what is toxicology

Question 1

what is toxicology

Answer 1

the study of adverse/undesirable effects of substances on living systems

Question 2

give an example of plants that could cause accidental poisoning

Answer 2

• deadly nightshade (atropine, muscarinic antagonist) scopolamine less selective antagonist, also acts on histamine receptors so it inhibits gastric secretions
• woody nightshade (solanine, inhibits cholinesterase) also found in small amnt tomato and green potatoes
  -calabar beans (physostigmine, inhibits cholinesterase)

Question 3

give examples of toxins that could occur in food

Answer 3

puffer fish (tetrodotoxin)
infected rye (ergot alkaloids)
cassava/bitter almonds (cyanide)
kidney beans (lectins)
mouldy apples (patulin)

Question 4

give an example of a toxin that was used maliciously historically

Answer 4

hemlock- CNS and neuromuscular junction nicotinic receptor blocakde (coniine)
-ricin
-dioxin
-phosgene
-mustard gas
-lewisite
-nerve agent VX
-Sarin
-novichok

Question 5

give examples of occupational toxicology

Answer 5

scheele green color wallpaper (copper arsenite)

enviornmental arsenic pollution due to mining

paraquat (herbicide) poisoning in agricultural workers

diazinon and malathion (organophosphates that inhibit acetylcholinesterase) agricultural workers

Question 6

outline the role of toxicology in pharmacology (how it is useful and pharmaceuticals that are toxic)

Answer 6

useful:
-deliberate poisoning via anti-cancer agents
-deliberate but selective: anti microbials anti virals anti fungals
-helps find cures to toxic ingredients ex: NAC antidote for paracetamol poisoning ex: dimercaprol (heavy metal and lewisite poisoning)

toxic:
-paracetamol (liver toxicity)
-halothane (allergic hepatitis)
-thalidomaide (birth defects)
-terfenadine (H1 antagonist causes QT prolongation and cardiac arrest)