Longitudinal Research

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The Issue | Science Objectives | Research Highlights | Impact and Outcome

The Issue

Research to identify environmental factors that contribute to childhood asthma, neurobehavioral development, and other health issues with children has been conducted on many fronts. Scientists have many research approaches, from laboratory experiments to unlock clues to the effects on health to epidemiology studies that provide real-world information on how a group of participants is affected by pollution.

Another important approach used by scientists is the longitudinal study, which involves studying how individuals may be affected by pollutants over a long period of time, sometimes decades. Observations of study subjects over long periods provides critical information about the relationship between early developmental exposures to environmental chemicals and adverse health effects.

Core or basic research is needed, however, to develop the sophisticated methods and models for designing and conducting these longitudinal studies. EPA is producing the tools needed for longitudinal studies, including one of the largest planned studies of its kind, the proposed National Children's Study. As a co-sponsor of this national study, EPA's researchers are working to provide the scientific foundation for conducting a study that will follow approximately 100,000 children (and their families) from before conception to age 21.

Science Objectives

The objectives of the longitudinal research at EPA are three fold:

determine if repeated, low-level exposure to nonpersistent pesticides, including carbamates, organophosphates, and pyrethroids, in utero or postnatally increases risk of poor performance on neurobehavioral cognitive examinations during infancy and later in childhood among those with genetic polymorphisms;
assess whether exposure to bioaerosols, including allergens, endotoxins, and mold is associated with increased risk of onset of asthma; and
elucidate the biological basis for critical periods of development as it relates to neuroendocrine disruption.

Research Goals:

Support the research needs of the proposed National Children's Study, collaborating with other partners
Identify factors that are harmful, harmless, and helpful so that prevention and intervention efforts can be targeted appropriately
Provide to the scientific and risk assessment community a dataset that can be used to address questions on children's health and development
Provide longitudinal data with measures of exposures and exposure factors for women of child-bearing age, pregnant women, and infants and toddlers
Provide an opportunity to assess the relationship between community level ambient exposure measures and individual household measures on a national scale
Provide linkage to corresponding international efforts developed with the World Health Organization, including developing a set of common core measures to help study rare outcomes such as childhood cancer
Provide unique approach data on antecedents of widely occurring childhood diseases, such as asthma
Provide access to biologic and environmental samples for intramural research collaboration
Develop novel methods of exposure or health assessment at different stages of child development

Research Highlights

An EPA-led pilot study, Babies and Environments First in North Carolina (BEFirstNC), is being planned to screen approximately 10,000 households in North Carolina to test data collection methods and recruitment and retention strategies and to evaluate the impact of common environmental factors on variations in child growth and development. The scientific data collected will be useful for longitudinal studies such as the National Children's Study. Women who reside in defined geographic areas will be enrolled prior to pregnancy or anytime during their pregnancies, and their children will be followed with repeated visits up to 18 months of age. A variety of environmental stressors and conditions will be assessed, including exposures to chemicals on the job and at home, home environmental conditions, stress, and access to medical care. Biologic and environmental samples will be collected at each study visit.
The Science to Achieve Results (STAR) grants program is supporting university-based studies that aim to develop early biological indicators of environmentally induced disease in young children. The investigators will use a suite of biological makers of exposure, effect, and susceptibility, along with environmental and questionnaire data to determine which set or combination of indicators provides predictive evidence of high risk for or onset of disease. Potential adverse health outcomes include asthma, neurodevelopmental delay, skin lesions, and cancer. This research ultimately may provide an important new tool for pediatricians, epidemiologists and health scientists to discover or even prevent disease onset in preschool-aged children.

Impact and Outcomes