How Urban Planning Can Influence Child’s Neurodevelopment?

The worldwide growing urbanization is increasing the number of urban dwellers and projections show that 68% of the world population will live in urban areas by 2050. More people will be exposed to an adverse environment, including poor air quality, few access to natural spaces, and dense building areas, which poses a significant health risk on children.

The early-life –pregnancy and first years of childhood­– is considered to be a period of high sensitivity to environmental stressors, and perturbations during the development of the child may result in short- and long-term health consequences. According to the Global Burden of Disease (GBD) study, prevalence rates of mental disorders in European children have increased by 6% in the last two decades. Although such increase may reflect increased awareness of these disorders and broader diagnostic criteria, there is general concern on the possible implication of environmental factors.

The early-life –pregnancy and first years of childhood­– is considered to be a period of high sensitivity to environmental stressors, and perturbations during the development of the child may result in short- and long-term health consequences

Air pollution is a major environmental risk factor for various adverse health effects in humans, even at the lowest observable concentrations. The health effects of air pollution include, but are not limited to, cardio and respiratory disease, cancer, birth outcomes, and effects on the brain. According to numerous studies, air pollution have adverse effects on neurodevelopment, including increased risk autism spectrum disorder, higher attentional problems, and lower cognitive and motor function. Outdoor environment may also be beneficial for neurodevelopment.

While the number of studies about the effects of natural spaces on childhood mental health is still limited, it seems that green space exposure is beneficial to children’s behaviour and cognition. Nevertheless, previous research has not evaluated the impact of multiple exposure groups simultaneously using an exposome approach.

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We recently published a study to analyse the impact of the urban exposome on the cognitive and motor function of nearly 5,500 children in seven European urban areas—Bradford, United Kingdom; Nancy and Poitiers, France; Gipuzkoa, Sabadell and Valencia, Spain; and Heraklion, Greece. These results are part of The Human Early Life Exposome (HELIX) project, funded by the European Commission, and coordinated by ISGlobal, which brings together data from European birth cohorts including: Born in Bradford, EDEN, the INMA Environment and Childhood Project, and RHEA.

We recently published a study to analyse the impact of the urban exposome on the cognitive and motor function of nearly 5,500 children in seven European urban areas

We considered 13 urban residential exposures from pregnancy until age three years:

• Built environment: population density, building density, facility density and richness, land use diversity, density of street intersections, proximity to public transport and walkability.
• Natural spaces: surrounding greenness and proximity to major green and blue spaces.
• Air pollution: levels of nitrogen dioxide (NO₂) and fine particulate matter (PM_2.5).

We assessed motor function (fine and gross motor functions) and cognitive function (verbal and non-verbal abilities) using validated tests when the children were four to five years old.

In line with previous research, we observed that greater exposure to fine particulate matter during pregnancy was associated with lower scores on tests of fine motor function.

This is the first study to show that exposures to some built environment design factors were associated with children’s cognitive function at five years of age. Specifically, greater connectivity (i.e., density of street intersections) and land use diversity during pregnancy were associated with lower verbal abilities. We also confirmed that natural environments could have a beneficial effect on cognitive development by reducing the harmful effects of air pollution. Indeed, we observed that 75% of the positive effects of surrounding greenness on verbal abilities were mediated through a reduction of fine particle levels.

This is the first study to show that exposures to some built environment design factors were associated with children’s cognitive function at five years of age

As the world continues to urbanize, countries will face challenges in meeting the needs of their populations, including housing, transportation and basic services such as education and health care. City policies need to ensure access to infrastructure and social services for all, focusing on the needs of the most vulnerable populations, such as children, for housing, education, health care, and a safe environment. The health of the population should form the basis of urban planning.