PK Gupta Series 7: Multiple Choice Questions and fill in blanks TOXICOLOGY Question and Answer bank.

Series 7: Multiple Choice Questions and fill in blanks

Multiple Choice Questions

Exercises

Q. 1. Examples of significant concentrations of a toxicant in a tissue that is not a target organ include all of the following except-----------.

a) lead in bone

b) DDT in adipose tissue

c) paraquat in lung

d) TCDD in adipose tissue

Q. 2. the ability of a chemical to cause acute skin and eye irritation is usually evaluated in a ------

a) rabbit

b) rat

c) mouse

d) dog

Q. 3.  before a potential pharmaceutical compound can be given to humans .-------.

a) an NDA must be filed with the FDA

b) an IND must be filled with the FDA

c) acute toxicity studies on 4 species must be conducted

d) a 2-year dog carcinogenicity study must be completed

Q. 4.  phase 1 clinical trials are conducted to determine all of the following except ---

a) pharmacokinetics

b) safety

c) rare adverse effects

d) preliminary efficacy

Q. 5. MTD stands for ------------------

a) minimum tolerated dose

b)maximum total dose

c) maximum tolerated dose

d) maximum threshold dose

Q. 6. the acute toxicity study in animals provides ------

a) an appropriate lethal dose

b) information on target organs

c) information on dose selection for long-term studies

d)all of the above

Q. 7. a subacute toxicity study in rats usually lasts ------.

a) 3 days

b)14 days

c) 3 months

d) 6 months

Q. 8. the period of organogenesis in rats is ---.

a) day 3-10

b) day 7-17

c)  day 12-25

d) day 17-56

Q. 9.  a dose of investigational drug that suppresses body weight gain slightly in a 90-day animal study is defined by some regulatory agencies to be-------.

a) LOAEL

b) NOAEL

c)MTD

d) reference dose

Q. 10. a subchronic animal study required by the FDA will usually include-----

a) two species (usually one rodent and one nonrodents)

b) both genders

c) at least three doses (low, intermediate, and high)

d) all of the above

Q.11 A dose of a compound A is toxic to animals in vivo. Another chemical B is not toxic when given at doses several orders of magnitude higher but when the two are given together the toxic response is greater than that of the given dose of A alone.

a) antagonism

b) synergism

c) additivity

d) potentiation

e) none of the above

Q.12 Which information may be gained from an acute toxicity study

a) no effect level

b) LD₅₀ 

c) therapeutic index

d) target organ

e) all of the above

Q.13The therapeutic index is usually defined as

a) TD₅₀ / LD₅₀ 

b) ED₅₀ / LD₅₀ 

c) LD₅₀   / ED₅₀

d) ED₅₀  / TD₅₀

e) LD₅₀   / ED₅₀

Q.14 1000 ppm is equivalent to 1%

a) True

b) False

Answers

1. c;      2. a;      3. b ;     4.c ;      5.c ;      6.d ;      7.b ;     8.b ;      9.c ;      10. d; 11. d; 12. e; 13. c ; 14. b.

Fill in blanks

Q. 1. The branch of science which deals with the harmful effects of physical and chemical agents of human and animal life is ------------------------------------

Q. 2. In the term toxicology, the word ‘toxicon’ (Greek) means --------------------

Q. 3. The branch of toxicology, which deals with diagnosis, treatment and management of toxic substances, is known as -----------------------------------

Q. 4. The development and interpretation of mandatory toxicology testing programs is addressed by -------------------------------------------

Q. 5 Investigating and controlling the toxic effects of various substances on the community is dealt by ----------------------.

Q. 6. The study of toxicity produced by subsances of plant, animal and microbial origin is termed as -------------

Q. 7. A foreign chemical substance, which is not normally produced in the body or forms a part of the food, is known as --------------------.

Q. 8. The source of adverse effect/ damage is known as ----------------------

Q. 9. The likelyhood/probability of adverse effect upon exposure to a hazard is known as --------------------.

Q. 10. The statement, “all substances are poisons; the dose differentiates poison from a remedy” is associate with -------------------------.

