Abstract
Background
Flint, Michigan had elevated water lead (Pb) levels during the 2014–15 Flint Water Crisis (FWC) and reports claim the exposures caused excess fetal deaths.
Objective
To model the likelihood of excess fetal deaths occurring from FWC lead exposure and compare results to Vital Records.
Methods
We used an established bio-kinetic model to predict relative blood lead trends in pregnant women from characteristic exposure to 90th percentile water lead levels (WLLs), and another established model to then estimate characteristic miscarriage (<20 gestation weeks) odds ratios (OR) in Flint (2011–17). For comparison, we made similar predictions for exposures during (1) Washington DC’s worst water lead crisis year (2001), (2) Flint “Resident Zero” home with anomalously high WLLs, and (3) 19th century lead-based abortifacients. Data on stillbirths (≥20 gestation weeks) and total fertility rates were obtained from the State of Michigan.
Results
The models predicted that pregnant women drinking water with representative 90th percentile WLLs had a miscarriage OR during the worst FWC period (June–August 2014) of 1.21 (95% CI = 1.02,1.60), versus 1.66 (95% CI = 1.07, 3.56) during a time of high water lead 3 years before the FWC and 1.00 (95% CI = 1.00, 1.01) post-FWC. The corresponding predicted OR in late-2001 for Washington D.C. when higher fetal death rates were statistically associated with very high WLLs was 3.01 (95% CI = 1.16, 16.23). No apparent differences were revealed in overall and race-specific stillbirth rates before, during, or after the FWC. Total fertility rates dropped 6.8% during the FWC (April 2014–October 2015 versus April 2012–October 2013), but this is now revealed to be within the normal annual variation (−9.4% to +15%) observed post-FWC when residents were protected from water lead exposure.
Significance
Neither model simulations nor Vital Records data are consistent with the hypothesis that there was an uptick in fetal deaths or decreased fertility attributable to water lead exposure during the FWC.
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Acknowledgements
We are grateful to Dr. Gary Diamond (Syracuse Research Corporation) for providing a user-friendly Excel version of the ICRP bio-kinetic model (v. R5CHELATE.3000), Drs. Sarah Lyon-Callo and Patricia McKane (Michigan Department of Health and Human Services) for stillbirth data and providing feedback on this manuscript under a Data User Agreement, Drs. David J. G. Slusky (University of Kansas) and Daniel S. Grossman (West Virginia University) for general fertility rate data and relevant discussions at the 2019 American College of Toxicology conference, and Virginia Tech’s Statistical Applications and Innovations Group for statistical advice on using the miscarriage model. We also acknowledge CrowdTangle, a public insights tool owned and operated by Facebook, which allowed us to search for news shares about fetal deaths in Flint on public Facebook pages and groups.
Funding
This study was partly funded and developed under grants awarded by the U.S. Environmental Protection Agency (No. 8399375 “Untapping the Crowd: Consumer Detection and Control of Lead in Drinking Water”) and Spring Point Partners LLC to Virginia Tech. This work has not been formally reviewed by USEPA or Spring Point Partners LLC. The findings, conclusions, and opinions in this report are those of the author(s) and do not necessarily represent the official position of the USEPA or Spring Point Partners LLC. USEPA or Spring Point Partners LLC do not endorse any products or commercial services mentioned in this publication. The funding sources had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
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SR and MAE conceptualized and designed the study. MAE obtained the funding. SR conducted simulations. SR and MAE performed data analyses, interpreted results, and wrote the manuscript.
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MAE and SR worked with Flint residents to expose the Flint Water Crisis, and their data, testimony and emails have been subpoenaed in several lawsuits. They are not party to any of these lawsuits. MAE has been subpoenaed as a fact witness in many of the lawsuits, but he has refused all financial compensation for time spent on those activities. Previously, MAE served as an uncompensated fact witness in lawsuits pertaining to the Washington DC lead in drinking water crisis, all of which have ended.
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Roy, S., Edwards, M.A. Are there excess fetal deaths attributable to waterborne lead exposure during the Flint Water Crisis? Evidence from bio-kinetic model predictions and Vital Records. J Expo Sci Environ Epidemiol 32, 17–26 (2022). https://doi.org/10.1038/s41370-021-00363-z
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DOI: https://doi.org/10.1038/s41370-021-00363-z
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