Toxicology Flashcards
What causes pesticide poisoning
ACHE I poisoning happen due to organophosphates - seen in farmers
Pesticides poisoning symptoms
DUMBBELSS Diarrhea Urination Miosis Bronchospasm Bradycardia Emesis Lacrimation Sweating Salivation
What are the nicotinic and CNS symptoms of pesticides poisoning
Nicotinic-> weakness paralysis and fasiculations
CNS—> seizures, respiratory depression and coma
Pesticides poisoning treatment
Atropine -> reverses muscarinic and crosses bbb to reverse CMS
Pralidoxime—> reactivates aches reversing muscarinic and nicotinic symptoms but doesn’t cross BBB
Where is methanol found
In cleaning products
What happens to methanol when it’s ingested
It’s metabolised to formaldehyde and fromic acid
What does methanol metabolites do
They are toxic to the eye and cause blindness, CNS depression-> coma
How does poisoning with ethylene glycol present
Presents with acute renal failure
Where is ethylene glycol found
Automobile antifreeze and engine coolant
What happens to ethylene glycol after it enters the body
It is metabolised to glycolic acid which is toxic to the renal tubules and OXALIC ACID can precipitate with calcium forming calcium oxylate score in the renal tubule
What does calcium oxylate do to the renal tubules
Causes metabolic acidosis and renal failure
What’s the antidote to methanol and ethylene glycol
Fomepizole blocking ADH
Usual case of lead poisoning
Child injesting lead containing paint chips or adult inhale in lead mines or frequent contact with batteries and bullets
What does lead do in the body
Lead inhibits two enzymes in HEME SYNTHESIS -> leading to anemia
-enzymes are
ALA dehydratase
Ferrochelatase
Lead positioning symptoms
Congenitive delays and behavioural changes in children drop in IQ
Short term memory loss, lead palsy(foot drop and wrist drop) in adults
Effect of lead on pregnant women
Can cause miscarriage, prematurity and can get excreted in breast milk
Lead poisoning treatment
Chelating agents
succimer for children
Dimercaprol or EDTA for adults
Effect of mercury poisoning on pregnant women
It’s Teratogenic so we should avoid it in pregnant women
How does mercury poisoning happen usually
Occurs from eating sea food and emissions from coal fired planets
Mercury poisoning symptoms
It’s neurotoxic so leads to anxiety, irritablity and tremors
Causes acrodynia pink disease -> pink hands and feet
Mercury poisoning treatment
Chelating agents like
EDTA and dimercaprol
How do we get cadmium poisoning
Ingestion of contaminated sea food
Cadmium uptake from plants
Inhalation of smoke cigs
What happens when cadmium is invested
Can lead to kidney failure, liver damage, osteoporosis and itai itai disease
What happens when cadmium is inhaled
It causes renal failure and decrease in lung function it can also lead to cancer cells as it produces reactive oxygen species
Cyunide and CO poisoning how do they affect the body
They bind and inhibit enzymes containing iron ( cytochrome C oxidase complex IV of ETC) -> inhibiting ATP production—> so anaerobic glycolysis takes over causing increase level of lactic acid and metabolic acidosis
How does cyanide poisoning happen
Inhaling of smoke from burning synthetic product or ingesting of amygdalin (apricot seed)
Cyanide poisoning characteristic
Bitter almond breath odor, mydriasis, seizures and cardiac arrest
Cyanide poisoning treatment
- Activated charchol
- Sodium thiosulfate inducing methemoglobin production which binds is to cyanide
- hydroxocobalamin which binds to cyanide
What is CO called and why
Silent killer- colourless odourless and tasteless
How does CO poisoning happen
Inhalation of too much CO, close to the fire inhaling smoke (fireplace) -> multiple individuals may develop symptoms at the same time
What does CO do in the blood
It binds to Hb displacing O2 as it has higher affinity
Co poisoning symptoms
Headache, nausea, seizures, coma and cherry red rash
CO poisoning treatment
High flow 100% O2 ASAP
What are Benzene and toluene
Aromatic hydrocarbons
What can aromatic hydrocarbons do
They are volatile, can cross BBB so cause CNS toxicity
How can toluene and benzene by obtained
From solvent vapours
What can benzene cause
Acute myeloid leukaemia
Anaplastic anemia
What can toluene cause
CNS depression
What are the characteristics of halogenated hydro carbons
Same as aromatic hydrocarbons
They are volatile, can cross BBB so cause CNS toxicity
Where are halogenated hydrocarbons found
They are found in refrigerants, propellants and cleaning products
What does chloroform do
Depletes glutathione (antioxidant) causing necrosis of renal cells and hepatocytes
What substitutes glutathione
Nacetylcysteine substitutes glutathione
What can carbon tetracholride do
Generation of ROS. Causing necrosis
What is chloroform and carbon tetrachloride
Halogenated hydrocarbons
What happens when asbestos is inhaled
Leads to asbestosis -> fibrosis and calcification of the lung
What type of cancer can asbestos cause
Lung and mesothelioma
What happens when inhaling silica
Silicosis
Where does silica exposure happen
Mines and stone cuttings - prolonged exposure in to silica industries
Silicosis
Progressive irreversible fibrotic lung disease - COPD
When do we use chelators
Only use when needed as they have serious side effects and only used with metal poisoning
Side effects of EDTA
Given IV or IM can cause reversible renal damage
What is dimercaprol used for
Used to chelate mercury
Dimercaprol + EDTA uses
For lead
Dimercaprol die effects
Increase blood pressure and heart rate ohhh
What is DMPS (unithiol)
Dimercaprol derivative- less toxic
What is succimer
Derivative of dimercaprol - less toxic given orally - doesn’t cause increase in BP and HR
What doesn’t succimer chelate
Zinc copper and iron