Answers

1.TOXICOLOGY; 2. POISON; 3.CLINICA L TOXICOLOGY; 4. REGULATORY TOX COLOGY; 5 TOXICOVIGILANCE; 6. TOXINOLOGY; 7. XENOIOTIC; 8 HAZARD. (eg: Water containing Fluoride; Here fluoride is the hazard and fluorosis is the adverse effect. Hazard is independent of dose or exposure i.e., it is present whether someone drinks the water or not).

9. RISK. (eg: While drinking water containing fluoride, the chances of getting fluorosis is called risk. Risk can range from 0 to 100% depending on dose and exposure i.e., one should be exposed to a hazard to calculate the risk); 10. PARACELSUS

Exercises

Q. 1 The scientist referred to as ‘Father of Toxicology’ is ------------------------

Q. 2.  DDT (Dichlorodiphenytrichloro ethane) which is used to control malaria and typus was discovered by ----------------------------

Q. 3. The person who is known as ‘Father of Nerve Agents’ is ------------------------------

Q. 4. The author of the book ‘Silent Spring’ in which the detrimental effect of DDT and other pesticides on environment –particularly on birds was document is -------------------------. 

Q. 5. Bhopal gas tragedy, which is considered to be the world’s worst industrial disaster, was caused due to the leakage of------------------------------------ from Union Carbide fertilizer company.

Q. 6. Use of thalidomide in pregnant women for treating women for treating morning sickness led to -------------------------condition in the infants.

Q. 7. If the action of one substance opposes or neutralizes the effect of another substance, the relationship is referred to as -------------------------..

Q. 8. Rodents are preferred for oral toxicity testing as they lack ------------------ reflex.

Q. 9. Maximum acceptable/ permitted amount of a drug present in feed and foods is known as ----------------------------------------------------------------------.

Q. 10. The highest dose of a compound, which produces adverse effects but no mortality is called -----------------------------------------------------------------------.

Answers

1. M.J.B. Orfila; 2. Pau Muller; 3 GERHARD SCHRADER; 4. RACHEL CARSON;5. METHYL-ISOCYANATE (MIC); 6. PHOCOMELIA; ;7. ANTAGONISM (All antidotes have antagonistic relationship with their respective toxicants) have antagonistic relationship with the irrespective toxicants); 8. VOMITION; 9 MAXIMUM RESIDUE LEVEL (MRL). (For pesticides – MAXIMUM RESIDUE LIMIT); 10 MAXIMUM TOLERATED DOSE {(MTD),  MTD is also referred to as LD0 (Zero) as it will cause adverse effects but no mortality)}.

Exercise

Q.1. If the period of exposure of a toxicant is more than 3 months, the type of study is termed as ---------------------.

Q. 2. The type of toxicity which results due to progressive accumulation of a toxicant in the body is known as ------------------------------.

Q. 3. The amount of toxicant in food and water, which can be consumed daily over a life time without any significant health risk, is called as ------------------------------------------.

Q. 4 Unlawful or criminal killing of animals through administration of poisonsis known as -----------------------

Q. 5. Unintentional addition of toxicants and contaminants in feed  and water is known as ----------------------.

Q. 6. Man -made sources of toxicants are referred to as ------------------------ sources.

Q. 7. Genetically determined abnormal reactivity of an individual to a chemical is known as----------------------------..

Q. 8. Failure to elicit a response to an ordinary dose of a substance due prior usage is known as --------------------------.

Q. 9. The beneficial effects of toxic substances at low doses are known as-----------------.

Q. 10. In the event of irreparable injury, the cell undergoes a process of programmed cell death known as ----------------------------.

Q. 11 A substance is classified as extremely toxic if the lethal dose (LD) is LESS THAN ------------- and as practically non-toxic if the LD is ------------.

Q. 12. The ability of a substance to induce cancer is known as ------------------.    

Answers

1. CHRONIC TOXICITY; 2. CUMULATIVE TOXICITY(Several toxicants such as heavy metals, alcohol, DDT etc cause cumulative toxicity.); 3. ACCEPTABLE DAILY INTAKE (ADI); 4. MALICIOUS POISONING; 5. ACCIDENTAL POISONING; 6. ANTHROPOGENIC; 7. IDIOCYNCARY; 8. TOLERANCE(Tolerance is generally caused due to the induction of metabolizing enzymes in liver. However, in case of chronic alcoholism, pseudo-tolerance is observed, due to thickened GIT mucosa, which reduces absorption);

