Environmental Toxins and Pollutants Flashcards
Lethal dose of cyanide
1mg/kg body wgt
Lethal dose of morphine
25mg/kg bw
Lethal dose of aspirine
500mg/kg bw
Lethal dose of ethyl alcohol
10g/kg bw
Effects of corrosives
- remove water from tissues
- coagulate cellular proteins
- convert Hb to acid hematin
cause circulatory collapse and spasm of glottis
H2SO4 in gastric fluid can be detected by
reacting with BaCl2 to form white ppt of BaSO4
NH3, KOH, NaOH in gastric fluid can be detected by
reacting with AgNO3 to form brown ppt of AgOH
Sources of cyanide poisoning
- suicide attempts
- exposure to prussic acid
- ingestion of amygdalin in kernels of apricots, peaches
Effects of cyanide poisoning
- chelates ferric ions of cytochrome oxidase
- causes tissue anoxia
Antidotes for cyanide poisoning
- Dicobalt Edetate chelates cyanide
- Na nitrate converts Hb to Met Hb which takes up CN
- Na thiosulfate detoxifies CN to thiocyanate for excretion
Phosphorous toxicity
- affects cellular oxidation
- chewing fireworks or rat poison
- symptoms similar to acute liver disease
Sources of lead poisoning
- Paint
- Lead pipes
- Newspapers
- Cigarettes
- Lead chromate adulterant in curcumin
- Batteries
Toxic limit of lead
10mg/dl in children
25mg/dl in adult
Symptoms of lead poisoning
In fetuses 1. Miscarriage 2. Stillbirth 3. Premature birth In developing brains 1. Neurological sequelae 2. Cerebral palsy 3. Optic atrophy In children 1. MR 2. Learning disabilities 3. Behavioural problems 4. Hyperexcitability 5. Seizures
Symptoms of acute toxicity of lead
> 70mg/dl
- Encephalopathy
- Convulsions
- Mania
- Neuropathy
- Abdominal colic
- Anaemia
- DISCOLOURATION AND BLUE LINES ALONG GUMS
Physiological effects of lead poisoning
- Inhibits heme synthesis
- Basophilic splitting of RBC
- Agglutination of ribosomes
- Inhibits ALA synthetase and dehydratase
Antidote for lead poisoning
Dimercaptosuccinic acid
Dimercaprol
Pencillamine
Calcium dodecyl edetate
Symptoms of elemental mercury poisoning
Acute - pulmonary edema, encephalopathy
Chronic - oral lesions, tremors, memory loss, insomnia
Toxic limit of mercury poisoning
toxic - 2-5mg/dl
fatal - >15mg/dl
Antidote for mercury poisoning
Dimercaprol derv.
D penicillamine
Symptoms of severe cases of organic mercury poisoning
- Toxic encephalopathy
- Sensory neuropathy
- Intention tremor
- Hearing loss
- Spasticity
Symptoms of methyl mercury exposure
- Dysarthria
- Ataxia
- Visual field constriction
Intake limit for Al
100mg/day
Effects of ALuminium toxicity
- stimulates free radical production
- prevents Ca, P, Fe absorption
- Interferes with heme synthesis
- Precipitates Alzheimers protein
- Degeneration of dendrites
- Parkinsons
Symptoms of Al toxicity
- osteomalacia
- microcytic hypochromic anaemia
Effect of arsenic toxicity
Acts on sulfahydryl enzymes and interferes with cell metabolism
Symptoms of arsenic toxicity
- Intravascular haemolysis
- Agranulocytosis
- Hepatitis
- Jaundice
- Encephalitis
Effect of DDT
Depressed spermatogenesis and fertility
Effect of organophosphorous compounds
prevents transmission of nerve impulses by inhibiting AChesterase
Effect of polychlorobiphenyls
- decrease fertility
- behavioural changes
symptoms of methanol toxicity
- optic neuritis
- blindness
Treatment for methanol toxicity
large doses of ethanol given so that it is preferentially oxidised
Lathyrism
- Scissor gait
- Ankle clonus
- Exaggerated knee jerk
- Spastic paralysis of lower limbs
Toxin - Beta oxalyl amino alanine which inhibits lysyl oxidase to prevent cross linking in collagen
Keshari Dal
Argemone oil
- Vomiting
- Diarrhoea
- Congestive cardiac failure
- Edema
Toxin- Sanguinarine
Mustard oil adulteration
