ENV MED - QUIZ 5, (WK6) , LEAD EXAM WITH 100% CORRECT
VERIFIED ANSWERS UPDATED 2025/26 BEST GRADED A+ FOR
SUCCESS
Per NHANES Fourth Report data, the mean Whole Blood Lead level (BPb) for 5 year-olds in the
USA is 1.7 mcg/dL. The CDC also defines normal blood Lead as < 10mcg/dL. Yet, many serious
health effects are seen at blood Lead levels near or even below the mean. This is a public health
issue of stunning magnitude. Given the numbers of people affected, though, solutions are not
simple. Medical chelation therapy, for example, is not recommended until the child's BPb
reaches 45mcg/dL, unless the child is acutely symptomatic and their BPb is at least 25mcg/dL.
This leaves a vast population with the need for screening and less aggressive management.
False
True CORRECT ANSWERS
True
Regarding health effects at BPb levels well within the normal range, the following statement is
true:
In post-menopausal women, doubling BPb correlates with a doubling of the rate of diastolic
HTN starting at PbB > 1mcg/dL
Subjects with Chronic renal Failure with mean BPb = 3.4 mcg/dL had significant less progression
to Renal Failure than those with BPb > 4.9 mcg/dL
Significant cognitive deficits in children with BPb beginning below 5 mcg/dL
Every level of BPb studied down to 1 mcg/dL produces significant change in cognitive functions
and motor coordination in adults and children.
Though clear causality has not been established in each of these reports, nevertheless at least
one author has proposed the new normal BPb range be lowered to < 2 mcg/dL (Gilbert 2006
Neurotoxicology 27;693-701)
All of these statements are true in this context CORRECT ANSWERS
, ENV MED - QUIZ 5, (WK6) , LEAD EXAM WITH 100% CORRECT
VERIFIED ANSWERS UPDATED 2025/26 BEST GRADED A+ FOR
SUCCESS
All of these statements are true in this context
Lead enters our bodies via:
GI tract exposure, and by this route it is 10% absorbed
Transdermal absorption, and by this route it is up to 26% absorbed (and that included
elemental lead, and lead bound to ascorbate, oxide, and nitrate)
All of these statements about how lead enters our bodies are true.
Respiratory exposure, and by this route it is 40-50% absorbed CORRECT ANSWERS
All of these statements about how lead enters our bodies are true.
Lead from a single new exposure will have exited blood completely within 40-80 days, which is
why this dynamic movement of the toxicant is called the "slow pool". It will exit the blood
either by excretion (kidney, liver, skin/hair/sweat) or by entering a very long-term tissue
storage that is measured in years, which is why this long-tem storage is called the "fast pool".
True
False: the "slow" and "fast" terms are switched incorrectly, but if you switch them back then it's
all correct. CORRECT ANSWERS
False: the "slow" and "fast" terms are switched incorrectly, but if you switch them back then it's
all correct.
VERIFIED ANSWERS UPDATED 2025/26 BEST GRADED A+ FOR
SUCCESS
Per NHANES Fourth Report data, the mean Whole Blood Lead level (BPb) for 5 year-olds in the
USA is 1.7 mcg/dL. The CDC also defines normal blood Lead as < 10mcg/dL. Yet, many serious
health effects are seen at blood Lead levels near or even below the mean. This is a public health
issue of stunning magnitude. Given the numbers of people affected, though, solutions are not
simple. Medical chelation therapy, for example, is not recommended until the child's BPb
reaches 45mcg/dL, unless the child is acutely symptomatic and their BPb is at least 25mcg/dL.
This leaves a vast population with the need for screening and less aggressive management.
False
True CORRECT ANSWERS
True
Regarding health effects at BPb levels well within the normal range, the following statement is
true:
In post-menopausal women, doubling BPb correlates with a doubling of the rate of diastolic
HTN starting at PbB > 1mcg/dL
Subjects with Chronic renal Failure with mean BPb = 3.4 mcg/dL had significant less progression
to Renal Failure than those with BPb > 4.9 mcg/dL
Significant cognitive deficits in children with BPb beginning below 5 mcg/dL
Every level of BPb studied down to 1 mcg/dL produces significant change in cognitive functions
and motor coordination in adults and children.
Though clear causality has not been established in each of these reports, nevertheless at least
one author has proposed the new normal BPb range be lowered to < 2 mcg/dL (Gilbert 2006
Neurotoxicology 27;693-701)
All of these statements are true in this context CORRECT ANSWERS
, ENV MED - QUIZ 5, (WK6) , LEAD EXAM WITH 100% CORRECT
VERIFIED ANSWERS UPDATED 2025/26 BEST GRADED A+ FOR
SUCCESS
All of these statements are true in this context
Lead enters our bodies via:
GI tract exposure, and by this route it is 10% absorbed
Transdermal absorption, and by this route it is up to 26% absorbed (and that included
elemental lead, and lead bound to ascorbate, oxide, and nitrate)
All of these statements about how lead enters our bodies are true.
Respiratory exposure, and by this route it is 40-50% absorbed CORRECT ANSWERS
All of these statements about how lead enters our bodies are true.
Lead from a single new exposure will have exited blood completely within 40-80 days, which is
why this dynamic movement of the toxicant is called the "slow pool". It will exit the blood
either by excretion (kidney, liver, skin/hair/sweat) or by entering a very long-term tissue
storage that is measured in years, which is why this long-tem storage is called the "fast pool".
True
False: the "slow" and "fast" terms are switched incorrectly, but if you switch them back then it's
all correct. CORRECT ANSWERS
False: the "slow" and "fast" terms are switched incorrectly, but if you switch them back then it's
all correct.