9. HORMESIS; 10. APOPTOSIS(Apoptosis is also involved in number of physiological process such as embryogenesis, ageing, cancer prevention etc); 11. 1mg/kg, 5 to 15 g/kg(It should be remembered that more the LD of a compound, less is its toxicity); 12. CARCINOGENESIS

FURTHER READING

Gupta PK (2018) Illustrative Toxicology with Question bank. 1st Edition. Elsevier, USA

Gupta PK (2016) Fundamentals of Toxicology: Essential concepts and applications. 1st Edition. ISBN-9780128054260, pp 438, BSP/Elsevier, USA

The Merck Veterinary Manual (2016). Chapter “Herbicide Poisoning” by PK GUPTA 11^th edition, Merck & Co. Inc Whitehouse Station, NJ, USA  2969-99

The Merck Veterinary Manual (2016). Chapter “Pentachlorophenol Poisoning” by PK GUPTA 11^th edition, Merck & Co. Inc Whitehouse Station, NJ, USA  pp 3052-53

Gupta PK (2016) Essential Concepts in Toxicology. Published by PharmaMed Press (A unit of BSP Books Pvt. Ltd), Hyderabad, India pp 362.

Gupta PK (2010) Modern Toxicology, Basis of organ and reproduction toxicity. Vol 1. Published by Pharma  Med Press (A unit of BSP Books Pvt. Ltd). Hyderabad, India pp 1-460.

Gupta PK (2010) Modern Toxicology, Adverse effects of xenobiotics. Vol 2, Published by PharmaMed Press (A unit of BSP Books Pvt. Ltd). Hyderabad, India pp 1-460.

Gupta PK (2010) Modern Toxicology, Immuno and clinicsal toxicology Vol 3. Published by PharmaMed Press (A unit of BSP Books Pvt. Ltd). Hyderabad, India pp 1-340.

                                                                                                                     To be cont'd

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PK Gupta Series 6: TOXICOLOGY Question and Answer bank( Multiple choice questions)

Series 6:  Multiple choice questions (choose the best statement)

Cont'd from series 5
Exercise 1

Q. 1.     A toxic substance produced by biological system is specially referred to as a  ------

a) toxicant

b) toxin

c) xenobiotic

d) poison

Q.2 Allergic contact dermatitis isa) a non-immune response caused by a direct action of an agent on the skin
b) an immediate type I hypersensitivity reaction
c) a delayed type IV hypersensitivity reaction
d) characterized by the intensity of reaction being proportional to the elicitation dose
e) not involved in photo-allergic reactions

Q.3. The reference dose (RfD) is generally determined by applying which of the following default procedures?
a) an uncertainty factor of 100 is applied to the NOAEL in chronic animal studies
b) a risk factor of 1000 is applied to the NOAEL in chronic animal studies
c) a risk factor of 10,000 is applied to the NOAEL in subchronic animal studies
d) an uncertainty factor between 10,000 and 1 million is applied to the NOEL from chronic animal studies
e) multiplying the NOAEL from chronic animal studies by 100

Q.4. Which of the following concerning the use of the "benchmark dose" in risk assessment is NOT correct?
a) can use the full range of doses and responses studied
b) allows use of data obtained from experiments where a clear "no observed adverse effect level" (NOAEL) has been attained
c) may be defined as the lower confidence limit on the 10% effective dose
d) is primarily used for analyses of carcinogenicity data and has limited utility for analyses of developmental and reproduction studies that generate quantal data
e) is not limited to the values of the administered doses

Q.5. Administration by oral gavage of a test compound that is highly metabolized by the liver versus subcutaneous injection will most likely result in
a) less parent compound present in the systemic circulation
b) more local irritation at the site of administration caused by the compound
c) lower levels of metabolites in the systemic circulation
d) more systemic toxicity
e) less systemic toxicity

Q.6. The phrase that best defines "toxicodynamics" is the
a) linkage between exposure and dose
b) linkage between dose and response
c) dynamic nature of toxic effects among various species
d) dose range between desired biological effects and adverse health effects
e) loss of dynamic hearing range due to a toxic exposure

Q.7. Which of the following was banned under the Delaney clause of the Food Additive Amendment of 1958?
a) butylated hydroxytoluene
b) sulfamethazine
c) cyclamate
d) phytoestrogens
e) aflatoxin

