I now have sufficient content from the textbooks to compile a comprehensive set of MCQs. Let me compile the final answer.
Here is a comprehensive set of important MCQs from General Toxicology for university professional exams, drawn from:
- The Essentials of Forensic Medicine and Toxicology, 36th Edition (2026)
- P.C. Dikshit's Textbook of Forensic Medicine and Toxicology
- Parikh's Textbook of Medical Jurisprudence, Forensic Medicine and Toxicology
General Toxicology - MCQs for Professional Exams
SECTION 1: Definitions and Concepts
Q1. Toxicology is derived from the Greek word:
- A) Toxeon
- B) Toxon
- C) Toxicus
- D) Taxis
Answer: B - Toxon (meaning a bow used for shooting arrows; arrows were dipped in poison, hence "toxic")
- P.C. Dikshit's Textbook of Forensic Medicine and Toxicology
Q2. "Father of modern toxicology" is:
- A) Orfila
- B) Hippocrates
- C) Paracelsus
- D) Dioscorides
Answer: C - Paracelsus
He coined the principle: "All things are poison and nothing is without poison. It is the dose that determines the poison." He was the first to explain the dose-response relationship.
- P.C. Dikshit's Textbook of Forensic Medicine and Toxicology
Q3. Who is called the "Father of forensic toxicology"?
- A) Paracelsus
- B) Matthieu Orfila
- C) Robert Christison
- D) Tardieu
Answer: B - Matthieu Orfila (Spanish chemist, 1787-1853)
He was the first to attempt a systematic correlation between chemical and biological information of poisons, and devised methods for detecting poisons.
- The Essentials of Forensic Medicine and Toxicology, 36th Ed.
Q4. Which of the following best defines forensic toxicology?
- A) Science dealing with properties and actions of poisons
- B) Medical and legal aspects of harmful effects of chemicals on humans
- C) Study of toxins produced by living organisms
- D) Science of detecting poisons in urine
Answer: B
Forensic toxicology deals with the medical and legal aspects of harmful effects of poisonous/chemical substances on human beings.
- Parikh's Textbook of Medical Jurisprudence, Forensic Medicine and Toxicology
Q5. Toxinology deals with:
- A) Synthetic chemical poisons
- B) Toxins produced by living organisms - plants, animals, bacteria and fungi
- C) Radiation-induced toxicity
- D) Narcotic drug analysis
Answer: B
Toxinology is the science that deals with biological toxins such as venoms, poisonous plants, and bacterial/fungal toxins.
- P.C. Dikshit's Textbook of Forensic Medicine and Toxicology
Q6. The legal difference between a medicine and a poison depends on:
- A) The dose administered
- B) The route of administration
- C) The intent with which it is given
- D) The chemical composition
Answer: C - Intent
In law, if a substance is given with the intention to save life, it is a medicine; if given with intention to cause bodily harm, it is a poison.
- Parikh's Textbook
Q7. LD50 is defined as:
- A) Lethal dose for 100% of animals
- B) Lethal dose for 5% of animals
- C) Dose that kills 50% of the test population
- D) Minimum lethal dose in humans
Answer: C
LD50 is the dose of a toxic substance that kills 50% of a test population (typically rats or other surrogates for human toxicity studies).
- P.C. Dikshit's Textbook of Forensic Medicine and Toxicology
SECTION 2: Classification of Poisons
Q8. Poisons are classified as corrosive when they:
- A) Act on the nervous system
- B) Cause local destruction of tissue at the site of contact
- C) Produce systemic effects only
- D) Are volatile substances
Answer: B - Corrosives cause local destruction/charring of tissues at the site of contact.
Q9. Which of the following is a corrosive acid poison?
- A) Arsenic
- B) Phosphorus
- C) Sulphuric acid
- D) Mercury
Answer: C - Sulphuric acid
Strong inorganic/mineral acids - sulphuric acid, nitric acid, hydrochloric acid - are classified as corrosives.
- P.C. Dikshit's Textbook
Q10. Carbolic acid (phenol) is classified as:
- A) Inorganic corrosive
- B) Organic corrosive acid
- C) Metallic irritant
- D) Neurological depressant
Answer: B - Organic corrosive acid
Organic acids classified as corrosives include: carbolic acid, oxalic acid, acetic acid, and salicylic acid.
- P.C. Dikshit's Textbook
Q11. Which of the following is an irritant metallic poison?
- A) Strychnine
- B) Arsenic
- C) Hydrochloric acid
- D) Opium
Answer: B - Arsenic
Irritant inorganic metallic poisons include: Arsenic, Lead, Mercury, Copper, Zinc, Thallium.
