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The Sum of the Parts: Developing a Systems-Level Approach to Protect Children's Health

Published October 22, 2018  

Children laugh outsideDespite major advancements and lasting impacts in advancing children’s environmental health over the past 20+ years, significant challenges remain. Keeping the rate of progress ahead of the pace of emerging challenges requires new, more interdisciplinary research efforts and novel ways to holistically consider the many complex interactions linking the environment to children’s health and well-being. 

One promising research avenue is the total environment approach. This approach recognizes that stressors impacting childhood health and development are encountered across three broad areas: the built, natural, and social environments. Across these three realms, both chemical and non-chemical stressors contribute to children’s growth and development, oftentimes with long lasting impacts on health and well-being.

Two recent literature reviews show how EPA is advancing the total environment model as a new frontier in children’s environmental health research.

Cognitive Development

In a recent study,Exit EPA researchers used an encompassing model to examine environmental exposures and their links to children’s cognitive ability. EPA’s strategy includes equipping communities with tools and models that forecast the impact of real-world exposures to chemical and non-chemical stressors.

The study follows a total environment framework developed by EPA researchers to explore how the built, natural, and social environments together influence a child’s cognitive ability. The authors conducted a systematic review—mining three databases representing ten years of peer-reviewed studies—to identify epidemiological studies that examine chemical and non-chemical stressors associated with general cognitive ability in children. 

By establishing a set of criteria, the researchers homed in on the most relevant studies. This yielded 146 different papers (133 observational and 13 cohort studies) for more in-depth review. Collectively, a wide diversity of factors was identified across the studies that relate to cognitive ability, including: parental education level, gender, birthweight, breastfeeding, tobacco smoke exposure, family structure, chemical exposure, and other stressors.  In total, 150 studies investigated 110 possible stressors of cognitive ability.

Results of the research point toward what one would expect: that instead of any single study pinpointing a stressor or even a handful of stressors linked to cognitive abilities, the total environment contributes through a complex combination of exposures and events over time. The researchers conclude that such a holistic approach help illuminate “the true effects of key stressors that shape cognitive development.”

Childhood Obesity

In a similar effort, researchers used a total environment framework to conduct a systematic review for another high-priority children’s health issue: obesity. The Centers for Disease Control and Prevention estimates that childhood obesity affects 17% of all children and adolescents, a three-fold increase in just one generation. What role does the environment play in such a dramatic rise? EPA researchers conducted a novel study to explore how a total environment approach might help answer that question and ultimately contribute to solutions.

Like in the previously mentioned study, researchers began with an extensive literature review. They cast a wide net across the published scientific literature searching for stressors shown to influence childhood obesity, including individual behaviors, social determinants, the natural and built environments, and potential chemical exposures.

In the end, 234 articles were selected for more in-depth review and analysis, including the identification of contributing factors related to individual and family behaviors, community stressors, and chemical exposures. These ranged from diet and sleep, to prenatal exposure, access to nutritional food, chemicals known and suspected to cause obesity, and air pollution (including maternal smoking during pregnancy).

Like in the cognitive ability study, the researchers were not able to find a common stressor they could link to childhood obesity. “By better understanding the interactions of chemical and non-chemical stressor contributing to childhood overweight and obesity, we can begin to inform community decision makers on how to promote healthy, child-specific environments and provide solutions to improve overall community health and well-being,” the researchers conclude. 

The goal of this research is to provide solutions for improving community health, particularly for children and other vulnerable groups. Together, the two studies outlined above show both the need and promise of a holistic, total environment model for how to improve human health.

Sources and Citations:

Lichtveld, K., Thomas, K., & Tulve, N. S. (2018). Chemical and non-chemical stressors affecting childhood obesity: a systematic scoping review.Exit Journal of Exposure Science and Environmental Epidemiology28(1), 1.

Ruiz, J. D. C., Quackenboss, J. J., & Tulve, N. S. (2016). Contributions of a child’s built, natural, and social environments to their general cognitive ability: A systematic scoping review.Exit PLoS One11(2), e0147741.

Tulve, N., Tulve, N. S., Ruiz, J. D., Lichtveld, K., Darney, S. P., & Quackenboss, J. J. (2016). Development of a conceptual framework depicting a child’s total (built, natural, social) environment in order to optimize health and well-being.Exit Journal of Environment and Health Science2(2), 0-0.