Q.8. Which of the following is NOT an initiating event in carcinogenesis?
a) DNA adduct formation
b) DNA strand breakage
c) mutation of proto-oncogenes
d) oxidative damage of DNA
e) mitogenesis

Q.9. Which of the following toxicity can occur due to single exposure?

a). Acute toxicity

b). Sub-acute toxicity

c). Sub-chronic toxicity

 d). Chronic toxicity

Q. 10. Which of the following assumptions is NOT correct regarding risk assessment for male reproductive effects in the absence of mechanistic data?

a) an agent that produces an adverse reproductive effect in experimental animals is assumed to pose a potential reproductive hazard to humans
b) in general, a non-threshold is assumed for the dose-response curve for male reproductive toxicity
c) effects of xenobiotics on male reproduction are assumed to be similar across species unless demonstrated otherwise
d) the most sensitive species should be used to estimate human risk
e) reproductive processes are similar across mammalian species

Answers

1, b; 2. c; 3.a; 4.d; 5a; 6.b; 7.c; 8.e; 9 a; 10. b.

Exercise 2

Q.1 Which of the following is characteristic of a non-genotoxic carcinogen?
a) has no influence on the promotional stage of carcinogenesis
b) would be expected to produce positive responses in in vitroassays for mutagenic potential
c) typically exerts other forms of toxicity and/or disrupts cellular homeostasis
d) generally shows little structural diversity
e) typically has little effect on cell turnover

Q.2.      A newly formed hapten protein complex usually stimulates the formation of a significant amount of antibodies in ---------------

a) 1 to 2 min

b) 1-2 hrs

c) 1-2 days

d) 1 to 2 weeks

Q.3. Prolonged muscle relaxation after succinylchioline is an example of a/an --

a)  IGE- mediated allergic reaction

b) idiosyncratic reaction

c) immune complex reaction

d) reaction related to a genetic increase in the activity of a liver enzyme

Q.4. Increased production of methemoglobin is due to decreased activity of -----

a) cytochrome P450 2B6

b) NADH cytochrome b5 reductase

c)cytochrome oxidase

d) cytochrome a3

Q.5. The most common target organ of toxicity is the ----

a) heart

b) lung

c)CNS (brain and spinal cord)

d) skin

Q.6. the organs least involved in systemic toxicity are ---

a) brain and peripheral nerves

b) muscle and bone

c)liver and kidney

d) hematopoietc system and lungs

Q.7.  If two organophosphate insecticides are absorbed into an organism, the result will be----

a) additive effect

b) synergestic effect

c) potentiation

d) substraction effect

Q.9. If propyl alcohol and carbon tetrachloride are chronically absorbed into an organism, the effect on the liver would be

a) additive effect

b) synergesic

c) potentiation

d) substraction effect

10. The treatment of strychnine induced convulsions by diazepam is an example of ----

a) chemical antagonism

b) dispositional antagonism

c) receptor antagonism

d)  functional antagonism

Answers

1. c:      2.d :     3.b :     4.b ;     5.c ;     6. b; 7.a ;          8.b ; 9.c ;          10. D.   .

Exercise 3

Q.1. The use of antitoxin in the treatment of snakebite is an example of ------

a) dispositional antagonism

b) chemical antagonism

c) receptor antagonism

d)  functional  antagonism

Q.2. The use of charcoal to prevent the absorption of diazepam is an example of ----

a) dispositional antagonism

b) chemical antagonism

c) receptor antagonism

d)  functional antagonism

Q.3. The use tamoxifen in certain breast cancer is an example of ---

a) dispositional antagonism

b) chemical antagonism

c) receptor antagonism

d)  functional antagonism

Q.4. Chemicals known to produce dispositional tolerances are ----

a) benzene and xylene

b) trichloroethylene and methylene chloride

c) paraquat and diaquat

d) carbon tetrachloride and cadmium

Q.5. The most rapid exposure to a chemical would occur through which of the following routes-------