- P.C. Dikshit's Textbook
Q12. Which non-metallic element is classified as an irritant poison?
- A) Sulphuric acid
- B) Carbolic acid
- C) Phosphorus
- D) Arsenic
Answer: C - Phosphorus
Non-metallic irritant poisons include: Phosphorus, Chlorine, Bromine, Iodine.
- P.C. Dikshit's Textbook
Q13. Aluminium phosphide is commonly used as:
- A) Rat poison
- B) Grain preservative / suicidal poison
- C) Homicidal poison
- D) Disinfectant
Answer: B - Grain preservative, and it is also commonly used for suicide.
Zinc phosphide is the rat poison. Aluminium phosphide is the grain preservative.
- P.C. Dikshit's Textbook
SECTION 3: Types of Poisoning and Medicolegal Aspects
Q14. In acute poisoning:
- A) Small amounts are taken repeatedly over a long period
- B) Effects manifest between acute and chronic types
- C) Whatever amount of poison is taken, toxicity manifests immediately
- D) Only metallic poisons cause this
Answer: C
Acute poisoning: the amount taken produces toxicity that manifests immediately.
- P.C. Dikshit's Textbook
Q15. Substances commonly causing CHRONIC poisoning include:
- A) Strychnine, cyanide, CO
- B) Lead, mercury, opium, antimony
- C) Organophosphates, carbamates
- D) Sulphuric acid, nitric acid
Answer: B - Lead, mercury, opium, antimony
Chronic poisoning occurs with repeated small doses over a long period; common substances are metallic poisons, opium, and antimony.
- P.C. Dikshit's Textbook
Q16. The ideal homicidal poison should be:
- A) Coloured, tasteful, and rapidly acting
- B) Colourless, tasteless, odourless with slow onset resembling natural disease
- C) Easily available and cheap
- D) Producing obvious postmortem changes
Answer: B
The ideal homicidal poison: colourless, tasteless, odourless, slow onset, symptoms resembling natural disease, no postmortem changes, no antidote, highly toxic.
- P.C. Dikshit's Textbook
Q17. Arsenic, antimony, aconite, and strychnine are examples of:
- A) Suicidal poisons
- B) Homicidal poisons
- C) Accidental poisons
- D) Industrial poisons
Answer: B - Homicidal poisons
- P.C. Dikshit's Textbook
Q18. Sections of IPC dealing with offenses related to administration of poisons include:
- A) Sections 201, 202, 203
- B) Sections 284, 299, 300, 304A, 324, 326, and 328
- C) Sections 174, 175, 176
- D) Sections 100, 101, 102
Answer: B - Sections 284, 299, 300, 304A, 324, 326, 328 IPC
- Parikh's Textbook
SECTION 4: Factors Modifying the Action of Poisons
Q19. Which factor most importantly modifies the toxic action of a poison?
- A) Colour of the poison
- B) Quantity/dose
- C) Time of day it is taken
- D) Weather conditions
Answer: B - Quantity/Dose
The principle that "the dose makes the poison" (Paracelsus) is fundamental. Toxic effects vary with the quantity administered.
- P.C. Dikshit's Textbook
Q20. Methyl alcohol (methanol) is toxic because:
- A) It directly poisons mitochondria
- B) It is converted to toxic formaldehyde by liver enzymes
- C) It blocks acetylcholinesterase
- D) It chelates heavy metals
Answer: B - Converted to toxic formaldehyde in the liver
Many substances are toxic only indirectly; methanol itself is not poisonous but is chemically converted to formaldehyde (and formate) by the liver.
- P.C. Dikshit's Textbook
SECTION 5: Decontamination and General Management
Q21. The universal antidote/adsorbent used in poisoning management is:
- A) Potassium permanganate
- B) Sodium bicarbonate
- C) Activated charcoal
- D) Naloxone
Answer: C - Activated charcoal
Activated charcoal is the primary GI decontaminant in poisoning, adsorbing a wide range of toxins.
- Tintinalli's Emergency Medicine; The Essentials of Forensic Medicine and Toxicology, 36th Ed.
Q22. Routine gastric lavage in poisoning:
- A) Should be done in all cases within 6 hours
- B) Is no longer recommended as a routine procedure
- C) Is preferred over activated charcoal
- D) Should be performed before airway protection
Answer: B - Not recommended as a routine procedure
According to current guidelines (American Academy of Clinical Toxicology), routine gastric lavage is not recommended; it is considered only for life-threatening ingestion of a poison not adsorbable by charcoal.
