TOX 401 Exam with 100% Correct
Solutions
Descriptive Toxicology - ANS-concerned directly with toxicity testing which provides
information for safety evaluation and regulatory requirements. How toxic is it?
Mechanistic toxicology - ANS-concerned with identifying and understanding the
mechanisms by which chemicals exert toxic effects on living organisms. How is it toxic?
Regulatory toxicology - ANS-Concerned with responsibility for deciding on the basis of
data provided by descriptive and mechanistic toxicologists. Whether a drug or chemical
poses a sufficient low risk to be marketed for a stated purpose.
Forensic toxicology - ANS-hybrid between analytical chemistry and toxicology. Main
concern is establishing cause of death and determining its circumstances in a
postmortem investigation.
Clinical Toxicology - ANS-Concerns realm of medical science. Deals with disease
caused by or associated with toxic substance.
Environmental toxicology - ANS-Concerned with impacts of toxic substances on
populations and ecosystems
Three Functions to be described after a toxicant is Introduced into the environment or
organism - ANS-Fate and transformation of toxicants
Interaction with site of action
Effects
Toxicant - ANS-Anything that's toxic to you (synthetic)
Can be produced by anything
Toxin - ANS-A natural product with toxic effects. Ex: venom
Exposure Phase - ANS-The duration an organism is exposed
Toxicokinetic Phase - ANS-The uptake and distribution, metabolism, and elimination of
the toxin
Toxicodynamic Phase - ANS-The biological tissue cellular and molecular phase and
interaction with receptors
Direct interaction of toxin and tissue
, LD50 - ANS-the amount of a chemical that kills 50% of the animals in a test population
LC50 - ANS-Concentration of a substance needed to kill 50% of the organisms
ED50 - ANS-Dose or amount of chemical per unit weight that elicits an adverse effect in
50% of the population
EC50 - ANS-Concentration that elicits an adverse effect in 50% of the test population
Acute Toxicity - ANS-Immediate effects associated with single or short-term exposure
(24-96 hours)
Chronic Toxicity - ANS-A delayed effect usually following low levels of repeated
exposure- perhaps over several months or years
Ex: Tobacco Smoke
Subchronic Toxicity - ANS-Continuous exposure over weeks or months
Standard Measures
-NOEC (threshold)
-NOAEC
-LOEC
-MTC
-MATC - ANS--No Observable Effect Concentration
-No Observable Adverse Effect Concentration
-Lowest Observable Effect Concentration
-Minimum Threshold Concentration
-Maximum Allowable Toxicant Concentration
DES daughters - ANS-75% of females (19-22) exposed to DES in utero (18 wks)
developed vaginal clear cell adenocarcinoma
Reproductive tract structural differences (T-shaped uterus)
Pregnancy compilations- ectopic pregnancy and pre-term delivery
Infertility
Now- 2.5 increase in breast cancer
DES sons - ANS-Non-cancerous epididymal cysts on the testicles
Other genital abnormalities
Cryptorchidism, hypospadias, microphallus
15-32% of DES Sons compared with 5-%
Infertility??
DES grandchildren - ANS-Increased reproductive cancer in female "grandchildren" of
mice who were injected with DES
Potential great-grandchild effec
Solutions
Descriptive Toxicology - ANS-concerned directly with toxicity testing which provides
information for safety evaluation and regulatory requirements. How toxic is it?
Mechanistic toxicology - ANS-concerned with identifying and understanding the
mechanisms by which chemicals exert toxic effects on living organisms. How is it toxic?
Regulatory toxicology - ANS-Concerned with responsibility for deciding on the basis of
data provided by descriptive and mechanistic toxicologists. Whether a drug or chemical
poses a sufficient low risk to be marketed for a stated purpose.
Forensic toxicology - ANS-hybrid between analytical chemistry and toxicology. Main
concern is establishing cause of death and determining its circumstances in a
postmortem investigation.
Clinical Toxicology - ANS-Concerns realm of medical science. Deals with disease
caused by or associated with toxic substance.
Environmental toxicology - ANS-Concerned with impacts of toxic substances on
populations and ecosystems
Three Functions to be described after a toxicant is Introduced into the environment or
organism - ANS-Fate and transformation of toxicants
Interaction with site of action
Effects
Toxicant - ANS-Anything that's toxic to you (synthetic)
Can be produced by anything
Toxin - ANS-A natural product with toxic effects. Ex: venom
Exposure Phase - ANS-The duration an organism is exposed
Toxicokinetic Phase - ANS-The uptake and distribution, metabolism, and elimination of
the toxin
Toxicodynamic Phase - ANS-The biological tissue cellular and molecular phase and
interaction with receptors
Direct interaction of toxin and tissue
, LD50 - ANS-the amount of a chemical that kills 50% of the animals in a test population
LC50 - ANS-Concentration of a substance needed to kill 50% of the organisms
ED50 - ANS-Dose or amount of chemical per unit weight that elicits an adverse effect in
50% of the population
EC50 - ANS-Concentration that elicits an adverse effect in 50% of the test population
Acute Toxicity - ANS-Immediate effects associated with single or short-term exposure
(24-96 hours)
Chronic Toxicity - ANS-A delayed effect usually following low levels of repeated
exposure- perhaps over several months or years
Ex: Tobacco Smoke
Subchronic Toxicity - ANS-Continuous exposure over weeks or months
Standard Measures
-NOEC (threshold)
-NOAEC
-LOEC
-MTC
-MATC - ANS--No Observable Effect Concentration
-No Observable Adverse Effect Concentration
-Lowest Observable Effect Concentration
-Minimum Threshold Concentration
-Maximum Allowable Toxicant Concentration
DES daughters - ANS-75% of females (19-22) exposed to DES in utero (18 wks)
developed vaginal clear cell adenocarcinoma
Reproductive tract structural differences (T-shaped uterus)
Pregnancy compilations- ectopic pregnancy and pre-term delivery
Infertility
Now- 2.5 increase in breast cancer
DES sons - ANS-Non-cancerous epididymal cysts on the testicles
Other genital abnormalities
Cryptorchidism, hypospadias, microphallus
15-32% of DES Sons compared with 5-%
Infertility??
DES grandchildren - ANS-Increased reproductive cancer in female "grandchildren" of
mice who were injected with DES
Potential great-grandchild effec