a) oral

b) subcutaneous

c) inhalation

d) intramuscular

Q. 6. A chemical that is toxic to the brain but which is detoxified in the liver would be expected to be ---

a) more toxic orally than intramuscularly

b) more toxic rectally than intravenously

c)more toxic via inhalation than orally

d) more toxic on the skin than intravenously

 Q.7. The LD₅₀   is calculated from ------

a) a quantal dose-response curve

b) a hormesis dose –response curve

c) a graded dose-response curve

d) a log-log dose-response curve

Q.8. A U-shaped graded toxicity dose-response curve is seen in humans with----

a) pesticides

b) sedatives

c)  opiates

d) vitamins

Q. 9. The TD₁ / ED₉₉ is called-

a) margin of safety

b) therapeutic index

c) potency ratio

d) efficacy ratio

Q. 10.  All of the following are reasons for selective toxicity except--------

a) transport differences between cell

b)  biochemical differences between cell

c) cytology of male neurons versus female neurons

d) cytology of plant cells versus animal cells

Answers

1.       b;            2. a;       3. c;        4. d;       5. c;        6. c;     7. a;         8.d ;     9. a ;        10. c.    

Exercise 4

Q 1. Regulatory toxicology aims at guarding the public from dangerous chemical exposures, and depends primarily on which form of study:

a. observational human studies.

b. controlled laboratory animal studies.

c. controlled human studies.

d). environmental studies.

Q 2.  Risk from a public health perspective, is best described as the following:

a. undesirable endpoint is reached.

b. a possibility of a bad outcome.

c. likelihood of an unwanted outcome combined with uncertainty of when it will occur.

d. a bad outcome is assured and its mechanism is well understood.

Q 3. Which of the following statements is true regarding risk analysis?

a. it is a field of study that has been around for the last century.

b. it was developed by the pharmaceutical companies in response to concerns over new medications.

c. it is a relatively new field of study, spurred by new technologically-based risks.

d. it was largely a private sector venture.

Q 4. Which of the following are tools used in risk analysis?

a. toxicology

b. epidemiology

c. clinical trials

d. all of the above.

Q 5. Which of the following are common end points:

a. death

b. No Observable Effect Level

c. No Observable Adverse Effect Level

d. Lowest Observable Adverse Effect Level

e. All of the above.

Q. 6. The LD₅₀   is best described as which of the following:

a. the dose at which 50 % of all test animals die

b. the dose at which 50 % of the animals demonstrate a response to the chemical

c. the dose at which all of the test animals die

d. the dose at which at least one of the test animals dies

Q 7. The effective dose is best described as which of the following:

a. the dose at which 50 % of all test animals die

b. the dose at which some of the animals demonstrate a response to the chemical

c. the dose at which all of the animals demonstrate a response to the chemical

d. the dose at which 50 % of all test animals demonstrate a response to the chemical

Q 8. Extrapolation is best described as which of the following:

a. using known information to reach a conclusion.

b. using known information to infer something about the unknown.

c. using speculative information to infer something about the known.

d. a "best guess" approach.

Q. 9. Which of the following assumptions is NOT correct regarding risk assessment for male reproductive effects in the absence of mechanistic data?

a. an agent that produces an adverse reproductive effect in experimental animals is assumed to pose a potential reproductive hazard to humans.

b. in general, a non-threshold is assumed for the dose-response curve for male reproductive toxicity.

c. effects of xenobiotics on male reproduction are assumed to be similar across species unless demonstrated otherwise.

d. the most sensitive species should be used to estimate human risk

e. reproductive processes are similar across mammalian species

Q.10. Which of the following statements is true?

a) chemical carcinogens in animals are always carcinogens in animals

b) A chemical that is carcinogenic in humans is usually carcinogenic in at least one animal species

c) From a regulating perspective carcinogens are considered to have a threshold dose-response curve

d)  Arsenic is an example of a chemical that is carcinogenic to humans and nearly all species treated.

                                   

Answers:

1.       b; 2. c; 3. c; 4. d; 5. e; 6.a;7. d; 8. b; 9. b;10. c.

To be cont’d 

FURTHER READING

Gupta PK (2018) Illustrative Toxicology with Question bank. 1st Edition. Elsevier, USA

Gupta PK (2016) Fundamentals of Toxicology: Essential concepts and applications. 1st Edition. ISBN-9780128054260, pp 438, BSP/Elsevier, USA

The Merck Veterinary Manual (2016). Chapter “Herbicide Poisoning” by PK GUPTA 11^th edition, Merck & Co. Inc Whitehouse Station, NJ, USA  2969-99

The Merck Veterinary Manual (2016). Chapter “Pentachlorophenol Poisoning” by PK GUPTA 11^th edition, Merck & Co. Inc Whitehouse Station, NJ, USA  pp 3052-53

Gupta PK (2016) Essential Concepts in Toxicology. Published by PharmaMed Press (A unit of BSP Books Pvt. Ltd), Hyderabad, India pp 362.

