCP): 1 to 8 days
  • Propoxyphene: 6 to 48 hours
  • Tetrahydrocannabinol (THC): 6 to 11 weeks with heavy use


  • Alcohol (ethanol) — “drinking” alcohol
  • Amphetamines
  • Antidepressants
  • Barbiturates and hypnotics
  • Benzodiazepines
  • Cocaine
  • Flunitrazepam (Rohypnol)
  • Gamma hydroxybutyrate (GHB)
  • Marijuana
  • Narcotics
  • Non-narcotic pain medicines including acetaminophen and anti-inflammatory drugs
  • PCP
  • Phenothiazines (antipsychotic or tranquilizing medications)
  • Prescription medications, any type

Be aware, that special consents may be required for testing certain substances or testing minors.

PLAY AND LEARN!  Try them!  They are fun AND educational!!




TOX TOWN: Learn about chemicals where you live, work and play











These are really interesting programs developed and funded by The Toxicology and Environmental Health Information Program of the National Library of Medicine, U.S. Department of Health and Human Services.

Toxicology Tutor I: Basic Principles

Toxicology Tutor II:  Toxicokinetics

Toxicology Tutor III: Cellular Toxicology


Toxicology Education Foundation Resources;  a comprehensive list of resources from the NLM/NIH.

Centers for Disease Control and Prevention

Consumer Product Safety Commission

Environmental Health & Toxicology Health Program:  Includes information about toxicology and environmental health.  Includes TOXNET toxicology database.

Environmental Protection Agency

National Institute of Health

National Institute for Occupational Safety and Health

National Library of Health

Pillbox:  Ways to identify unknown pills

Toxicology Screen

TOXNET:  Collection of databases on hazardous chemicals, toxic releases and environmental health.  Includes information regarding chemicals and lactation and, household products.

US Department of Agriculture



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