Toxicology UTA Exam 1 with Complete
Solutions
Toxicology - ANSWER-The study and/or practice of toxicology uses several different
disciplines and applications.
It is not "all-or-none", depends on a variety of factors
Toxicology Is Interdisciplinary - ANSWER-It is interdisciplinary (draws on other sciences
to advance)
It basically asks the question "what will this chemical do to this system?"
Reference to poisons has been around as long as the written word; it isn't new and has
been proven many times
Toxicology Is Multifaceted - ANSWER-It affects many areas of daily life/ is pertinent in
terms of:
~Nature: for example snake bites and ecosystems
~Synthetics: ex. medicines and chemicals
~Crime: ex. politicians have been poisoned since the BC era, such as Viktor
Yushchenko was poisoned with Dioxin in November 2004
~Jobs: ex. occupational hazards and is where you're most exposed to toxic substances
~Regulatory agencies- government regulated
~Economic impact: such as asthma attack triggers cause many to go to the ER which
costs money
~Ethics: for example a new chemotherapy is developed so you need to provide
information about its risks
~Specific Populations: or susceptible or unique populations for example, give children
liquid meds or prescribe medications based on their body weight due to unmatured
organs, so we don't want to give them too much [i.e overdosage]
Paracelsus - ANSWER-He said, "All substances are poisons; there is none that is not a
poison. The right dose differentiates a poison from a remedy."
He is known as the Father of Toxicology
*****Meaning THE DOSE MAKES THE POISON!!!
The Dose Makes The Poison - ANSWER-Not enough dose = no remedy
Correct dosage = remedy
Too Much = makes the poison
,For example, chemotherapy just enough and it helps with cancer but too much radiation
and it could kill the patient
Principles According to Paracelsus - ANSWER--Chemical is the primary toxic agent
-Experimentation is essential in observing responses to chemicals
-Therapeutic vs. toxic properties of chemicals: some can be both therapeutic and toxic
such as cancer treatments~ chemotherapy and radiation
-Sometimes only dose distinguishes between harmful and helpful (The Dose Makes The
Poison)
-Specific chemicals and their effects can be determined
~Discrete chemical compound is primary toxic agent ex. cigarette smoke (mixture
carcinogen~ about 40 of these carcinogens cause cancer)
~Experimentation is key!!!
~Toxicology can be studied because of this
Brief History w/ Chemical Carcinogenesis as an Example - ANSWER-1700- Ramazzini
observed increased incidence of breast cancer among nuns may be due to they won't
experience pregnancy as a protective factor [an EPIDEMIOLOGICAL observation; at
this time no experiments]
1775- Percival Pott reported increased incidence of scrotal cancer in chimney sweeps
[epidemiological observation]
1918- Yamagiwa and Ichikawa introduced multiple topical applications of coal tar to
rabbit ears produced skin carcinomas.
~First demonstration that a chemical could produce cancer in animals
~Confirmed Pott's observations, providing a link between animal studies and
epidemiology studies.
~Why are animals not perfect predictors? Because they are genetically different, have
different metabolic reactions, etc.
1930s- Kennaway isolated benzo[a]pyrene from coal tar showing it as the discrete
chemical compound or toxic agent
1940s- James & Elizabeth Miller showed relationship between metabolic activation,
DNA adduct formation, and tumorigenesis; showed benzo[a]pyrene's structure gets
changed (metabolic activation), then bound to DNA (adduct formation) causing cancer
Poison - ANSWER-Any agent capable of producing a deleterious response in a
biological system
Mechanistic Toxicologist - ANSWER-Identifies the cellular, biochemical, and molecular
mechanisms by which chemicals exert toxic effects on living organisms
,Toxicogenomics - ANSWER-Permits mechanistic toxicologists to identify and protect
genetically susceptible individuals from harmful environmental exposures, and to
customize drug therapies based on their individual genetic makeup
Descriptive Toxicologist - ANSWER-Is concerned directly with toxicity testing, which
provides information for safety evaluation and regulatory requirments
Regulatory Toxicologist - ANSWER-Determines from available data whether a chemical
poses a sufficiently low risk to be marketed for a stated purpose and establishes
standards for the amount of chemicals permitted in ambient air, industrial atmospheres,
and drinking water
Forensic Toxicologist - ANSWER-Is a hybrid of analytic chemistry and fundamental
toxicologic principles that focuses primarily on the medicolegal aspects of the harmful
effects of chemicals on humans and animals
Clinical Toxicology - ANSWER-Is concerned with disease caused by or uniquely
associated with toxic substances
Environment Toxicology - ANSWER-Focuses on the impacts of chemical pollutants in
the environment on biological organisms, specifically studying the impacts of chemicals
on non-human organisms such as fish, birds, terrestrial animals, and plants.
