Impact of Early-life Exposure to Semi-Volatile Organic Compounds (SVOCs) on Neonatal and Early Childhood Immune Function

Project Summary The immune system plays a critical role in maintaining a child’s health, and immune deficits may have serious consequences ranging from increased susceptibility to infections to allergic and autoimmune conditions. Although many factors contribute to overall immune health, emerging data suggest that early life environmental exposures interfere with immune

development and function. Identifying modifiable environmental factors that affect children’s immunity, our overarching goal is critical to reducing infant morbidity and mortality and has long- term implications for improving health. Semi-volatile organic compounds (SVOCs), including organophosphate esters,

phthalates, pesticides, and flame retardants, are used in consumer and personal care products, electronics, furniture, and building materials. As a result of their extensive use and environmental persistence, SVOCs are detected with high frequency in indoor environments, and human exposure to mixtures of SVOCs is widespread. Our proposed research assesses exposure to

SVOC mixtures throughout pregnancy and in infancy. We will investigate individual characteristics associated with higher levels of exposure and evaluate the potential for adverse health outcomes among exposed women and their children. Animal studies provide compelling evidence that exposure to individual SVOCs impacts

immune function; however, the extent to which these studies extend to human populations is unclear, particularly because they largely consider exposure to single chemicals, which does not reflect real-world exposures (i.e., those occurring in mixtures). Our primary objective is to investigate the impacts of early life exposure to SVOC mixtures on children’s immune function,

and in doing so, to fill a critical gap in the understanding of the impacts of SVOCs. This study will be the first to evaluate the role of SVOC in altering the protection of the neonate by evaluating the two most critical aspects of early life immune function: 1) passive transfer of immunity and 2) the capacity to respond to a novel pathogen-associated antigen. We will capitalize on the

infrastructure of HOPE 1000, an ongoing cohort study with longitudinal collection of SVOC exposure monitors during each trimester of pregnancy and in early childhood, and the biospecimen needed to evaluate immune function and pathogen immunity. Identifying specific SVOCs or mixtures of SVOCs that affect immunity may provide new

opportunities for interventions at the individual and policy levels. Such data are critically needed as the use of some SVOCs is predicted to increase in the coming years.