lead poisoning in the 21 st century

LEAD POISONING LEAD POISONING in the 21in the 21stst Century Century

Jerome A. Paulson, MD, FAAPProfessor of Pediatrics & Environmental & Occupational

HealthGeorge Washington University

Medical Director for National & Global AffairsMid-Atlantic Center for Children’s Health & the Environment

Child Health Advocacy InstituteChildren’s National Medical Center

Mid-Atlantic Center for Children’s Health & the Environment - MACCHE

DisclosuresDisclosures

• This material was developed by the Mid-Atlantic Center for Children’s Health & the Environment and funded under the cooperative agreement award number 1U61TS000118-03 from the Agency for Toxic Substances and Disease Registry (ATSDR).

• Acknowledgement: The U.S. Environmental Protection Agency (EPA) supports the PEHSU by providing funds to ATSDR under Inter-Agency Agreement number DW-75-92301301-0. Neither EPA nor ATSDR endorse the purchase of any commercial products or services mentioned in PEHSU publications.

• Dr. Paulson has consulted with lawyers in lead poisoning cases


OBJECTIVESOBJECTIVES

• After attending this session the participant willbe able to discuss why lead poisoning is still a

problembe able to discuss the extent of lead poisoning in the

USbe able to explain the disproportionate impact of

lead poisoning on minority populationsbe able to explain the importance of primary

preventionbe able to utilize pediatric environmental health

specialty units as a clinical and educational aid.


LEAD POISONINGLEAD POISONING

Very common, very significant environmental health problem for

children


Scope of the ProblemScope of the Problem

• Have the potential to eliminate childhood lead poisoningleast 4 million households have children

living in them that are being exposed to lead

About 500,000 children with blood lead levels over 5 µg/dL

http://www.cdc.gov/nceh/lead/


Primary Prevention is the Only Primary Prevention is the Only Appropriate Approach to the Appropriate Approach to the

Resolution of the Lead Poisoning Resolution of the Lead Poisoning ProblemProblem

• Screening of children may have been appropriate in the past & must continue until…

• Making housing lead-safe is what is appropriate now and in the future


Historical PerspectiveHistorical Perspective

• Use of lead in ancient times for water pipes and utensils

• Late 19th century – recognition of problem in some parts of world

• Early 20th century - banning residential use of lead-based paint in some parts of the world

• Throughout the 20th century – obfuscation on the part of the lead industry about the hazards of lead

Lead Pipe in the Ruins of PompeiiEruption 79 CE



• 1920’s introduction of tetraethyl lead as octane booster in gasoline – subsequent obfuscation on the part of industry about the hazards of tetraethyl lead

• 1940’s recognition by Byers and Lord that lead poisoning created long-term sequela in survivors

• 1960’s introduction of chelation by Julian Chisolm as a means of preventing seizures, coma and death



• 1970’s and beyond - decrease in average blood lead level in children in the US

• 1980’s and beyond – recognition that “low lead levels” are harmful to children

• Marked decrease in average blood lead levels in kids in the US


Change in Blood Change in Blood Lead Level in US Lead Level in US

Over TimeOver Time• 1976-1980

88% of children 5 and under with BLL ≥ 10 μg/dL

Geometric mean BLL in children 5 and under = 14.9 μg/dL


Blood Lead Level for Blood Lead Level for Children Aged 1-5 Years Children Aged 1-5 Years by Year of NHANES, USby Year of NHANES, US


Centers for Disease Control. (2012). Fourth National Report on Human Exposure to Environmental Chemicals: Updated Tables September 2012. Accessed at: http://www.cdc.gov/exposurereport/

Jones, R., Homa, D., Meyer, P., Brody, D., Caldwell, K., Pirkle, J., & Brown, M. (2009). Trends in blood lead levels and blood lead testing among US children aged 1 to 5 years, 1988-2004. Pediatrics, 123(3), e376-e385. doi:10.1542/peds.2007-3608

Mahaffey KR, Annest JL, Roberts J, Murphy RS. National estimates of blood lead levels: United States, 1976-1980. N Engl J Med 1982;307:573-9.

