What is the study of poisonous substances?
What are the routes of exposure to toxins?
What is the term for the amount of damage done to an organism when the substance is administered at less than the lethal dose?
What is a one-time exposure of short duration to an agent that immediately causes a toxic response?
What is the term for multiple exposures for extended time periods to an agent at a dosage that will not cause an acute response?
What type of test is performed first and usually of a qualitative nature and may lack specificity?
What type of test is usually quantitative with good specificity and sensitivity?
What are alcohols considered?
Volatile organic substances
Name the different types of alchols
- Ethylene glycol
What clinical condition is associated with ethanol?
What clinical condition is associated with methanol?
- Severe acidosis
- Death due to methanol conversion to formaldehyde
What clinical condition is associated with isopropanol?
- Severe and acute symptoms of toxic haptitis and cirrhosis
- Symptoms persist for a long time because isopropanol is matabolized to acetone - which has a long half life
What clinical condition is associated with ethylene glycol?
- Severe metabolic acidosis
- Renal tubular damage
Where is ethylene glycol found?
Why is carbon monoxide considered toxic?
- It binds tightly to hemoglobin and does not allow oxygen to attach to the hemoglobin
- Forms carboxyhemoglobin
What clinical condition is associated with carbon monoxide?
Hypoxia in the brain and heart
How does cyanide exposure occur?
- Oral ingestion
- Transdermal absorption
Where is cyanide used, typically?
Why is cyanide considered supertoxic?
Binds to heme iron and mitochondrial cytochrome oxidase
How does aresenic travel in the blood?
Binds to thiol groups in proteins
How is arsenic excreted?
Ionized arsenic is excreted in the urine
What specimens are used to assess the level of arsenic poisoning?
- Short term exposure: Blood and urine
- Long term exposure: Hair and fingernails
Why is lead considered toxic?
- Binds to proteins
- Inhibits many enzymes
- Inhibits heme synthesis
What lab results are consistent with lead poisoning?
- Basophili stippling of RBCs
- Increased urinary excretion of aminolevulinic acid and coproporphyrins
What is the acceptable blood lead level in young children?
Why is mercury considered toxic?
- Binds to proteins
- Inhibits many enzymes
What do organophophate and carbamate insecticides inhibit?
What is the function of salicylate (aspirin)?
What happens at toxic doses of salicylate (aspirin)?
- Mixed acid-base imbalance seen in metabolic acidosis and respiratory alkalosis (respiratory center stimulant)
- Ketone body formation
- Excess formation of lactate
What is the function of acetaminophen (tylenol)?
What is the toxic effect of acetaminophen (tylenol)?
What is the function of amphetamine and methamphetamine?
- Treat narcolepsy and disorders that affect ability to focus
- Provide a sense of mental and physical well-being
What is the function of anabolic steroids?
- Increase muscle mass
- Increase athletic perfomance
What is the function of cannabinoids?
- Provide a feeling of mental well being and euphoria
- Impair mental function
- Impair short term memory
What is the primary cannabinoid component of marijuana?
What is the half life of THC?
- One day following single use
- 3-5 days following chronic use
How long is THC detectable in urine?
- 3-5 days following single use
- Up to 4 weeks following chronic use
What is the function of cocaine?
- Local anesthetic
- CNS stimulant
What is the primary metabolite of cocaine?
When is benzoylecgonine detectable in the urine?
- 3 days following single use
- 20 days following chronic use
What are the different types of opiates found?
- Naturally occurring: opium, morphine, codeine
- Chemically modified: heroin, dilaudid, oxycodone
- Synthetic: Demerol, methadone, darvon, talwin, fentanyl
What is the function of opiates?
- Anesthetic properties
What is associated with opiate use?
What is the function of phencyclidine (PCP)?
- Hallucinogenic effects
When is phencyclidine (PCP) detectable in the urine?
Up to 7-30 days following chronic use
Name the different types of tranquilizers
- Barbiturates: Phenobarbital, amobarbital, secobarbital, and pentobarbital
- Benzodiazepines: Diazepam (valium), chlordiazepoxide, lorazepam
What is the function of tranquilizers?
Sedative hypnotics that produce depression of the CNS
What is clinical condition is associated with tranquilizers?