Lecture 1: Toxicology I Flashcards
List the Halogenated Hydrocarbons that can cause intoxication
- Carbon tetrachloride (CCl4)
- Chloroform (CHCl3)
List the Aromatic Hydrocarbons that can cause intoxication
- Benzene
- Toluene
List the Alcohols that cause intoxication
- Methanol
- Ethylene glycol
List the Pesticides that cause intoxication
- Organophosphates
- Carbamates
- Pyrethroids
- Rotenone
List the Rodenticides that cause intoxication
- Brodifacoum
- Difenacoum
List the Metals that cause intoxication (6)
- Lead (Pb)
- Mercury (Hg)
- Cadmium (Cd)
- Arsenic (As)
- Iron (Fe)
- Copper (Cu)
List all the Antidotes and Treatments that treat different intoxications
- N-acetylcysteine
- Flumazenil
- O2
- Na Thiosulfate
- Fomepizole
- Succimer
- Dimercaprol
- Naloxane
- Atropine
- Pralidoxime
- Penicillamine
- Deferoxamine
- Charcoal
Define Toxicology
Study of the adverse effects of xenobiotics (foreign bodies) on living systems
What differentiates a poison from a remedy?
Right dose
How many patients in the USA present with acute poisoning?
8 million patients; Accounting for 10-20% of hospital admissions
True or False. Chronic toxicity from low-dose toxicants may take years to develop a clinical presentation
True
What causes the highest poison exposure for all group w/ fatal outcomes?
Medications
What other substances can cause poison exposure in all age groups?
Low yield
- Cosmetic, personal care items
- Cleaning substances (fatal outcome)
- Pesticides (fatal outcome)
- Art & crafts, office supples
- Alcohols (fatal outcome)
- Food products
- Plants
- Gas, fumes, chemicals (fatal outcome)
- Automotive products (fatal outcome)
What types of medications are most frequently involved in human poisoning exposures?
Analgesics (Aspirin, Ibuprofen, Acetaminophen)
What are the three ways to get exposed to a toxicant?
- Skin contact
- Ingestion
- Inhalation
What occurs in the body when exposed to a toxicant?
Distributed throughout the body, activated or inactivated, interacts with cells which can result in toxicity
What organ is affected by inhaled gases/particles?
Lungs
What organ(s) are affected by ingested chemicals? (4)
- Liver (Bioactivation or inactivation)
- Brain (Lipophilic)
- Kidney
- Heart (disruption of ion gradients)
Which compounds have selective toxicity?
- Enzymes
- Receptors (helps choose antibodies)
Which compounds have non-selective toxicity?
- Acids
- Bases
What outcome occurs with immediate toxicity?
Skin damage
What outcome occurs with delayed toxicity?
Cancer (Chronic exposure)
What method of toxicant exposure occurs with Halogenated hydrocarbons (CCl4 & CHCl3)?
Carbon tetrachloride (CCl4)
Chloroform (CHCl4)
Inhalation/Ingestion
True or False. Halogenated hydrocarbons (CCl4 & CHCl3) can penetrate the blood-brain barrier (BBB).
Carbon tetrachloride (CCl4)
Chloroform (CHCl4)
True.
b/c lipid soluble
How do most Halogenated hydrocarbons (CCl4 & CHCl3) affect the CNS?
Carbon tetrachloride (CCl4)
Chloroform (CHCl4)
- Depress the CNS w/ acute high exposure
What is the treatment for Halogenated hydrocarbons (CCl4 & CHCl3)?
Carbon tetrachloride (CCl4)
Chloroform (CHCl4)
- Support treatment for acute intoxication
- Support tx (ABCD): Airway, Blood Pressure, Circulation, Decontamination
What is Support Treatment for toxicity?
Support tx: ABCD
Maintainance of the Airway, Blood Pressure, Circulation and Decontamination of the patient
How can you get exposed to Carbon Tetrachloride (CCl4)?
Halogenated hydrocarbons
Contaminated drinking H2O
What side effects does CCl4 have at low concentrations? high concentrations?
Low concentrations
- Irritating to eyes & respiratory system
High concentrations
- Nausea, Vomiting, Stupor, Seizures,Coma, Death (CNS depression)
How is CCl4 bioactivated?
By cytochrome P450 (CYP) which produces free radicals that can cause damage to macromolecules, e.g., lipid peroxidation
What are the side effects of acute nonlethal exposure to CCl4?
- Produce liver and kidney damage
- Can occur in several hours to days
What side effects occur when exposed to Chloroform (CHCl3)?
- Similar to CCl4
- Dizziness, Headaches, Facilitated catecholamine-induced arrhythmias
Describe the normal pathway for CHCl3 detoxification. And what occurs to cause toxicity?
Normal Pathway
- CHCl3 (cholorform) →CYP2E1 (biotransformation)→Phosgene (Reactive metabolite)→GSH-Glutathione Transferase (protects organ damage)→Detoxified product
Toxicity
- GSH gets saturated and can NO longer inactive Phosgene →Hepatotoxicity
How can you get exposed to Aromatic Hydrocarbons?
Benzene, Toluene
Inhalation/Ingestion
What side effects occur with high acute exposure to Aromatic Hydrocarbons?
Benzene, Toluene
- CNS depression
- Catecholamine-induced arrhythmias
What is the treatment for Aromatic hydrocarbons?
Benzene, Toluene
Support treatment (ABCD) for acute intoxication
What ways can you be exposed to Benzene
Aromatic hydrocarbons
- 1/2 national exposure via tobacco smoke
- Combustion of fossil fuels/contaminated H2O
What diseases can chronic exposure to Benzene cause?
Aromatic hydrocarbons
Hematopoietic toxicity:
- Agranulocytosis
- Leukemia (AML)
Note: AML=
- M3 subtype: Promyelocytic leukemia
- M5 subtype: Monocytic leukemia
In what ways can you be exposed to Toluene?
Aromatic hydrocarbons
- Gasoline (1°)
- Degreasers
- Paint
- Furniture polish
- Abuse: Bagging/huffing feeling Euphoric
What side effects does exposure to Toluene cause?
Aromatic Hydrocarbons
- CNS depression→drowsiness, ataxia, tremors, impaired speech, hearing loss
- Chronic exposure-Liver and kidney damage
- High concentrations- Death