Where Did Success In Where Did Success In Lowering Lead Levels Lowering Lead Levels

Come From?Come From?

• Gasoline• Paint• Cans• Water• Ceramics

http://www.epa.gov/bns/lead/Fig_01.gif


How Do Children How Do Children Get Lead Poisoned Get Lead Poisoned

Today?Today?• Old paint• Lead on the ground

From paintFrom past use of leaded gasolineIndustrial sources – smeltersSolder


OtherOther

• As lead paint becomes less common, “Other” becomes proportionately more important


Other Potential Other Potential Sources Of Lead In The Sources Of Lead In The

EnvironmentEnvironment• Lead glazed pottery• Brass fittings in well pumps• Lead water pipes• Home remedies or cosmetics• Firing ranges• Automotive repair• Casting ammunition, fishing weights or

sinkers• Burning lead painted wood or lead batteries


Who Are the Who Are the Children at Greatest Risk?Children at Greatest Risk?


One And 2 Year-old One And 2 Year-old ChildrenChildren

• Increased mobility during second year of life, resulting in more access to lead hazards

• Normal hand to mouth activity


Minority ChildrenMinority Children

• Traits associated with higher BLLsBlackHispanicPoverty (% on Medicaid)Increased crowdingOlder housing

Lanphear: Pediatrics, Volume 101(2).February 1998.264-271Bernard SM. McGeehin MA. Pediatrics. 112(6 Pt 1):1308-13, 2003


Impact of Lead on the Impact of Lead on the BodyBody

• Maternal lead levels may effect pregnancyPreterm laborLead in mothers body, even from her

childhood, may cross placenta and enter the baby


Impact of Lead on Impact of Lead on the Bodythe Body

• Blood lead levels in children20 μg/dL – decreased nerve conduction

velocity40 μg/dL – decreased hemoglobin

synthesis80 μg/dL – encephalopathy: seizures,

coma> 100 μg/dL – death


The Impact of Low The Impact of Low Blood Lead LevelsBlood Lead Levels

• Learning disabilities• Hyperactivity• Aggression and other behavior

problems• Decreased IQ• Decreased linear growth


Neurobehavioral Neurobehavioral Effects of “Low” Lead Effects of “Low” Lead

LevelsLevels• Lowers IQ

Individual impact small - about 4 IQ points for blood lead levels of 2.4-10 mcg/dL

Population impact very significant– Quadruple risk of IQ < 80: 16% vs. 4%– 5% of low leads with IQ > 125, O% of high

leads.


Small Individual Small Individual Effects Can Have Large Effects Can Have Large

Population EffectsPopulation Effects

Weiss B. Neurotoxicology. 1997;18:581–6.

57% increase in “Intellectually Impaired “Population


High Lifetime Mean Blood Lead (26 g/dL)

Low Lifetime Mean Blood Lead (7.6 g/dL)

activation in left frontal cortex, adjacent to Broca's area, and left middle temporal gyrus, including Wernicke's area, were found to be significantly associated with diminished activation in subjects with higher mean childhood blood lead levels, whereas the compensatory activation in the right hemisphere homolog of Wernicke's area was enhanced in subjects with higher blood lead levels. Yuan, et al. 2006

Childhood lead exposure has a significant Childhood lead exposure has a significant and persistent impact on brain and persistent impact on brain

organization associated with language organization associated with language functionfunction

What Is The Current What Is The Current Blood Lead Blood Lead

Reference Value?Reference Value?

5 µg/dL


What Is A Normal What Is A Normal Blood Lead Level?Blood Lead Level?

UNKNOWN


What Is A Safe What Is A Safe Blood Lead Level?Blood Lead Level?

UNKNOWN


Case 1Case 1

• This is a 2-year old Hispanic male who had a blood lead level of 42 mcg/dL on a routine screening test.

• What do you want to know?


Case 1Case 1

• Where does he live?• How old is the home?• Is there any lead in the water?• What other exposures could there

be?


