Toddlers putting things into their mouths, school-aged children playing in a schoolyard and teenagers walking to school through traffic are all physical interactions with their immediate environment. Children need to explore physically to grow, by exploring through their five senses. But what if the air and water they use and live in are only harming the child?
Pollution is often referred to in reference to glaciers melting, increased global temperatures, erosion of ecosystems, etc. But the cumulative effects of pollution on a child’s well-being occur slowly and insidiously, and are rarely noticed in time to prevent further harm. It accumulates, settling into the background of everyday life, long before anyone thinks to connect it to the environment they grew up in.
Research across many branches, including psychology, neuroscience, environmental Health, etc, has shown that pollution has the potential to change children’s cognitive, emotional and psychological development, as well as affect their ability to adapt (Suades-González et al., 2022). The effects of pollution during early childhood may not always be apparent immediately; instead, they will gradually add up over time, affecting a child’s attention span, ability to learn, emotional regulation and mental health into adolescence or adulthood.
Read More: The Adverse Effects of Air Pollution on Mental Well-Being
Why Children Are Especially Vulnerable
Children are not just “small adults.” Their bodies and brains have not developed as far as adults’, and, as a result, they are more sensitive to environmental stressors. For example, if an adult and a child are walking down the same polluted street, the child breathes in more air, proportionately to their weight, than the adult does, because the child is closer to ground level and because the exhaust fumes are at ground level and can therefore be inhaled by the child. An irritation that an adult may perceive to be mild can be a chronic exposure for a child. Children are different from adults because:
- They breathe faster than adults; therefore, they will inhale more oxygen per pound of body weight
- They spend more time outdoors near ground level, where most of the pollutants can be found
- Have immature immune and detoxification systems
- In the first five years of life, they have a significantly more rapid brain growth rate than at any other period in a person’s life.
As a result, a bustling urban street may cause preschoolers to have many more respiratory problems and chronic fatigue due to air contaminants. These exposures will affect the direction of children’s development over long periods of time (Grandjean & Landrigan, 2014).
Read More: The Growing Impact of Air Pollution on Mental Health
The Developing Brain
A huge no. of studies indicate that one of the most serious threats to children’s growth and development is from air pollutants. Transportation-related pollutants, including fine particulate matter, nitrogen dioxide, ozone, as well as black carbon, are the main contributors.
Pollutants don’t stop at the lungs. Fine-grained particles are small enough to travel through the blood to other organs and may also pass through the blood-brain barrier and reach the brain. When these enter the brain, they can interfere with proper synaptic communication between neurons and result in improper neuron response or activation.
There are a few important biological mechanisms
- Neuroinflammation: Pollutants can trigger a chronic neuroinflammatory response in the brain.
- Oxidative Stress: Toxic Particulate Matter that can penetrate the blood-brain barrier, damages the neurons, causing impaired brain development.
- Structural Brain Changes: A significant number of neuroimaging studies (Block & Calderon-Garcuena, 2009; Suades-Gonzalez et al., 2022) indicate structural brain changes (i.e., global and regional decreases in cortical thickness) associated with exposure to elevated concentrations of air pollution in children.
The same influences also play a large part in shaping emotions and making decisions; therefore, children exposed to continuous pollution may lack impulse control and will express their feelings in a much larger way.
To illustrate, picture a child being raised near a busy road and attending a nearby school located on the road itself. Even when they are sitting in class, their body are being exposed to tiny particles from the exhaust of vehicles, seeping in through windows and doors. This daily and yearly exposure becomes a regular part of this child’s learning environment. Several studies have found that children who are exposed to higher levels of air pollution perform lower on Attention and concentration, Working memory, Processing speed and Academic achievement.
A large-scale review of systematic research has established consistent associations between children and adolescents exposed to a high level of PM₂.₅ and NO₂, and poor cognitive performance (Forbes et al., 2020). Additionally, longitudinal studies have shown that children who attend schools located in areas with high levels of pollution experience slower cognitive development over time, especially in the areas of working memory and executive function (Sunyer et al., 2015). These are not trivial skills. Executive functions are important for children to learn to effectively manage their educational tasks, social relationships, emotions, etc, thus impacting long-term success.
Read More: The Impact of Pollution on Workplace Productivity and Mental Well-Being
Emotional and Behavioural Consequences
Cognitive outcomes are not the only aspect of pollution exposure. There is considerable evidence that suggests that pollution exposure impacts children’s emotions and behaviour. Researchers have discovered that there is a strong link between exposure to air pollution and increased levels of anxiety or depression, increased incidence of emotional dysregulation, and increased risk of conduct disorder behaviours. As a result of long-term ongoing exposure to highly polluted areas, many parents of young children report seeing increased levels of irritation and anxiety in their children.
