LOW BIRTH WEIGHT COLLABORATION C. David Adair, M.D. Associate Professor Department of Obstetric and Gynecology The University of Tennessee College of Medicine, The Chattanooga & Knoxville Units Sean Richards, Ph.D. UC Foundation Associate Professor Environmental Department of Biological and Environmental Science The University of Tennessee at Chattanooga
OVERVIEW • Hamilton County – Leading Low Birth Weight in State and one of the top in Nation • Southeastern Council 2003 • Zip Code Analysis • ROC, Health Department • Inconclusive explanations
OVERVIEW • Historic Industry • metal foundries, coke furnaces, chemical, wood preserving, tanning and textile plants • 42 hazardous waste sites • PAHs, metals and metalloids, and chlorinated solvents • Hamilton County rests in a basin
OVERVIEW • Current Collaborative • Partners UT, ROC, Health Department, BCBS, MOD, Columbia University, University of Rochester, Southern Illinois University • Placental Morphology and toxicant concentrations
TEAM APPROACH • Epidemiologists • Toxicologists • Environmental Scientists • Research Nurses • Placental Pathologists • Analytical Chemists
OBJECTIVES • Get Background Data • Build Database/Tissue base • Establish Track Record • Enable a quick start once funding arrives
Black HC Black US White HC White US
Highest Concentration of Toxic Emissions HAMILTON COUNTY: LOW BIRTH WEIGHTS 1998-2001 N Low Birth Weight % (by Zipcode) No live birth 0-5.9% = National Average 6-8.9% Above National Average 9-11.9% 12-14.9% 15-17.9% 18-20.9% Prevailing wind Figure 1. A representation of Hamilton County’s prevalence of low birth weight infants. The population is sorted according to zipcode. Only one zipcode population (37350, yellow color) ranks within the US national average for percent of infants born with low birth weight. All other populations in Hamilton County have a greater percentage of infants born with a low birth weight than the national average. Values range from 0-20.9%. The red circle indicates an area of highest concentrated toxic emissions.
Investigative Approach • Collect placentae • Criteria for selection: • Singleton pregnancy • No multiple birth, still birth, chromosomal or major congenital anomaly • Compared parameters • Digitally analyzed placenta morphology • Analyzed for total arsenic (AA w/ graphite furnace)
Parameters: 1) Chorionic surface vascular area/perimeter 2) Chorionic disk area/perimeter vs Greater ratio 3) Distance b/w inner and outer centroids 4) Distance b/w cord insertion and disk centroid
5) Regression analysis (p<0.05) of O/E Placental weight ratio Results: Parameters that are significantly associated with reduced placental weight: Reduced area:perimeter Greater distance between centroids
Hamilton County Average = 39 ppb 35% of pop is above the Avg. Argentina Average = 34 ppb 41% of HC is above Argentina Avg. Bulgaria Average = 23 ppb 61% of HC is above Bulgaria Avg Arsenic Concentrations in Hamilton County Placentas 99.999 99.995 99.99 99.95 99.9 99.8 99 98 Centile 95 90 80 70 60 50 40 30 20 10 100 1000 10000 Arsenic Concentrations (log ppb)
Conclusions and Future Directions • Hamilton County has relatively high Arsenic concentrations • Arsenic may be a contributor to HC LBW • Many confounders • Morphology is related to placental weight • Arsenic Source? • Other metals? PFAAs?
Wins & Losses • Over 1,000 placentae • Three Federal Submissions • Three Appropriations – 2 of 3 • KOKO ROC/UTC
Acknowledgements Carrie Salafia, M.D. Columbia University Z.Q. Lin, Ph.D. University of Southern Illinois Edwardsville Kevin Johnson, Ph.D. University of Southern Illinois Edwardsville Richard Miller, Ph.D. University of Rochester College of Medicine Dawn Misra, Ph.D. University of Michigan Low Birth Weight Task Force UTC ROC Barbara Laymon Lorrie Mason Cabana Kids