Understanding Risk Gradients from Environment on Native American Child Health Trajectories: Toxicants, Immunomodulation, Metabolic Syndromes, & Metals Exposure

The backstory: This study evolves from a congressional mandate to study non-occupational exposures to uranium wastes among residents of the Navajo Nation and concerns raised by community members, especially women, about the effects of such exposures on pregnancies and birth outcomes. Part of the basis for this directive was testimony given at a hearing of the U.S. House Committee on Oversight and Government Reform on October 23, 2007 and in subsequent meetings of the the Committee staff and representatives of federal agencies and the Navajo Nation. The Committee learned that the Navajo Nation was heavily mined of uranium to support development of the atomic bomb and subsequent cold-war weapons production from 1942 through the late-1960s. The last mines on or next to the Navajo Nation closed in the mid-1980s, leaving  1,100 mine waste sites associated with 520 discrete mines, most of which have never been fully remediated. In spite of the potential for long-term, low-level chronic exposures to community members, no comprehensive health studies have been conducted to assess the impact to the Navajo people from exposure to these wastes. The committee directed five federal agencies to come up with a plan to remediate abandoned uranium mines (AUMs), remediate or replace homes made with mine wastes, locate and replace water sources contaminated with uranium and other hazardous substances, and support or conduct health studies in uranium-impacted communities. Congress subsequently appropriated funds for the studies referenced in the 2009 budget, and in Fall 2009, ATSDR staff held meetings with community members, Navajo Nation agencies, Navajo Area Indian Health Services (NAIHS) staff and academic institutions doing environmental health research on the Navajo Nation to determine how to best meet the congressional mandate. ATSDR determined that investigating the possible effects of environmental exposures to uranium wastes on Navajo pregnancies and birth outcomes would appropriately respond to both the community concerns and to the congressional mandate. The University of New Mexico (PI: Dr. Johnnye Lewis)  research team developed an initial research protocol. In 2010, the Centers for Disease Control (CDC) awarded a cooperative agreement to UNM to work with CDC/ATSDR, NAIHS, and the Navajo Nation to examine the impact of uranium exposures on birth outcomes and early child development on Navajo Nation.

Use a prospective birth cohort design to examine contribution of uranium exposures on increased congenital malformations and developmental delays in offspring of exposed parents.
Aim 1: Cooperatively design and conduct a prospective epidemiologic birth cohort study of pregnancy outcomes and child development in relation to uranium waste exposures among Navajo mother-infant pairs
Aim 2: Characterize the cohort with respect to mobility, exposures, co-exposures, demographic and cultural characteristics that may influence outcomes
Aim 3: With guidance from the expanded Community Liaison Group (CLG) and collaboration with community health workers, provide extensive outreach on the study goals and results, on prenatal care, available clinical services, and mitigation of any exposure-induced health effects on the Navajo
Aim 4: Work with Navajo agency partners to develop their environmental health capacity and to develop a sustainability plan for continued follow-up of the cohort

The project today:

Aim 1: Identify associations between prenatal and postnatal exposure to metal mixtures measured by biomonitoring and other available exposure parameters and comprehensive developmental assessment at 4 years of age in study participants from Navajo, Cheyenne River and Oglala Sioux Tribes.
Aim 2: Identify associations between prenatal metals exposures and specific reactivity of maternal autoantibodies (sAuAb) or the presence of fetal-brain reactive antibodies (ABA) with developmental trajectories assessed in Aim 1.
Aim 3: Identify associations between prenatal and postnatal metal exposures with specific alterations in maternal and/or offspring cytokine and lymphocyte profiles with developmental trajectories assessed in Aim 1.
Specific Aim 2: Identify associations between prenatal and postnatal metal exposures determined by biomonitoring and other expsoure parameters and imune dysregulation with development of childhood obesity through yearly anthropometric measurements through age 5 in study participants from Navajo, Cheyenne River and Oglala Pine Ridge Sioux Tribes.