What was the original ambient air quality standard for lead in 1978?
1.5 micrograms/ m^3
what was ambient air quality standard of lead lowered to in 2008
0.5 micrograms/ m^3
What is the most abundant toxic heavy metal?
lead
Uses and sources of lead
- Paint
- Gas
- Household and ceiling dust
- Occupational
- Solder**
- Ceramic glazes**
- Pesticides
- Cigarettes
- Mines, smelters**
What has happened to the blood levels for lead consumed from gasoline and air over time?
decreased
There has been an ___ in lead in paint and in the air and gasoline since 1960.
increase
What are some ways that lead penetrates the human body?
- Inhaled
- Ingested
- Absorbed through skin
Lead goes down the __ and __ absorption pathways.
Fe and Ca
Where does most of lead go in the body?
- Mostly long bones
- 4% brain, liver, kidneys
- Crosses fetal blood-brain barrier
During which process is lead released in the body?
osteolysis (degeneration of bone from Ca loss)
Health effects of lead (2)
- Concentration related
- IQ/Delinquency related (dose-response)
What is causing lead poisoning in Nigeria?
- Gold mining
- Resulting in convulsions, neurological effects, blindness, deafness
exposure levels for to have a medical emergency from lead (children and adults)
child: > 50 ug/dL
adult: > 80 ug/dL
Exposure levels to have moderate effects from lead (children and adults)
child: > 25 ug/dL
Adult: > 60 ug/dL
exposure levels for children to have severe lead symptoms
55-70 ug/dL
What was the conclusion of the baby teeth study?
Higher doses of lead resulted in a shift in IQ and increase in learning disabilities.
Adverse effects on fetus from lead exposure
- Decreased gestational weight
- Decreased gestational age
- Miscarriage and stillbirth at very high levels of exposure
T/F Increased lead exposure is associated with inability to complete high school.
T
T/F Increased lead exposure is not associated with reading disability in young adulthood.
F
What are three consequences (behavioral) of lead kids?
- More delinquent
- More aggressive
- Bad attention spans
What has happened to the CDC’s action level of lead in blood in kids?
It has declined.
Which race and which gender are exposed to more lead, and get affected more?
African american, males
Sources of lead for babies and contribution amount
- Water and other: 10%
- Air: 15%
- Food: 20%
- Dust/Soil: 55%
% of kids entering public schools that have been lead poisoned
5%
