IRS insecticides for malaria control and child neurodevelopment in South Africa

Summary

Principal Investigator: Brenda Eskenazi
Abstract: DESCRIPTION (provided by applicant): Every year, 250 million people are infected with malaria, resulting in 880,000 deaths, primarily to African children under age five. Many malaria-endemic countries use Indoor Residual Spraying (IRS), the application of dichlorodiphenyl trichloroethane (DDT) or pyrethroid insecticides to interior walls of homes, to control malaria. Concerns regarding the unintended consequences of chronic, high-level DDT exposure have resulted in considerable international debate. For example, the Stockholm Convention on Persistent Organic Pollutants aims to ban DDT, while the World Health Organization and the U.S. Agency for International Development promote and/or fund IRS, including with DDT. DDT and pyrethroids are neurotoxicants in insects and animals. Human studies, primarily conducted in Western populations with low to moderate levels of exposure, suggest that prenatal exposure to DDT and its breakdown product, DDE, may adversely affect children's neurodevelopment. DDT/E exposure has also been related to adverse effects on thyroid function, gestational duration and birth weight, and changes in global DNA methylation, which could serve as pathways for compromised neurodevelopment. Although there is virtually no research in humans on the health effects of pyrethroids, research in rodents has shown detrimental effects on neurodevelopment both independently and synergistically with DDT. No study has evaluated the impact of human exposure to DDT and/or pyrethroids on neurodevelopment in the context of IRS We propose to address these important knowledge gaps by examining relationships between exposure to IRS insecticides and neurodevelopment, and possible mediators in a birth cohort study. We aim to enroll 750 rural South African mothers and to follow their children for 24 months, assessing exposures and neurodevelopment prospectively. We take advantage of a natural experiment where gradations in altitude impact mosquito survival and, by extension, use of IRS, but sprayed and unsprayed villages are otherwise similar, e.g, demographically. Our proposed study will be the first to: 1) assess levels and determinants of IRS insecticide exposure to pregnant women and infants in IRS-treated homes;2) study the effects of very high DDT/E and pyrethroid exposures on human neurodevelopment;3) assess the relative and synergistic health impacts of alternative IRS insecticides;and 4) evaluate whether poverty, malnutrition and poor health potentiate the health effects of these exposures. We will introduce two techniques with wider implications for environmental health science: the use of PBPK models to quantify the relative contributions of in utero, breast milk, and other postnatal environmental exposures in infants, and the use of state-of-the-art epigenetic methods to determine whether environmental exposures can alter DNA methylation in fetal tissue. This study aims to provide data to evaluate the risk/benefit of different methods of malaria control and for the development of appropriate interventions to reduce exposure to pregnant women and children.
Funding Period: 2011-08-25 - 2016-03-31
more information: NIH RePORT

Top Publications

  1. ncbi mSpray: a mobile phone technology to improve malaria control efforts and monitor human exposure to malaria control pesticides in Limpopo, South Africa
    Brenda Eskenazi
    Center for Environmental Research and Children s Health CERCH, School of Public Health, University of California, 1995 University Ave, Suite 265, Berkeley, CA 94704, USA Electronic address
    Environ Int 68:219-26. 2014

Detail Information

Publications1

  1. ncbi mSpray: a mobile phone technology to improve malaria control efforts and monitor human exposure to malaria control pesticides in Limpopo, South Africa
    Brenda Eskenazi
    Center for Environmental Research and Children s Health CERCH, School of Public Health, University of California, 1995 University Ave, Suite 265, Berkeley, CA 94704, USA Electronic address
    Environ Int 68:219-26. 2014
    ....

Research Grants30

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    Lee S Newman; Fiscal Year: 2013
    ..The productivity and continuance demonstrate quality, commitment and ability to work together. PROGRAM AS INTERGRATED EFFORT ..
  2. Semi-volatile PCBs: Sources, Exposures, Toxicities
    Larry W Robertson; Fiscal Year: 2013
    ..These data and dietary studies in the last Aim will provide a scientific basis for risk assessment and advice for stakeholders with the ultimate goal to protect highly-exposed individuals and populations. ..
  3. DDT &PBDE exposure, puberty onset and neurodevelopment in Mexican-American girls
    Brenda Eskenazi; Fiscal Year: 2013
    ..abstract_text> ..
  4. Puerto Rico Testsite for Exploring Contamination Threats (PRoTECT)
    Akram N Alshawabkeh; Fiscal Year: 2013
    ..The cross-disciplinary approach will employ the data-rich centralized data repository and integrated modeling/analysis capabilities to better understand complex interrelationships between multiple risk factors. ..
  5. Elucidating Risks: From Exposure and Mechanism to Outcome
    James A Swenberg; Fiscal Year: 2013
    ..This Program is highly relevant to Superfund by addressing high-priority chemicals and by focusing on mechanisms underlying health effects, exposure assessment, and remediation to mitigate exposure and toxicity. ..
  6. Longitudinal study of exposure to PBDEs and PFCs and child neurobehavior
    Kimberly Yolton; Fiscal Year: 2013
    ..This research is closely related to the NIH mission to investigate prevalent environmental toxicants and children's neurodevelopment. ..
  7. Impact of TB on Outcome of HIV in Pregnant Women
    Richard E Chaisson; Fiscal Year: 2013
    ....
  8. The effect of peptide therapy and allergen provocation on Fel d1-specific T Cells
    Mark Larché; Fiscal Year: 2013
    ..Additionally this Aim will assess the effects of peptide immunotherapy in the murine allergen challenge model ..
  9. Superfund Metal Mixtures, Biomarkers and Neurodevelopment
    David C Bellinger; Fiscal Year: 2013
    ..Aim 4- To promote rapid dissemination of significant research findings;and Aim 5- Compliance- To ensure compliance with NIH requirements for data and resource-sharing and the human and animal institutional review board requirements ..
  10. Stanford University Center for Reproductive and Stem Cell biology
    Margaret T Fuller; Fiscal Year: 2013
    ..abstract_text> ..