Toxicology: Heavy Metals and Chelators

Question 1

found in:
* Storage batteries, ammunition,
* metal alloys, solder, glass,
* plastics, pigments and
* ceramics

Answer 1

Lead

Question 2

TRUE OR FALSE: Lead has no useful purpose in the human body

Answer 2

true

Question 3

lead is absorbed ____ but consistently via the _____ and _____

Answer 3

slowly; respiratory and gastrointestinal tract

Question 4

how much lead is absorbed in children

Answer 4

50%

Question 5

how much lead is absorbed in adults

Answer 5

10-15%

Question 6

TRUE OR FALSE: Lead has poor absorption in the skin

Answer 6

true

Question 7

Lead is ___% bound to RBCs, ___% free in
plasma

Answer 7

99% bound to RBCs, 1% free in
plasma

Question 8

Lead is distributed through the ____

Answer 8

bone marrow, brain, kidney, liver, muscle and gonads; then bones

Question 9

TRUE OR FALSE: Lead crosses the pancreas

Answer 9

false, placenta

Question 10

half life of lead

Answer 10

1-2 months

Question 11

Half life of lead in bones

Answer 11

years to decades

Question 12

how much lead is excreted in urine

Answer 12

70%

Question 13

Lead and arsenic inhibits ____

Answer 13

enzymatic function

Question 14

what cations does lead interfere

Answer 14

calcium, zinc, iron

Question 15

causes Oxidative stress generation

Answer 15

Lead and Arsenic

Question 16

causes Gene expression changes

Answer 16

Lead and Arsenic

Question 17

causes Cell signaling alteration

Answer 17

Lead and Arsenic

Question 18

causes Disruption of membrane integrity

Answer 18

Lead and Arsenic

Question 19

TRUE OR FALSE: Lead causes low bp

Answer 19

False, high bp

Question 20

what are the Major Forms of Lead Intoxication

Answer 20

Inorganic Lead Poisoning and Organolead Poisoning

Question 21

what kind of lead (organic/inorganic) travels through skin, GI, and respiratory

Answer 21

organic, inorganic is GI and respiratory only

Question 22

major findings in organic lead

Answer 22

Encephalopathy

Question 23

what kind of lead (organic/inorganic) has clinical findings of CNS deficits; peripheral neuropathy; anemia; nephropathy; hypertension; reproductive toxicity

Answer 23

inorganic

Question 24

what kind of lead (organic/inorganic) Inhibits enzymes; interferes with essential
cations; alters membrane structures

Answer 24

inorganic

Question 25

inorganic lead metabolize and eliminate in ___

Answer 25

Renal (major); feces and breast milk (minor)

Question 26

organic lead metabolize and eliminate in ___

Answer 26

Urine and feces (major); Sweat (minor)

Question 27

treatment for lead and arsenic

Answer 27

chelation therapy

Question 28

what is chelation therapy medium, dose, and duration for lead poisoning

Answer 28

Intravenous edetate calcium disodium (CaNa 2 EDTA) at a dosage of 30-50mg/kg/d by continuous infusion for up to 5 days only

Question 29

Oral Succimer (DMSA) is given after __ days

Answer 29

5 days

Question 30

Retained lead objects require ___

Answer 30

gastrointestinal decontamination

Question 31

Semiconductors, wood preservatives, nonferrous alloys, glass and turf herbicide monosodium methane arsonate (MSMA)

Answer 31

Arsenic

Question 32

arsenic is absorbed in ___

Answer 32

respiratory and GIT

Question 33

TRUE OR FALSE: percutaneous absorption of lead is limited

Answer 33

false, arsenic

Question 34

____ is Metabolized by the liver via methylation reactions

Answer 34

Arsenic

Question 35

where is arsenic excreted

Answer 35

Excreted in the Urine (major), sweat and feces

Question 36

distribution of arsenic

Answer 36

Predominantly soft tissues (highest in liver and kidney). Tightly bound to skin, hair and nails

Question 37

TRUE OR FALSE: arsenic causes encephalopathy

Answer 37

true

Question 38

Metabolism and Elimination of arsenic

Answer 38

Methylation; Excreted via Urine (major), Sweat and Feces (minor)

Question 39

Hyperpigmentation and hyperkeratosis involving hands and feet Usually due to chronic inorganic arsenic poisoning

Answer 39

Raindrop pattern”

Question 40

what is chelation therapy medium, dose, and duration for acute arsenic poisoning

Answer 40

Chelation with Unithiol 3 5mg/kg every 4-6 hours or Dimercaprol every 4-6 hours

Question 41

Quicksilver or liquid metal

Answer 41

Mercury

Question 42

found in Electrolytic production of chlorine and caustic soda; electrical equipment, thermometer, instruments, fluorescent lamps; dental amalgams; artisanal gold production

Answer 42

Mercury

Question 43

Absorbed from the lungs, GI tract, and percutaneous route

Answer 43

Mercury

Question 44

where is mercury most concentrated

Answer 44

kidneys

Question 45

mercury is excreted via

Answer 45

urine and feces

Question 46

major routes of elemental mercury

Answer 46

Respiratory tract

Question 47

major routes of inorganic mercury

Answer 47

GI, skin (minor)

Question 48

major routes of organic mercury

Answer 48

GI, skin, respiratory tract (minor)