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Elevated Blood Lead Levels: Statistical Analysis Meets Social

Phenomena

Ronnie Levin, Region 1Ronnie Levin, Region 1Barry D. Nussbaum, OEIBarry D. Nussbaum, OEI

U.S. Environmental Protection AgencyU.S. Environmental Protection Agency

Presented to: EPA Quality

Management Conference

May 14, 2009

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Lead has thousands of commercial applications

• Octane booster for gasoline• Radiation shields• Sheathing for cables• Solder: plumbing, stained

glass, electronics• Pigments: glazes, paint,

newspaper ink• Fine crystal

• Pesticides & plant growth regulators

• Hair preparations• Water pipes• Automobile batteries• Fishing & diving

weights• Stabilizer in plastics

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Lead in Gasoline and in Blood

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The good news

1974 1976 1978 1980 1982 1984 1986 1988 1990 1992 1994 1996 1998

Year1972

Blo

od

Lea

d L

evel

s (µ

/dL

)

18

2

4

6

8

10

12

14

16

0

18

2

4

6

8

10

12

14

16

0

2000

Impact of Lead Poisoning Prevention Policy on Reducing Children’s Blood Lead Levels

Lead Gasoline

Phase-out (1973)

Lead-based Paint Poisoning Prevention Act (1971)

Residential Lead Paint Ban (1978)

Lead Title X (1992)

Housing units with lead based paint

hazards reduced by 40% since 1990

Lead Contamination Control Act (1988)

Virtual Elimination of Lead in Gasoline

Ban on lead solder in food cans(1995)

Lead in Plumbing banned (1986)

2002

Average BLLs of US Children, 1972-2002

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Risk factors for elevated BLLs

• Age

• Season

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More risk factors

• Income– Income, Medicaid vs private insurance, own-

rent home, # people in household,

• Race & ethnicity

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More risk factors

• Age of housing

• Location of residence– Children (1-5) in the 10 largest cities

accounted for 46% of EBLs in 2003 but only 7% of the population that age

• Parental occupation

• Smoking

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We knew the job wasn’t finished…

• Landrigan et al (’02) estimated that residual benefits of reducing blood lead levels of children born in 1997 were $43.4 billion annually (present value) considering only reduced lifetime earnings

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And we knew we had more problems

• 30% of EBLs don’t have a proximate lead-paint source– 5-20% don’t have ANY identified source

• Number of EBLs in Manchester NH doubled between 1997 and 2004

• Imported lead-contaminated goods, and especially toys

• DC kids’ BLLs didn’t decrease after 2001• 20% of ayurvedics have dangerous PB levels

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13

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What are the new Pb exposure frontiers?

• Paint• Soil and dust• Ethnic imports (foods, remedies, cosmetics,

pottery & cooking utensils)• Immigrants• Parental occupational exposures• Inadequately monitored foreign goods (paint,

toys, consumer goods)• Public drinking water

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These are airports servicing general aviation aircraft of which ~80% are piston engine aircraft using leaded avgas

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What does this all mean?

• Focusing on lead paint or even LBP where there is an EBL ISN’T ENOUGH

• Need cooperation across federal, state and local governments

• Need to control/eliminate Pb exposures BEFORE children are exposed– Primary prevention

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But all is not lost in data analysisBut all is not lost in data analysis Data was compiled from 5 different sources

NHANES - National Health and Nutrition Examination Survey (CDC) TRI – Toxic Release Inventory (EPA) AirData – Summary of AQS and NEI (EPA) CBLS – Childhood Blood Lead Surveillance Program (CDC) 2000 United States Census (Census Bureau)

CombinedDataset

NHANES(CDC)

CBLS(CDC)

TRI(EPA)

2000 U.S.Census Data

2000 U.S.Census Data

*Analyzed separately due to privacy concerns

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BackgroundBackgroundJoshua Drukenbrod and Chad Harness (Fall 2007)

Industry Stand-Outs (NHANES) Construction Mfg. metal industries

Occupation Stand-Outs (NHANES) Farm and nursery workers Vehicle/mobile equp. Mechanics Construction trade Construction laborers

Origin Stand Out (NHANES) Born in Mexico try Stand-Outs (NHANES) Construction Mfg. metal industries Repair services

Occupation Stand-Outs (NHANES) Farm and nursery workers Vehicle/mobile equp. Mechanics Construction trade Construction laborers

Origin Stand Out (NHANES) Born in Mexico

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BackgroundBackground

Steven Somers, Jessica Williams (Fall 2007), and

Amanda Cambell (Spring 2008)

California, 2003 /2006 disparity: Compared 2003 and 2006 California data Determined the integrity of the 2006 data Found new significant variables

Correlation between EBLL rates and: Poverty rates in children under 6 Percent Pre-1950 homes Percent Hispanic Percent Agriculture

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What we learned from calling the What we learned from calling the states/countiesstates/counties……

Nevada (does not report to CDC)• Started the program in 2006, therefore they don’t have a 3 year cohort necessary

for reporting to the CDC

• They only data for Clark County

• When they find elevated levels, they make parents fill out an extensive, 22-page survey

Illinois (underestimated data on CDC web-site)• Where the family lives while their house is being remediated is dependent upon the

lead investigator

• When data is submitted to the CDC with missing information (i.e. address, city, etc.) the data is thrown out

• Requires a follow-up test for any child who tests with an EBLL

Wisconsin (had high levels in Milwaukee)• Found that window sills have the highest levels of lead in them

• Have begun a prevention plan where all window sills are being replaced in older homes

1/3 of the homes have been remediated and the average EBLL rate has dropped from 31.9% to 5.9% in the past 10 years

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What we learned from calling the What we learned from calling the states/countiesstates/counties……

Pennsylvania• Pennsylvania is a targeted screening state

• Some states test all 1 & 2 year old children (universal testing), and one can expect to find far fewer elevated results (proportionately) in such a large sample as compared to a state that target testing to high risk areas only

Cuyahoga, OH• Federal law states that all children under the age of 3 who are on Medicaid must have

their lead level tested

• Occupation of parents: Child got lead poisoning from father’s shooting range clothes

• “Some parents would rather not know if their child has an EBLL because they fear eviction.”

Kathy Shack, Cuyahoga County Official

Denver, CO• Jane Mitchell, an Environmental Health Research Scientist for the Colorado

Department of Health and Environment, informed us that the original data submitted by CO was incorrect and has since sent us the correct EBLL data

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VariablesVariables Variables:

• % pre-1980 housing

• % population African American

• % population Hispanic

• % work force in agriculture

• % work force in construction

• % work force in manufacturing

• % work force in transportation

• % work force in education/health services

• TRI data

• Air Data

• Rural/Urban

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AnalysisAnalysis of North East Regionof North East Region

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