Hazard 7: Lead
Housing Health and Safety Rating
System
2012 1
Potential for Harm
• The most vulnerable age group is children
under six years old.
– This is because of potential effects on neurological
development, and because young children’s
bodies more readily take up lead.
• Other risk groups include pregnant women
and fetuses.
2012 2
Relevant Matters Affecting Likelihood and Harm Outcome
1. Date of construction – Dwellings constructed before 1978 may contain lead based paint (LBP).
– 24% of houses built from 1960-1978 contain LBP.
– 69% of houses built from 1940-1960 contain LBP
– 87% of houses built before 1940 contain LBP.
2. Disrepair to Lead Based Paint– Damage and/or flaking of old paintwork leads to possible ingestion of lead dust and lead-
containing paint chips.
– Lack of heat can cause increased deterioration
– Lack of water can cause inability to wet clean lead contaminated dust
– Roof and pipe leaks can cause increased deterioration.
– Evidence of remodeling may indicate more dust and debris
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3. Lead pipework– The presence of lead pipework for domestic water increases likelihood of lead exposure
and more severe harm outcomes.,
4. Plumbo-solvent water– Plumbo-solvent water, or water of high acidity likely to dissolve lead in pipes, affects
likelihood of exposure.
2012 3
2012 4
Lead
Average likelihood and health outcomes for all persons aged under 3 years, 1997-19991
Dwelling type and age Average
likelihood
(1 in...)
Spread of health outcomes Average
HHSRS scores
Class I Class II Class III Class IV
Non HMOs Pre 1920 39,060 0.0 1.0 9.0 90.0 0 (J)
1920-45 40,710 0.0 1.0 9.0 90.0 0 (J)
1946-79 99,580 0.0 1.0 9.0 90.0 0 (J)
Post 1979 179,600 0.0 1.0 9.0 90.0 0 (J)
HMOs Pre 1920 38,680 0.0 1.0 9.0 90.0 0 (J)
1920-45 33,730 0.0 1.0 9.0 90.0 0 (J)
1946-79 63,930 0.0 1.0 9.0 90.0 0 (J)
Post 1979 59,740 0.0 1.0 9.0 90.0 0 (J)
All Dwellings 58,400 0.0 1.0 9.0 90.0 0 (J)
Potential for Harm (UK Standards) – N/A for any U.S. urban or rural setting.
1Table from HUD Guidance Manual on HHSRS. Data should be generalizable to the United States, as “mainly US studies or high exposure area studies were used to
generalize current background rates of lead exposure for children in the UK” (p. 78).
Adjusting averages to fit local circumstances
Detroit Data:
In 2011, there were 64,302 children under the age of 6 in Detroit; 28,674 (44.6%) were tested
for lead.
2,317 (8.08%) had blood lead levels from 5 to 9 µg/dL.
310 (1.08%) had a confirmed EBLL between 10-14 µg/dL.
105 (0.37%) had a confirmed EBLL between 15-19 µg/dL.
120 (0.42%) had a confirmed EBLL between 20-44 µg/dL.
10 (0.0003%) had a confirmed EBLL ≥ 45 µg/dL.
There were another 66 children with elevated capillary tests (50 between 10-
14 µg/dL, 7 between 15-19 µg/dL, & 9 between 20-44 µg/dL) that were not
confirmed by a venous test.
• 9.95% of Detroit children have a level over 5 µg/dL,
• Based on this data, we have adjusted our Average
Detroit Likelihood to 1 in 10
7. Lead Likelihood Outcome Class I Outcome Class II Outcome Class III Notes
Detroit Local Outcomes 0 0.5 10
Average
A. With lead grant 1 in 180 or 320
B. New windows but no lead grant 1 in 32
C. Old win., little chipping paint 1 in 10 or 1 in 18
D. bad front porch, some chipping paint. 1 in 6
E. poor condition ext. paint 1 in 6 increase
moderate chipping paint and all old windows1 in 3 increase
Adjusting averages to fit local circumstances
How do we determine outcomes:
Class I: Death- very unlikely (statistically zero)
Class II: Hospitalization because of chelation
Class III: Repeated poisonings; lead level does not go down; higher blood
lead level
The highlighted portion represents the average house in Detroit. Rating
guide based on data and informed professional judgment.
What would influence likelihood and outcome?
Windows and window components…
Severe cases- Increase both likelihood and outcome
Doors, door components, and interior trim
Exterior surfaces, porches, and components
Metal Objects
What may not be a lead hazard?
Ceilings and walls
Look for “alligatoring”
As we all know, the best way to measure is
through a Lead Inspection/ Risk Assessment.
•But without this, assume lead based paint
(based on age of house and components) and
use your informed professional judgment
2012 12
Determining Your Likelihoods and Outcomes:
Hazard Prevalence in HHRS Study Sites
• Poor housing quality is a major risk factor elevated blood lead levels. Older housing (pre-1978) is more likely to have lead products, such as paint or piping.– In Detroit, 62.2% of housing was built before 1950, a substantially
higher percentage than any other county in Michigan.
– In Alameda County, CA, 29.8% of housing was built before 1950, and another 48.7% was built between 1950 and 1979.
• Chipping, peeling paint can lead to higher lead levels in the home. – According to the 2003 American Housing Survey, 72,100 (3.8%) of
units in metro Detroit (Wayne, Macomb, Oakland, St. Clair, Monroe, Livingston, & Lapeer counties) had this problem.
– In the AHS’s 1998 survey of metropolitan Oakland (Alameda & Contra Costa counties), 42,100 housing units (4.7%) had broken plaster or peeling paint in their interiors.
2012 13
Outcome Data: National
• Nationally, in 2010 there were 24,258,220 children under 6 years old – 3,937,631 of those children were tested for an elevated blood lead level (EBLL).
– Of those children that were tested, 24,043 (0.61%) had an EBLL ≥ 10 µg/dL (the previous CDC action level).
– Another 238,260 children tested (6.05%) had a blood lead level between 5-9 µg/dL, above the new CDC action level of 5 µg/dL.
2012 14
Outcome Data: Oakland (CA)
• In 2009, 17,892 children ages 0-5 were tested
for lead.
– 97 (0.5%) had an EBLL of 9.5+ µg/dL
– 524 (2.9%) had a blood lead level of 4.5 to < 9.5
µg/dL.
• Statewide, there were 2,426 cases of an EBLL 9.5+
µg/dL, meaning Alameda accounted for nearly 4%
of all such cases in California.
2012 15
16
Healthy Home Rating System Project Leadership
2012
Lyke Thompson
Director
CUS/WSU
(313) 577-5209
Allyson Lindsey
Research Assistant
CUS/WSU
(313) 577-9382
Angie Sarb
Research Assistant
CUS/WSU
(313) 577-8911
David Ormandy
Professorial Fellow
University of Warwick
+44 (0) 76524 936