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LEAD POISONING in the 21 st Century. Jerome A. Paulson, MD, FAAP Professor of Pediatrics & Environmental & Occupational Health George Washington University Medical Director for National & Global Affairs Mid-Atlantic Center for Children’s Health & the Environment
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LEAD POISONING in the 21st Century Jerome A. Paulson, MD, FAAP Professor of Pediatrics & Environmental & Occupational Health George Washington University Medical Director for National & Global Affairs Mid-Atlantic Center for Children’s Health & the Environment Child Health Advocacy Institute Children’s National Medical Center Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Disclosures • 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 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
OBJECTIVES • After attending this session the participant will • be able to discuss why lead poisoning is still a problem • be able to discuss the extent of lead poisoning in the US • be able to explain the disproportionate impact of lead poisoning on minority populations • be able to explain the importance of primary prevention • be able to utilize pediatric environmental health specialty units as a clinical and educational aid. Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
LEAD POISONING Very common, very significant environmental health problem for children Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Scope of the Problem • Have the potential to eliminate childhood lead poisoning • least 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/ Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Primary Prevention is the Only Appropriate Approach to the Resolution of the Lead Poisoning Problem • 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 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Historical 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 Pompeii Eruption 79 CE Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Historical Perspective • 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 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Historical Perspective • 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 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Change in Blood Lead Level in US Over 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 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Blood Lead Level for Children Aged 1-5 Years by 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. Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Where Did Success In Lowering Lead Levels Come From? • Gasoline • Paint • Cans • Water • Ceramics http://www.epa.gov/bns/lead/Fig_01.gif Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
How Do Children Get Lead Poisoned Today? • Old paint • Lead on the ground • From paint • From past use of leaded gasoline • Industrial sources – smelters • Solder Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Other • As lead paint becomes less common, “Other” becomes proportionately more important Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Other Potential Sources Of Lead In The Environment • 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 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Who Are the Children at Greatest Risk? Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
One And 2 Year-old Children • Increased mobility during second year of life, resulting in more access to lead hazards • Normal hand to mouth activity Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Minority Children • Traits associated with higher BLLs • Black • Hispanic • Poverty (% on Medicaid) • Increased crowding • Older housing Lanphear: Pediatrics, Volume 101(2).February 1998.264-271 Bernard SM. McGeehin MA. Pediatrics. 112(6 Pt 1):1308-13, 2003 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Impact of Lead on the Body • Maternal lead levels may effect pregnancy • Preterm labor • Lead in mothers body, even from her childhood, may cross placenta and enter the baby Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Impact of Lead on the Body • Blood lead levels in children • 20 μg/dL – decreased nerve conduction velocity • 40 μg/dL – decreased hemoglobin synthesis • 80 μg/dL – encephalopathy: seizures, coma • > 100 μg/dL – death Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
The Impact of Low Blood Lead Levels • Learning disabilities • Hyperactivity • Aggression and other behavior problems • Decreased IQ • Decreased linear growth Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Neurobehavioral Effects of “Low” Lead Levels • 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. Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Small Individual Effects Can Have Large Population Effects 57% increase in “Intellectually Impaired “Population Weiss B. Neurotoxicology. 1997;18:581–6. Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Childhood lead exposure has a significant and persistent impact on brain organization associated with language function 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
What Is The Current Blood Lead Reference Value? 5 µg/dL Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
What Is A Normal Blood Lead Level? UNKNOWN Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
What Is A Safe Blood Lead Level? UNKNOWN Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Case 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? Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Case 1 • Where does he live? • How old is the home? • Is there any lead in the water? • What other exposures could there be? Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Case 1 • Possible exposure sources in Hispanic families • candy produced in Mexico (tamarind candy) • pottery • folk 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. Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
General Principles for Disease ScreeningAAP Textbook of Pediatric Care. Chapter 36 Screening: General Considerations. Paul H Dworkin, MD • The condition must have significant morbidity or mortality, with serious consequences if not detected and remediated early. • The condition must be sufficiently prevalent to justify the cost of screening programs. • The screening program must include the entire population, especially those at particular risk for the condition. • 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 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
General Principles for Disease ScreeningAAP Textbook of Pediatric Care. Chapter 36 Screening: General 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 advantage 7. Adequate resources must be available for the definitive diagnosis and treatment of disorders identified by screening 8. 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 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Criteria 4: Do We Have an Accurate & Reliable 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 condition treatable or 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. Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Criteria 6: Early detection and treatment must 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. Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Criteria 8: Cost of early treatment must be less than late • Since there is no asymptomatic phase, this criteria cannot be fulfilled.
Primary Prevention Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Residential Lead-Based Paint Hazard Reduction Act 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 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Residential Lead-Based Paint Hazard Reduction Act 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. Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Eliminating Childhood Lead Poisoning: A Federal Strategy Targeting Lead Paint Hazards – 2000 • Goals • By 2010, eliminate lead paint hazards in housing where children under 6 live • By 2010 elevated blood levels in children will be eliminated http://www.hud.gov/offices/lead/reports/fedstrategy2000.pdf Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
Eliminating Childhood Lead Poisoning: A Federal Strategy Targeting Lead Paint Hazards – 2000 • Objectives • Increase 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 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
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 Federal Agencies with Lead Poisoning Prevention Activities Bernard SM. Am J Public Health. 93(8):1253-60, 2003 Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
The Home Environment • Evolution to Healthy Homes approach • Lead remediation + • Weatherization • Dampness reduction • Mold remediation • Carbon monoxide prevention • Radon hazard reduction
QUESTIONS? Mid-Atlantic Center for Children’s Health & the Environment - MACCHE
PEDIATRIC ENVIRONMENTAL HEALTH SPECIALTY UNITS (PEHSUs) The Mid-Atlantic Center for Children’s Health & the Environment
PEHSUs • Pediatricians with expertise in environmental health • Occupational and environmental health specialty physicians • Medical toxicologists, pulmonologists, etc • National and international network of collaborators The Mid-Atlantic Center for Children’s Health & the Environment
The Pediatric Environmental Health Specialty Unit (PEHSU) Program is funded by: & The Association of Occupational and Environmental Clinic is responsible for programmatic and financial management. The Mid-Atlantic Center for Children’s Health & the Environment
PEHSU Regions The Mid-Atlantic Center for Children’s Health & the Environment
PEHSUs – Resource for Education • For primary care providers • For occupational health providers • For public health officials • For community organization concerned about children and the environment The Mid-Atlantic Center for Children’s Health & the Environment
PEHSUs – Resource 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 The Mid-Atlantic Center for Children’s Health & the Environment