Case 1Case 1

• Possible exposure sources in Hispanic familiescandy produced in Mexico (tamarind candy)potteryfolk remedies used in some Hispanic

households to treat "empacho," – lead oxide, a yellow-orange powder (greta),– lead tetroxide, a bright orange powder

(azarcon(also known as reuda, liga, coral, alarcon and maria luisa)


CDC. Lead Poisoning Associated with Ayurvedic Medications---Five States, 2000--2003. MMWR. July 9, 2004; 53(26):582-584.

General Principles General Principles for Disease Screeningfor Disease Screening

AAP Textbook of Pediatric Care. Chapter 36 Screening: AAP Textbook of Pediatric Care. Chapter 36 Screening: General Considerations. Paul H Dworkin, MDGeneral Considerations. Paul H Dworkin, MD

1. The condition must have significant morbidity or mortality, with serious consequences if not detected and remediated early.

2. The condition must be sufficiently prevalent to justify the cost of screening programs.

3. The screening program must include the entire population, especially those at particular risk for the condition.

4. Diagnostic tests must allow affected individuals to be distinguished from nonaffected persons or those who are borderline. Screening should be performed only for conditions that can be diagnosed with certainty


General Principles General Principles for Disease Screeningfor Disease Screening

AAP Textbook of Pediatric Care. Chapter 36 Screening: AAP Textbook of Pediatric Care. Chapter 36 Screening: General Considerations. Paul H Dworkin, MDGeneral Considerations. Paul H Dworkin, MD

5. The condition, after detection, must be treatable or controllable.6. Detection and treatment during the asymptomatic stage must improve prognosis, and early treatment must have significant advantage7. Adequate resources must be available for the definitive diagnosis and treatment of disorders identified by screening8. The cost of screening must be outweighed by the savings in suffering and alternative expenditure that would occur if the condition were not diagnosed until the symptomatic stage


Criteria 4: Do We Have Criteria 4: Do We Have an Accurate & Reliable an Accurate & Reliable

Test?Test?• Current regulations for allowable laboratory

error permitted in BLL proficiency testing programs is ±4 μg/dL

• How does one intelligently interpret today’s BLL results if they are all ±4 μg/dL?

• How does one interpret the results of a post-intervention BLL level; i.e., BLL of 4 μg/dL before intervention and now 2 μg/dL. Is the child at lower risk?

• How does one interpret the results of a post-intervention BLL level; i.e., BLL of 4 μg/dL before intervention and now 8 μg/dL. Has the child’s BLL “doubled” as a result of the home intervention?

Criteria 5: Is the Criteria 5: Is the condition treatable or condition treatable or

controllable? controllable? • There is no data to indicate that

interventions of any sort in children with the blood lead levels of today are effective in treating or controlling the condition. The damage may well have already been done and is, by all indications, irreversible.


Criteria 6: Early Criteria 6: Early detection and detection and

treatment treatment must improve outcomemust improve outcome

• The term "asymptomatic phase" does not really apply to blood lead levels that are common today

• There is no treatment that can be offered by a health professional that can demonstratively improve prognosis.


Criteria 8: Criteria 8: Cost of early treatment Cost of early treatment

must be less than latemust be less than late• Since there is no asymptomatic

phase, this criteria cannot be fulfilled.

Primary PreventionPrimary Prevention


Residential Lead-Based Residential Lead-Based Paint Hazard Reduction Paint Hazard Reduction

Act of 1992Act of 1992• Required EPA to set health-based

regulatory standards for levels of lead in paint, dust and soil

• Required EPA to identify cost-effective methods for identifying and controlling lead hazards in housing

• Required EPA to establish a new program for training and certifying lead hazard control professionals.Public Law 102-550. http://www.epa.gov/opptintr/lead/titleten.html


Residential Lead-Based Residential Lead-Based Paint Hazard Reduction Paint Hazard Reduction

Act of 1992Act of 1992• Required notification of new buyers

or renters of pre-1978 housing that lead hazards may be present.

• Expanded efforts to identify and control lead hazards in federal low-income housing through federal and local housing programs.