- ROSEN's Emergency Medicine; Tintinalli's Emergency Medicine
Q23. Ipecac syrup (to induce emesis) in poisoning:
- A) Is the treatment of choice for all oral poisons
- B) Should be given before gastric lavage
- C) Is no longer recommended
- D) Is preferred in corrosive poisoning
Answer: C - No longer recommended
Ipecac syrup to induce emesis is not recommended in current poisoning management protocols.
- Tintinalli's Emergency Medicine
Q24. Multiple-dose activated charcoal (MDAC) is especially used after ingestion of:
- A) Immediate release preparations
- B) Extended-release (ER) preparations
- C) Corrosive acids
- D) Petroleum distillates
Answer: B - Extended-release (ER) preparations
- Tintinalli's Emergency Medicine
SECTION 6: Specific Toxicokinetics and Drug Laws
Q25. The Narcotic Drugs and Psychotropic Substances (NDPS) Act was passed in:
- A) 1940
- B) 1960
- C) 1985
- D) 1995
Answer: C - 1985
The NDPS Act 1985 repealed the Opium Act 1857, Opium Act 1878, and Dangerous Drugs Act 1930. It lists 77 psychotropic substances including LSD, barbiturates, benzodiazepines, ketamine, etc.
- The Essentials of Forensic Medicine and Toxicology, 36th Ed.
Q26. Under the NDPS Act 1985, which of the following is classified as a narcotic drug?
- A) Aspirin
- B) Paracetamol
- C) Cannabis
- D) Warfarin
Answer: C - Cannabis
Narcotic drugs under NDPS Act include: Cocoa leaf, Cannabis, Opium, Poppy straw, and all manufactured drugs derived from them.
- The Essentials of Forensic Medicine and Toxicology, 36th Ed.
Q27. Clinical toxicology is defined as:
- A) Medical and legal aspects of chemical harms
- B) Human diseases caused by or associated with abnormal exposure to chemical substances
- C) Science of biological toxins
- D) Analytical method of detecting poisons
Answer: B
Clinical toxicology deals with human diseases caused by, or associated with, abnormal exposure to chemical substances.
- The Essentials of Forensic Medicine and Toxicology, 36th Ed.
Q28. The Dioscorides classification of poisons was considered the standard for how many centuries?
Answer: C - 16 centuries
Dioscorides, a Greek physician in the court of Emperor Nero, attempted a classification of poisons which remained standard for sixteen centuries.
- The Essentials of Forensic Medicine and Toxicology, 36th Ed.
Q29. Which poison in a household matchbox causes matchstick poisoning?
- A) Zinc chloride
- B) Phosphorus, antimony, silicates, potassium chlorate
- C) Boric acid
- D) Naphthalene
Answer: B
Matchbox/sticks contain silicates, antimony, phosphorus, and potassium chlorate; poisoning manifests as symptoms of antimony and phosphorus toxicity.
- P.C. Dikshit's Textbook
Q30. Baby powder poisoning is caused by:
- A) Talc
- B) Boric acid
- C) Zinc oxide
- D) Titanium dioxide
Answer: B - Boric acid
Baby powder contains boric acid; poisoning produces nausea, vomiting, diarrhoea, convulsions, and respiratory depression.
- P.C. Dikshit's Textbook
Quick Reference Summary Table
| Topic | Key Fact |
|---|
| Father of modern toxicology | Paracelsus |
| Father of forensic toxicology | Matthieu Orfila |
| "Dose makes the poison" | Paracelsus, 16th century |
| LD50 | Dose killing 50% of test population |
| Corrosive acids | H2SO4, HNO3, HCl (inorganic); Carbolic, Oxalic (organic) |
| Metallic irritants | Arsenic, Lead, Mercury, Copper, Zinc, Thallium |
| NDPS Act | 1985; replaced Opium Acts of 1857, 1878 & Dangerous Drugs Act 1930 |
| Universal adsorbent | Activated charcoal |
| Routine gastric lavage | NOT recommended (current guidelines) |
| Grain preservative poison | Aluminium phosphide |
| Rat poison | Zinc phosphide |
| Chronic poisons | Lead, mercury, opium, antimony |
These 30 MCQs cover all standard exam topics in General Toxicology: definitions, history, classification, factors modifying action, medicolegal aspects, and management principles. Sources: The Essentials of Forensic Medicine and Toxicology (36th Ed., 2026), P.C. Dikshit's Textbook of Forensic Medicine and Toxicology, Parikh's Textbook of Medical Jurisprudence, Forensic Medicine and Toxicology.