Many of these emotional responses are attributed to either parenting style or temperament; however, environmental stressors can go undetected and contribute to the overall effect on children. Research shows that children living in areas where the levels of PM₁₀ and NO₂ are higher, develop behaviour and emotionally-related problems at a significantly higher rate compared to other children, even after controlling for other socioeconomic factors, such as family income (Roberts et one, 2019).
These results hold for both urban (cities) and rural (country) settings. For example, the same pattern of findings in rural areas has been shown for children who are exposed to agricultural burning, challenging the idea that pollution-related mental health risks are limited to cities (Zhang et al., 2024).
When Harm Begins Before Birth
One of the most alarming findings within this research area is that an individual may have negative exposure to pollutants before birth. A pregnant person living near heavy commercial traffic or industrial facilities can have healthy physical development and normal growth of a fetus. However, pollutants inhaled by them daily can cross the placenta and enter the developing fetus.
The fetal brain develops at an incredible rate during pregnancy. There is evidence to suggest that exposure to air pollution negatively impacts brain growth/development and morphogenesis of the brain during pregnancy by disrupting the normal process of neuronal migration, synapse formation and gene expression in the fetal brain (Perera et al., 2019). To date, there is consistent evidence that prenatal exposure to air pollution correlates with Lower IQ scores in childhood, Delays in language and motor development and increased risk of neurodevelopmental disorders, including ADHD and autism spectrum conditions (Volk et al., 2013).
Beyond Air
Air Pollution is only one component of an overall toxic environment in which children grow up. For example, lead Exposure from lead-based paint, contaminated drinking water, and soil has been closely associated with cognitive impairment and behavioural issues. When a child consumes water that has been delivered by a pipe that has reached the end of its life expectancy, they may not have any immediate negative impacts, but may wind up with poor academic performance and impulsive behaviour years later.
Even at low levels, lead exposure is linked with Reduced IQ, Poor impulse control and increased aggression and emotional problems (Lanphear et al., 2005). For a child, no amount of lead exposure is safe, unlike many other hazardous substances. Organophosphate pesticides commonly used in agriculture are also contributing factors to these issues. Attention deficits, Memory problems and increased risk of developmental delays (Rauh et al., 2011).
A youngster who lives in an agricultural area might encounter organophosphate pesticides as a result of the crops they consume, the air they breathe, or the dust that enters their house due to the clothing that they wear, which illustrates how environmental risks typically accompany families into the home.
Role of Socioeconomic Inequality
Children experience very different exposures to environmental pollutants. Lower-income children have a higher likelihood of:
- Being around significant highways and industrial facilities
- Attend poorly funded schools in polluted areas
- Have limited access to health care and protective resources
Environments of low-income children typically provide multiple sources of stress, such as overcrowding, noise, financial stress and pollution. All these factors together increase a child’s risk for poor developmental outcomes and reduce their chances of success (Evans and Kim, 2013).
Long-Term Implications
Early exposure to pollution affects a child throughout their lifespan. While research links pollution exposure during childhood to Lower educational attainment. Mental health issues during adolescence and lower economic productivity as an adult. For example, if a child’s attention and concentration are impaired due to neurodevelopmental disruption caused by pollution during childhood, likely, they will likely not do well in school, and this will carry over into their future occupational opportunities.
Hope, Prevention and Action
Although the research is troubling, it has also been used to implement solutions.
1. At the Policy Level:
- Improved air quality standards.
- Safer limits for industrial emissions
- Environmental protections for schools and residential areas
2. At the Community and Family Level:
- Improving indoor air quality
- Reducing exposure to known toxins
- Advocating for cleaner, safer neighbourhoods
Making even small modifications to the environment, such as changing to more appropriate cooking fuels and providing greenery around schools & other community spaces, can promote positive developmental outcomes in children.
Protecting Minds Before They Bloom
Children do not choose where they live. Yet, where they are raised forms the basis for their minds, feelings and future development. The literature supports the argument that environmental toxicity will have consequences on cognitive and emotional growth. These consequences may remain unrecognised for years after children are removed from toxic environments. Thus, addressing pollution is a way to help protect childhood itself.
If we care about education and the mental well-being of all children, and developing their full potential as human beings, we have to view clean air, safe drinking water and a non-toxic living environment as basic human rights, not mere privileges. Every child should have the opportunity to grow up breathing clean air, thinking independently and feeling secure in their environment.
References +
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