Ecotoxicology - ANSWER-A specialized area within environmental toxicology, focusing
specifically on the impacts of toxic substances on population dynamics in an ecosystem
Developmental Toxicology - ANSWER-The study of adverse effects on the developing
organism that may result from exposure to chemical or physical agents before
conception (either parent), during prenatal development, or postnatally until the time of
puberty
Teratology - ANSWER-The study of defects induced during development between
conception and birth
Reproductive Toxicology - ANSWER-The study of the occurrence of adverse effects on
the male or female reproductive system that may result from exposure to chemical or
physical agents
LD50 - ANSWER-Lethal dose for 50% of the population
-The dose makes the poison; it shows how all discrete chemicals interact with the
environment and behave in different ways
-It has a very broad range
-LD50 does not accurately reflect the full spectrum of toxicity; it only takes into account
death not side effects, cancer, etc
Toxin - ANSWER-Meaning from nature
, Toxicant - ANSWER-Meaning from humans; but be careful since most use toxin to
describe "everything"
People Respond Differently to Toxins - ANSWER--Genetics: age
-Lifestyle: health level, weight, smoking, drinking, obesity, environmental exposures, etc
-Epigenetics: chemicals bind to your genome or detach which affects gene expression;
some proteins may not be made, coded for, turn on or off, etc. Environmental exposures
affect epigenome which affects genes turning on or off which determine proteins made,
etc
Carcinogenic Factors Associated with Lifestyle - ANSWER-1) Tobacco smoking:
Associated Neoplasm- mouth, pharynx, larynx, lung, esophagus, & bladder
Evidence for Carcinogenicity- sufficient
2) Dietary exposure- increased caloric intake
3) Alcoholic beverages
Associated Neoplasm- esophagus, liver, oropharynx, and larynx
Evidence for Carcinogenicity- sufficient
4) Aflatoxins
Associated Neoplasm- liver
Evidence for Carcinogenicity- sufficient
5) Excess fat, protein, calories
Associated Neoplasm- breast, colon, endometrium, and gall bladder
Evidence for Carcinogenicity- sufficient
6) Reproductive History
7) Late age at first pregnancy
Associated Neoplasm- breast
Evidence for Carcinogenicity- sufficient
8) Zero or low parity
Associated Neoplasm- ovary
Evidence for Carcinogenicity- sufficient
Undesired Effects - ANSWER-Chemical Idiosyncrasy
Allergic reactions
Immediate vs delayed (acute vs. chronic)
Reversible vs irreversible
Local vs Systemic and ADME
Solutions
Toxicology - ANSWER-The study and/or practice of toxicology uses several different
disciplines and applications.
It is not "all-or-none", depends on a variety of factors
Toxicology Is Interdisciplinary - ANSWER-It is interdisciplinary (draws on other sciences
to advance)
It basically asks the question "what will this chemical do to this system?"
Reference to poisons has been around as long as the written word; it isn't new and has
been proven many times
Toxicology Is Multifaceted - ANSWER-It affects many areas of daily life/ is pertinent in
terms of:
~Nature: for example snake bites and ecosystems
~Synthetics: ex. medicines and chemicals
~Crime: ex. politicians have been poisoned since the BC era, such as Viktor
Yushchenko was poisoned with Dioxin in November 2004
~Jobs: ex. occupational hazards and is where you're most exposed to toxic substances
~Regulatory agencies- government regulated
~Economic impact: such as asthma attack triggers cause many to go to the ER which
costs money
~Ethics: for example a new chemotherapy is developed so you need to provide
information about its risks
~Specific Populations: or susceptible or unique populations for example, give children
liquid meds or prescribe medications based on their body weight due to unmatured
organs, so we don't want to give them too much [i.e overdosage]
Paracelsus - ANSWER-He said, "All substances are poisons; there is none that is not a
poison. The right dose differentiates a poison from a remedy."
He is known as the Father of Toxicology
*****Meaning THE DOSE MAKES THE POISON!!!
The Dose Makes The Poison - ANSWER-Not enough dose = no remedy
Correct dosage = remedy
Too Much = makes the poison
,For example, chemotherapy just enough and it helps with cancer but too much radiation
and it could kill the patient
Principles According to Paracelsus - ANSWER--Chemical is the primary toxic agent
-Experimentation is essential in observing responses to chemicals
-Therapeutic vs. toxic properties of chemicals: some can be both therapeutic and toxic
such as cancer treatments~ chemotherapy and radiation
-Sometimes only dose distinguishes between harmful and helpful (The Dose Makes The
Poison)
-Specific chemicals and their effects can be determined
~Discrete chemical compound is primary toxic agent ex. cigarette smoke (mixture
carcinogen~ about 40 of these carcinogens cause cancer)
~Experimentation is key!!!