Eliminating Childhood Lead Eliminating Childhood Lead Poisoning: A Federal Poisoning: A Federal

Strategy Targeting Lead Strategy Targeting Lead Paint Hazards – 2000Paint Hazards – 2000

• GoalsBy 2010, eliminate lead paint hazards in

housing where children under 6 liveBy 2010 elevated blood levels in

children will be eliminated

http://www.hud.gov/offices/lead/reports/fedstrategy2000.pdf


Eliminating Childhood Lead Eliminating Childhood Lead Poisoning: A Federal Poisoning: A Federal

Strategy Targeting Lead Strategy Targeting Lead Paint Hazards – 2000Paint Hazards – 2000

• ObjectivesIncrease federal funding of HUD’s lead

hazard control program and leverage private and other non-federal funding

Increase compliance, monitoring and enforcement of lead paint regulations

Outreach and public education


Federal Agencies with Federal Agencies with Lead Poisoning Lead Poisoning

Prevention ActivitiesPrevention Activities• Department of Housing

& Urban Development• EPA• CPSC• Department of Justice• Occupational Safety &

Health Administration• Department of

Treasury• Department of Energy• Department of Defense

• Department of Health & Human Services CDC

– ATSDR CMS (HCFA) NIH

– NICHD– NIEHS

HRSA FDA

Bernard SM. Am J Public Health. 93(8):1253-60, 2003


The Home The Home EnvironmentEnvironment

• Evolution to Healthy Homes approach

• Lead remediation +WeatherizationDampness reductionMold remediationCarbon monoxide preventionRadon hazard reduction

QUESTIONS?QUESTIONS?


PEDIATRIC PEDIATRIC ENVIRONMENTAL HEALTH ENVIRONMENTAL HEALTH

SPECIALTY SPECIALTY UNITS (PEHSUs)UNITS (PEHSUs)

The Mid-Atlantic Center for Children’s Health & the Environment

PEHSUsPEHSUs

• Pediatricians with expertise in environmental health

• Occupational and environmental health specialty physicians

• Medical toxicologists, pulmonologists, etc

• National and international network of collaborators


The Pediatric The Pediatric Environmental Health Environmental Health

Specialty Unit (PEHSU) Specialty Unit (PEHSU) Program Program

is funded by:is funded by:

The Association of Occupational and Environmental Clinic is responsible for

programmatic and financial management.

&


PEHSU RegionsPEHSU Regions


PEHSUs – PEHSUs – Resource for Education Resource for Education

• For primary care providers• For occupational health providers• For public health officials• For community organization

concerned about children and the environment


PEHSUs – PEHSUs – Resource for ServicesResource for Services

• Consultation with community providers• Consultation with departments of public

health• Consultation with parents• Consultation with community

organizations, schools and others• Multidisciplinary evaluation of children

with known or suspected exposure to environmental toxicants


PEHSUsPEHSUs Evaluation and Management ofEvaluation and Management of

• Lead poisoning• Pesticide exposures• Sick building

problems• Water pollution• Air pollution• Job related

exposures in adolescents

• Volatile Organic Compounds

• Exposure to hazardous waste sites

• Environmentally related asthma

• Agricultural pollutants

• Solvents• Carbon monoxide• Arsenic• Mercury


THE MID-ATLANTIC THE MID-ATLANTIC CENTER FOR CHILDREN’S CENTER FOR CHILDREN’S

HEALTH & THE HEALTH & THE ENVIRONMENTENVIRONMENT

(MACCHE)(MACCHE)A PEDIATRIC

ENVIRONMENTAL HEALTH SPECIALTY UNIT (PEHSU)


MACCHE

• The Children’s National Medical Center Washington, DC

• The Children’s Hospital of Philadelphia


MACCHE

• DirectorJerome Paulson, MD, FAAP

• Pediatrician/ToxicologistKevin Osterhoudt, MD, MS, FAAP,

FACMT, FAACT• Coordinator

Veronica Tinney, MPH(c)


MACCHEMACCHE

• Region 3• Pennsylvania, Delaware, Maryland, Virginia,

West Virginia, & the District of Columbia

•1-866-622-2431 •202-476-4829•www.childrensnational.org/

MACCHE


QUESTIONS?QUESTIONS?

lead poisoning in the 21 st century

Documents

childrens health

lead industry

hazards of lead lead

childhood lead

extent of lead poisoning

hazards of tetraethyl

childrenmidatlantic

cemidatlantic center