Gupta PK (2010) Modern Toxicology, Basis of organ and reproduction toxicity. Vol 1. Published by Pharma  Med Press (A unit of BSP Books Pvt. Ltd). Hyderabad, India pp 1-460.

Gupta PK (2010) Modern Toxicology, Adverse effects of xenobiotics. Vol 2, Published by PharmaMed Press (A unit of BSP Books Pvt. Ltd). Hyderabad, India pp 1-460.

Gupta PK (2010) Modern Toxicology, Immuno and clinicsal toxicology Vol 3. Published by PharmaMed Press (A unit of BSP Books Pvt. Ltd). Hyderabad, India pp 1-340.

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Gupta's Series 1: TOXICOLOGY Question and Answer bank

General Toxicology: TOXICOLOGY Question and Answer bank

INTRODUCTION

TOXICOLOGY Question and Answer bank is aimed to make the study of toxicology simple and understandable through illustrations, images, custom made drawings, self-explanatory tables, and questions and answers collated from standard and authoritative textbooks, and widely scanned. The author’s own experience in different branches of toxicology including environmental and veterinary toxicology has been abstracted in these series of articles. This is first articles of series. The article has been written in a manner to stimulate interest on various facets of the subject and make it more exciting. It is general experience that theoretical description does not attract as much attention and interest as the illustrations and images. At the same time the information learnt through questions and their satisfactory replies make the topics easier to grasp them.

The book provides comprehensive quick reference for various examinations. However, it should be noted that this series serve only as a supplement and not as a replacement for any textbook and class room learning.

The series is expected to cover several topics such as general toxicology, principles of toxicology, risk assessment, disposition, mechanism of toxicity, toxic effects of various xenobiotics, poisonings of poisonous and venomous organisms, plant toxins, poisonous and food poisonings, radiation hazards and, abuse of drugs. The following series will also the adverse effects on environment and ecosystem exposed to various toxicants and poisonings as relevant to domestic and other animals.

Each article will be in the format of questions and answers, multiple choice questions, true and false statements or correct/ incorrect statements, fill in blanks, and matching the statements that will be useful for students, teachers and practicing in medical sciences, toxicology, pharmacology, medicine, pharmacy, environmental toxicology and in veterinary sciences.

WHO will be benefitted

The author believes that these series would be:

• A good alternative to be used for various courses and an excellent contribution for the students who needs a study aid for toxicology but wants more than a textbook as they need a self-testing regime.
• The teachers of toxicology who needs inspiration when composing questions for their students.
• The established toxicologists who wants to test their own knowledge of understanding the subject matter.
• Will be useful at universities and colleges, in industry for in-house training courses in toxicology which I know exist in some pharmaceutical and chemical companies
• Required for studying for the toxicology Boards and for preparation of different examinations.

Thus, the main strength of the series will reflect the breadth and multi-disciplinary nature of toxicology with illustrative approach to the subject that is needed to improve engagement with and understanding of the subject having a very wide audience.

Toxicology is a rapidly evolving field. Suggestions and comments are welcome to help the author improve the contents of the series. Please also suggest or send comments at drpkg_brly@yahoo.co.in ordrpkg1943@gmail.com

GENERAL TOXICOLOGY

Q. What is toxicology?

Toxicology is the study of the adverse effects of chemicals or physical agents on living organisms. The word  ‘toxicology’ is derived from the Greek word ‘toxicon’ which means ‘poison’ and logos means to study. It also includes study of special effects of toxicants developmental toxicity, teratogenicity, carcinogenicity, mutagenesis, immune-toxicity, neurotoxicity, endocrine disruption, etc.

Q. Who is the father of rational medicine?

Hippocrates (460-375 BC) is regarded as the “Father of Rational Medicine”. He created the Hippocratic oath. He believed that disease came naturally and not from superstitions and GOD. He advocated hot oil as an antidote in poisoning and induced vomiting to prevent absorption of the poisons.

