Environmental Factor, May 2011, National Institute of Environmental Health Sciences
Symposium charts impact of stress on children's environmental health
By Eddy Ball
Rosalind Wright pointed to the stress domains that can imprint on long-term memory and impact maternal and child health - finances, racism and discrimination, poor housing and uncaring landlords, and community and individual violence. (Photo courtesy of Steve McCaw)
Messer said her work in downtown Durham has reinforced her conviction that many of the forces that determine birth outcome are largely beyond a mother's personal control. (Photo courtesy of Steve McCaw)
Miranda, center, makes a point about the influence of social environment, speaking from her seat in the audience beside two NIEHS program administrators - Annette Kirshner, Ph.D., sitting to Miranda's left, and Kimberly Gray, Ph.D., far right. (Photo courtesy of Steve McCaw)
Robert Wright, seated with his wife and colleague Rosalind Wright, commented on parallels between Bilbo's work and his own. Both have found epigenetic alterations as a result of stress and environmental exposures. (Photo courtesy of Steve McCaw)
NIEHS grantees joined colleagues in the field of children's health March 25 at Duke University to explore "The Social Context of Environmental Exposures in Children." The meeting brought together leading investigators funded by NIEHS, the U.S. Environmental Protection Agency (EPA), and other sources to share their findings and learn more about EPA's environmental justice initiative and the trans-NIH National Children's Study (see text box).
The event was the annual Duke University Integrated Toxicology and Environmental Health Program (ITEHP)(http://toxicology.geneimprint.com/about/) Spring Symposium, co-sponsored by the Duke University Superfund Research Center, funded by NIEHS, and the EPA-funded Southern Center on Environmentally Driven Disparities in Birth Outcomes (SCEDDBO). The symposium was organized by Duke University Professor Marie Lynn Miranda, Ph.D.,(http://fds.duke.edu/db/Nicholas/esp/faculty/mmiranda) director of the university's Children's Environmental Health Initiative, part of the national network of Children's Environmental Health Centers, which oversees SCEDDBO, and co-facilitated by Duke University Professor Edward Levin, Ph.D., director of the ITEHP Lecture Series.
An integrated approach to children's health
In her opening remarks, Miranda introduced an integrative paradigm that re-emerged many times during the day's presentations. "Children and pregnant mothers are sitting in the middle of a triangle, including things like host factors, ... social factors, ... and, of course, environmental factors," she told the audience.
As this paradigm strives to unite various approaches for studying children's health across disciplines, it also tries to tease out temporal connections between birth outcomes and exposures and experiences that may have taken place earlier in the mother's life, but nevertheless have a bearing on the baby's health. According to Miranda and several of the other presenters, environmental justice issues, health disparities, and the built environment - what several called the "toxic soup" - can play important roles in creating social stress that helps shape maternal health and a mother's relationship with her newborn child - and, consequentially, the child's own physical and emotional wellbeing at birth and throughout life.
The importance of the affective domain
The first keynote presentation of NIEHS-supported research by Harvard University Professor Rosalind Wright, M.D.(http://www.channing.harvard.edu/wright.htm) , "Urban Asthma Paradigm: From Fragile Families to Constricting Communities," explored the immunomodulatory effects of stress, linking stress and the development of asthma. In several major studies, Wright has explored the association of biological markers of stress, allergy, and what she called "inflammation stress domains."
Following Wright was Duke Professor Lynne Messer, Ph.D.(https://fds.duke.edu/db/Provost/dghi/faculty/lynne.messer/cv.html) , who described her team's work on the Community Assessment Project (CAP) now underway in Durham, N.C. Messer argued, "Places matter to residents' health," and wellbeing for mother and newborn "is not just an individual-level problem." Social stressors, such as dilapidated housing and crime, correlate strongly with such negative health outcomes as low birth weight and preterm birth.
Integrating human and animal studies into the paradigm
Miranda returned to the podium to fill in for an ailing colleague with a review of SCEDDBO's investigations, "Air Quality Across Social and Spatial Lines." Along with geocoding birth outcomes and air quality, the SCEDDBO team of investigators has conducted clinical and animal studies of combined exposures to diesel exhaust and ozone and the influence of psychosocial stress on birth outcomes. In the mouse model experiments led by Professor Richard Auten, M.D.(http://www.dukehealth.org/physicians/richard_l_auten) , investigators have experimented with deprived, standard, and enriched housing as variables correlated with health endpoints.
Duke Professor Staci Bilbo, Ph.D.(http://www.dibs.duke.edu/research/profiles/47-staci-bilbo) , presented NIEHS-supported research on the fetal origins of cytokine expression in the immune response. Early-life infection, immune upregulation, maternal stress, and trauma, Bilbo argued, can prime microglia, the resident immune cells of the brain, so that they over-respond to a second hit, with enduring consequences on a child's health.
The final speaker, NIEHS grantee and Harvard Associate Professor Robert Wright, M.D.(http://www.hsph.harvard.edu/faculty/robert-wright/) , explored the synergistic effects of social stress and lead exposure on the process of brain development through synaptic plasticity modeling and pruning. Although he reported on the devastating effects of lead exposure and stress on synaptic architecture, Wright ended on a more hopeful note, as he discussed human and animal experiments that suggest enrichment interventions, given time, might have the potential to reverse many of the cognitive and behavioral deficits exhibited by lead-exposed children.
Federal initiatives in children's environmental health
The symposium's middle session moved from reports on research to a look ahead with discussion about EPA's EJ [Environmental Justice] 2014 (http://www.epa.gov/compliance/ej/plan-ej/index.html) initiative and progress in the National Children's Study.
Onyemaechi Nweke, Dr.PH., of the EPA Office of Environmental Justice, offered workshop attendees a backstage look at her agency's efforts to integrate EJ considerations into rule making, such as the National Ambient Air Quality Standards, to reduce disproportionate burden on communities of color and lower socioeconomic status.
While Nweke acknowledged the complex and time-consuming rulemaking process followed by EPA in setting industry-specific and performance standards, she pointed to the commitment of EPA Administrator Lisa Jackson to requiring an explicit consideration of EJ throughout the rulemaking process and asking the important question about environmental exposures - "Are there racial or economic inequalities involved?"
An audience that was interested for obvious reasons also heard a presentation on the National Children's Study (NCS)(http://www.nationalchildrensstudy.gov/Pages/default.aspx) by Maria Lopez-Class, Ph.D., NCS Study Center Contracting Officer Technical Representative at the Eunice Shriver National Institute of Child Health and Human Development. Lopez-Class described the formative work now underway in the 31 NCS Vanguard Studies and plans for NCS sub-studies at various sites across the nation.
Along with her progress report on NCS, which is poised to launch fully in 2012, attendees listened to some welcoming news about plans to measure biological markers and self-reports of maternal stress as part of the 21-year study of child health. Such nationwide data collection could help a number of the workshop participants expand their own research into the myriad contributions to maternal stress and suboptimal birth outcomes.