Identification and Control ofLead Hazards in Housing

David Jacobs, PhD, CIHNational Center for Healthy Housing

United StatesApril 2010

Evidence of the Link Between Lead Paint and Lead Poisoning

• Historical• Case Surveillance Data• Environmental Correlate Studies• Stable Isotope Ratios

Lead-Based Paint as a Major Source of Childhood Lead Poisoning: A Review of the Evidence in Lead In Paint, Soil and Dust: Health Risks, Exposure Studies, Control Measures and Quality Assurance, Michael E. Beard and S.D. Allen Iske, Eds, American Society for Testing and Materials, Philadelphia, p. 175-187, 1995.

DUST

Lead Exposure Pathway

Steps to Eliminate Lead Paint Hazards

• Determine if hazards are present

• Determine cause of hazard (water, others)

• Protect Occupants & Workers

• Hazard Control Options

• Cleanup

• Dust Testing

RMD LPA Lead Paint X-Ray Fluorecense Analyzer

• Measures lead in as little as 2 to 4 seconds with 95% confidence

Pb

K

L

M

N

O

e-

e-

E1=Eb

Photoelectric

E1>>Eb

L-Shell XRF

K-Shell XRF Compton Scatter

XRF Generation

Control Source of Paint Failure

Options

• Permanent– Replace windows, doors, other building items

– Enclose lead paint (new walls, siding)

– Encapsulate lead paint (special long term coatings)

– Remove lead paint using wet scraping, low-temperature heat guns, chemicals

• Short Term (Management)– Paint Stabilization

– On-going Maintenance

Options (2)

• Dust Control– Friction & Impact Surfaces– Special Cleaning

• Bare Soil– Vegetation– Mulch– Removal

Avoid Tracking Lead Dust

Plastic Sheeting Exterior

Paint Scraping (Wet Methods)

Containment for High Dust Jobs

Dust and Friction/Impact

Enclosing Window SillsWith Sheet Metal

Cleanup and Dust RemovalUse High Efficiency Particulate Arrestor

(HEPA) Vacuums and Wet Methods

Wet CleaningSeparate Wash and Rinse Water

Dust (Wipe) Testing

Dust Wipe Sampling MethodHUD Guidelines

Appendix 13.1: Wipe Sampling for

Settled Lead-Contaminated Dust

US Dust Lead Standard

• Floors = 40 ug/ft2

• Interior Window Sills = 250 ug/ft2

• Set so that less than 5% of children would develop a PbB above the intervention level (15 ug/dL)

• Set in 1999• Now widely perceived as being insufficiently

protective• New NCHH proposal

– 10 ug/ft2 and 100 ug/ft2 for floors & sills

Key US Lead Exposure LimitsAmbient Air (old) 1.5 ug/m3

Ambient Air (new) 0.1 – 0.3 ug/m3

Settled Dust (Floors) 40 ug/ft2

10 ug/ft2 (NCHH proposed)

Settled Dust (Sills) 250 ug/ft2

Play Soil (bare) 400 ppm

Yard Soil (bare) 1200 ppm

Drinking Water 15 ug/L

New Housing Paint 600 ppm (90)

Existing Housing Paint 1 mg/cm2 or 5,000 ppm

Key US Lead Exposure Limits (2)

Workplace Air (8 hrs) 50 ug/m3 Permissible

30 ug/m3 Action Level

Exterior Concrete (Guidance)

800 ug/ft2

Blood (Occupational) 30 ug/dL

Blood (Advisory) 10 ug/dL (some jurisdictions now at 5)

The Power of Surveillance and National Surveys

0

5

10

15

20

25

Pre '46 '46-'73 '74 - Present

Age of Residence, year built

Po

iso

ne

d C

hild

ren

(%

)

From the Third National Health and Nutrition Examination Survey (NHANES III), Phase 2, 1991-1994

National Average for all children (4.4% with Blood Lead Levels above 10 g/dL)

African American Children

Low Income Children

All Children

Housing Surveillance Data: Where is the Remaining Lead Paint?

Dust Lead & Paint Lead:Ease of Contamination

• Current US definition of lead paint = 1 mg/cm2

• Sand a one square foot area, turn it into dust

• Spread the dust over a 10 ft x 10 ft room

• Resulting lead dust loading = 9,300 ug/ft2

• Current US Government Limit = 40 ug/ft2

Prohibited PaintRemoval Methods

• Power Sanding

• Flame Torching

• Abrasive Blasting

• Methylene Chloride Paint Strippers

Lead Paint Protectionsin the US

• Health-based exposure standards for paint, dust or soil

• Standard inspection or abatement protocols

• Prohibited paint removal methods

• Laboratory QA/QC

• Performance criteria for paint XRFs

Lead Paint Protections (cont’d)

• Trained or licensed inspectorate or abatement work force

• Occupational standards to protect workers• Training curricula• Public education• Disclosure of known lead paint hazards & no

enforcement• Funding to address hazards in low-income

privately owned high risk housing

Benefits of Window Replacement

• Lead Dust Accumulation

• Energy Savings: Heating and Cooling

• Housing Value

• Other?

HUD Pb Paint Hazard Control Evaluation Blood Lead Declined 37%

Source: NCHH, UC 2004

Figure 9-3: Geometric Mean Blood Lead Levels (μg/dL) from Pre-Intervention to Two-Years Post-Intervention by Sampling Phase and Grantee

0

5

10

15

Pre- Immediate Post- Six Months Post- One-Year Post- Two-Year Post-

Sampling Phase

Geo

met

ric

Mea

n B

lood

Lea

d L

evel

(μ

g/dL

)

ALL

Window Sill Lead Dust 12 Years After Abatement

Floor Lead Dust 12 Years After Abatement

Important Elements of US Approach

1. Research on Exposure Pathways (Lead as multi-media pollutant)

2. National and Local Surveillance on both Health and Housing Data is Essential

3. Guidelines, Legislation, Regulation & Enforcement

4. Education & Market-Based Approaches

5. Articulation of National Plan

6. Subsidy and Enforcement Targeted to Highest Risk

7. Evaluation of Exposure Control

8. High Cost of the Reactive Approach

Case Report One House in New Orleans

“Until effective standards for the domestic environment are devised, it is likely that children will continue to be employed as biological indicators

of substandard housing.”

Donald Barltrop, 1974

• Calling for a Global Ban on Lead Use in Residential Indoor and Outdoor Paints, Children’s Products, and All Nonessential Uses in Consumer Products

• Policy Date: 11/5/2007Policy Number: LB-07-01

David E. Jacobs, PhD, CIH

Director of Research

National Center for Healthy Housing

5025 Hawthorne PL NW

Washington, DC 20016

202-607-0938

www.nchh.org

dejacobs@starpower.net