Q. What do you know about Paracelsus?

Hohenheim-Paracelsus (1493–1541) a first century Roman physician, who promoted a focus on the toxicon, the toxic agent, as a chemical entity. He recognized the dose-response concept and in one of his writings stated, “All substances are poisons, there is none which is not a poison. The right dose differentiates a poison and a remedy”. 

Q. Who is Friedrich Serturner? What is his contribution?

Friedrich Serturner (1783-1841), German pharmacist who isolated the specific narcotic substance from opium and named as morphine after Morpheus, the Roman God of sleep.

Q. Who is a Father of Toxicology?

M J B (Mattie Josesph Benaventura) Orfila (1787-1853), a Spanish physician is a considered as “Father of Toxicology”.

Q. Describe main contributions of M J B Orfila (1787-1853).

He established toxicology as a discipline distinct from others and defined toxicology as the study of poisons. He advocated the practice of autopsy followed by chemical analysis of viscera to prove that poisoning has taken place. His “treatise” Traite des Poisons published in 1814 laid the foundations of forensic toxicology.

Q.   Who is father of experimental pharmacology? Describe in brief his contributions.

Francois Magendie (1783-1855) is known as the “Father of Experimental Pharmacology”, a pioneer French physiologist and toxicologist studied the mechanism of action of emetine, morphine, quinine, strychnine and other alkaloids.

Q. Who was Claude Bernard?

Claude Bernard (1813-1878) was a French physiologist who is considered the "Father" of Modern Experimental Physiology. Claude Bernard's first important works were carried out on the physiology of digestion, particularly the rôle of the pancreas exocrine gland, the gastric juices and of the intestines. In addition to this, Bernard also made other important contributions to the neurosciences.

Q. Who was Louis Lewin (1854-1929)?

Louis Lewin (1854-1929) was a German scientist who took up the task of classifying drugs and plants in accordance with their psychological effects. He also published many articles and books dealing with toxicology of methyl alcohol, ethyl alcohol, chloroform, opium, and some other chemicals. His important publications are “toxicologist’s view of world history” and “A textbook of toxicology”.

Q. Who discovered the insecticidal properties of DDT? What is his major contribution?

Paul Hermann Muller in 1939 discovered they of insecticidal properties of dichlorodiphenyltrichloroethane (DDT) .He was awarded Nobel Prize in 1948 “for his discovery of the high efficiency of DDT as a contact poison against several arthropods”.

Q. Who is “Father of Nerve Agents”?

Gerhard Schrader (1903-1990) was a German chemist who accidentally

developed the toxic nerve agents serin, tabun, soman, and cyclosarin while attempting to develop new insecticides. Schrader and his team, thus, introduced a new class of synthetic insecticides, the organophosphorus insecticides (OP), and defined the structural requirements for insecticidal activity of anticholinesterase (AChE) compounds. He is known as the “Father of Nerve Agents”. 

Q. Who is Rachel Carson (1907-1964)?

Rachel Carson 1962: started crusade against the use of DDT and published the great book “Silent Spring”.

 Q. What is Poison

Poison is any solid, liquid, gas that, when introduced into or applied to the body, can interfere with the life processes of cells of the organism. These effects occur by its own inherent chemical properties without acting mechanically and regardless of temperature.

Q. What is xenobiotic

xenobiotic is any substance, harmful or not, that is foreign to the body

Q. What is toxin

Any poison of biological origin is known as toxin

Q. What is another name for a poison?

Toxicant

Q. What category of toxins are encountered in our life?

bacterial (endotoxins, exotoxins),

fungal (mycotoxins),

plant (phytotoxins),

animal (zootoxins),

algal (phycotoxins)

Q. What toxicants are encountered in veterinary practice/ medicine?

pesticides,

drugs (animal and human),

household chemicals,

workplace chemicals,

feed additives,

poisonous gases

Q. What is toxic

The chemical that has the properties of a poison

Q. What is toxicity

amount of poison that, under a specific set of conditions, will cause a detrimental effect (agents are usually compared on a mg/kg basis, toxicity is not the condition produced by the toxicant)

Q. What is toxicosis

the condition (dz state) produced by the toxicant

what are other terms for toxicosis?