~Toxicology can be studied because of this
Brief History w/ Chemical Carcinogenesis as an Example - ANSWER-1700- Ramazzini
observed increased incidence of breast cancer among nuns may be due to they won't
experience pregnancy as a protective factor [an EPIDEMIOLOGICAL observation; at
this time no experiments]
1775- Percival Pott reported increased incidence of scrotal cancer in chimney sweeps
[epidemiological observation]
1918- Yamagiwa and Ichikawa introduced multiple topical applications of coal tar to
rabbit ears produced skin carcinomas.
~First demonstration that a chemical could produce cancer in animals
~Confirmed Pott's observations, providing a link between animal studies and
epidemiology studies.
~Why are animals not perfect predictors? Because they are genetically different, have
different metabolic reactions, etc.
1930s- Kennaway isolated benzo[a]pyrene from coal tar showing it as the discrete
chemical compound or toxic agent
1940s- James & Elizabeth Miller showed relationship between metabolic activation,
DNA adduct formation, and tumorigenesis; showed benzo[a]pyrene's structure gets
changed (metabolic activation), then bound to DNA (adduct formation) causing cancer
Poison - ANSWER-Any agent capable of producing a deleterious response in a
biological system
Mechanistic Toxicologist - ANSWER-Identifies the cellular, biochemical, and molecular
mechanisms by which chemicals exert toxic effects on living organisms
,Toxicogenomics - ANSWER-Permits mechanistic toxicologists to identify and protect
genetically susceptible individuals from harmful environmental exposures, and to
customize drug therapies based on their individual genetic makeup
Descriptive Toxicologist - ANSWER-Is concerned directly with toxicity testing, which
provides information for safety evaluation and regulatory requirments
Regulatory Toxicologist - ANSWER-Determines from available data whether a chemical
poses a sufficiently low risk to be marketed for a stated purpose and establishes
standards for the amount of chemicals permitted in ambient air, industrial atmospheres,
and drinking water
Forensic Toxicologist - ANSWER-Is a hybrid of analytic chemistry and fundamental
toxicologic principles that focuses primarily on the medicolegal aspects of the harmful
effects of chemicals on humans and animals
Clinical Toxicology - ANSWER-Is concerned with disease caused by or uniquely
associated with toxic substances
Environment Toxicology - ANSWER-Focuses on the impacts of chemical pollutants in
the environment on biological organisms, specifically studying the impacts of chemicals
on non-human organisms such as fish, birds, terrestrial animals, and plants.
Ecotoxicology - ANSWER-A specialized area within environmental toxicology, focusing
specifically on the impacts of toxic substances on population dynamics in an ecosystem
Developmental Toxicology - ANSWER-The study of adverse effects on the developing
organism that may result from exposure to chemical or physical agents before
conception (either parent), during prenatal development, or postnatally until the time of
puberty
Teratology - ANSWER-The study of defects induced during development between
conception and birth
Reproductive Toxicology - ANSWER-The study of the occurrence of adverse effects on
the male or female reproductive system that may result from exposure to chemical or
physical agents
LD50 - ANSWER-Lethal dose for 50% of the population
-The dose makes the poison; it shows how all discrete chemicals interact with the
environment and behave in different ways
-It has a very broad range
-LD50 does not accurately reflect the full spectrum of toxicity; it only takes into account
death not side effects, cancer, etc
Toxin - ANSWER-Meaning from nature
, Toxicant - ANSWER-Meaning from humans; but be careful since most use toxin to
describe "everything"
People Respond Differently to Toxins - ANSWER--Genetics: age
-Lifestyle: health level, weight, smoking, drinking, obesity, environmental exposures, etc
-Epigenetics: chemicals bind to your genome or detach which affects gene expression;
some proteins may not be made, coded for, turn on or off, etc. Environmental exposures
affect epigenome which affects genes turning on or off which determine proteins made,
etc
Carcinogenic Factors Associated with Lifestyle - ANSWER-1) Tobacco smoking:
Associated Neoplasm- mouth, pharynx, larynx, lung, esophagus, & bladder
Evidence for Carcinogenicity- sufficient
2) Dietary exposure- increased caloric intake
3) Alcoholic beverages
Associated Neoplasm- esophagus, liver, oropharynx, and larynx
Evidence for Carcinogenicity- sufficient
4) Aflatoxins
Associated Neoplasm- liver
Evidence for Carcinogenicity- sufficient
5) Excess fat, protein, calories
Associated Neoplasm- breast, colon, endometrium, and gall bladder
Evidence for Carcinogenicity- sufficient
6) Reproductive History
7) Late age at first pregnancy
Associated Neoplasm- breast
Evidence for Carcinogenicity- sufficient
8) Zero or low parity
Associated Neoplasm- ovary
Evidence for Carcinogenicity- sufficient
Undesired Effects - ANSWER-Chemical Idiosyncrasy
Allergic reactions
Immediate vs delayed (acute vs. chronic)
Reversible vs irreversible
Local vs Systemic and ADME