Q. What is venom

Venom is a toxicant synthesized in a specialized gland and ejected by the process of biting or stinging. Venom is also a zootoxin but is transmitted by the process of biting or stinging.

Q. What is pollutant

It is any undesirable substance solid, liquid or gaseous matter resulting from the discharge or admixture of noxious materials that contaminate the environment and contributes to pollution.

Q. What is systemic toxicant

It is a toxicant that affects the entire body or many organs rather than a specific site. For example, potassium cyanide is a systemic toxicant that affects virtually every cell and organ in the body by interfering with the cell’s ability to utilize oxygen.

Q. What is organ toxicant

It is toxicant that affects only specific organs or tissues (may be called tissue toxicant) while not producing damage to the body as a whole. For example, benzene is a specific organ toxicant in that it is primarily toxic to the blood-forming tissues.

Q. What is transient or reversible or temporary toxicity

It is the toxicity or harmful effect that remains for short duration of time. e.g., narcosis produced organic solvents.

Q. What is persistent or permanent or irreversible toxicity

It is the toxicity or harmful effects that persists throughout life span of the individual and are of permanent nature, e.g. scarring of skin produced by corrosives.

Q. What is immediate toxicity

It is the toxicity that develops shortly after a single exposure to a toxicant e.g. cyanide poisoning.

Q.  What is delayed toxicity

It is the toxicity or harmful effect which has delayed onset of action, e.g. peripheral neuropathy produced by some organophosphorus insecticides and radiation sickness.

Q. What is cumulative toxicity

It is progressive toxicity or harmful effect produced by summation of incremental injury resulting from successive exposures, e.g. liver fibrosis produced by ethanol.

 Accumulative effects:  occurs two ways...

a) accumulation of toxin: exposure to heavy metals (lead, mercury) that have long half-lives result in disease due to metal accumulation.

b) accumulation of effect: low level exposure to organophosphate pesticides depresses acetylcholine esterase to a point where symptoms occur.

Q. What is occupational (Industrial) toxicology

Occupational (Industrial) toxicology is concerned with health effects from exposure to chemicals in the workplace.  It deals with the clinical study of workers of industries and environment around him.

Q. What is regulatory toxicology:

It deals with administrative functions concerned with the development and interpretation of mandatory toxicology testing programs and controlling the use, distribution and availability of chemicals used commercially and therapeutically. For example, Food and Drug Administration (FDA) regulates drugs, cosmetics and food additives. Regulatory toxicology gathers and evaluates existing toxicological information to establish concentration-based standards of “safe” exposure. The standard is the level of a chemical that a person can be exposed to without any harmful health effects.

Q. What do you mean by regulation

Regulation is the control, by statute, of the manufacture, transportation, sale, or disposal of chemicals deemed to be toxic after testing procedures or according

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FURTHER READING

Gupta PK (2018) Illustrative Toxicology with Question bank. 1st Edition. Elsevier, USA

Gupta PK (2016) Fundamentals of Toxicology: Essential concepts and applications. 1st Edition. ISBN-9780128054260, pp 438, BSP/Elsevier, USA

The Merck Veterinary Manual (2016). Chapter “Herbicide Poisoning” by PK GUPTA 11^th edition, Merck & Co. Inc Whitehouse Station, NJ, USA  2969-99

The Merck Veterinary Manual (2016). Chapter “Pentachlorophenol Poisoning” by PK GUPTA 11^thedition, Merck & Co. Inc Whitehouse Station, NJ, USA  pp 3052-53

Gupta PK (2016) Essential Concepts in Toxicology. Published by PharmaMed Press (A unit of BSP Books Pvt. Ltd), Hyderabad, India pp 362.

Gupta PK (2010) Modern Toxicology, Basis of organ and reproduction toxicity. Vol 1. Published by Pharma  Med Press (A unit of BSP Books Pvt. Ltd). Hyderabad, India pp 1-460.

Gupta PK (2010) Modern Toxicology, Adverse effects of xenobiotics. Vol 2, Published by PharmaMed Press (A unit of BSP Books Pvt. Ltd). Hyderabad, India pp 1-460.

Gupta PK (2010) Modern Toxicology, Immuno and clinicsal toxicology Vol 3. Published by PharmaMed Press (A unit of BSP Books Pvt. Ltd). Hyderabad, India pp 1-340.

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