Air Pollutants: How They Affect Our Babies' Health

Children are more vulnerable to air pollution than adults. Their bodies and organs are still developing, and they have weaker immune systems. They also breathe in more air per kilogram of body weight and tend to spend more time outdoors and be more physically active than adults.

Air pollution affects children from the womb to adulthood and increases the risk of diseases later in life. It is linked to low birth weight, asthma, reduced lung function, respiratory infections, allergies, and cognitive impairment.

The main sources of air pollution in Europe are traffic, heating, and industry. While emissions have declined, air pollution levels are still unsafe.

To protect children's health, air quality policies should explicitly consider their unique vulnerabilities and exposure pathways. Reducing exposure to air pollution in child-centric settings, such as schools and kindergartens, can help mitigate the risks.

Low birth weight

Pregnant women and their foetuses are sensitive to air pollution due to the physiological changes that occur during pregnancy. Exposure to air pollution during pregnancy has been linked to an increased risk of low birth weight. Fine and ultrafine particulate matter, a major component of ambient air pollution, is particularly harmful to children's health as it can directly cross the placenta, reaching the fetal circulation.

In a study in Iran, there was a direct and significant relationship between exposure to PM10 and low birth weight. Another study in China found that maternal exposure to air pollution during pregnancy was associated with an increased risk of low birth weight, especially in the first trimester. A study in the US also found a positive association between air pollution and low birth weight.

Maternal exposure to fine and ultrafine particulate matter has been found to yield numerous adverse birth outcomes. A study in Mongolia showed that exposure to PM10 was associated with a 12.2g weight reduction in newborns. Another study in the US found that children exposed prenatally to air pollution had lower birth weights and were more prone to rapid weight gain in the first six months of life.

In addition to the direct effects, air pollution can also indirectly affect low birth weight by causing placental and systemic maternal oxidative stress and inflammation, as well as epigenetic changes.

Preterm birth

Air pollution is associated with an increased risk of preterm birth. Preterm birth is when a baby is born before 37 weeks of gestation. It is a leading risk factor for death in the first month of life and increases the risk of health problems such as lower-respiratory infections, diarrhoeal diseases, brain damage and inflammation, blood disorders, and jaundice.

Risk Factors

Several factors can contribute to preterm birth, including having multiple babies, aspects of the mother's health, and sociodemographic factors. People who live in polluted areas or have exposure to indoor air pollution from toxins such as cigarette smoke have higher rates of preterm birth.

Pollutants

The effects of air pollution on preterm birth are thought to be analogous to tobacco smoking, a well-known risk factor. The specific pollutants that cause preterm birth include:

• Particulate matter (PM)
• Sulfur dioxide (SO2)
• Nitrogen oxide (NOx)
• Ozone (O3)
• Carbon monoxide
• Lead

Preventing Negative Effects

To reduce the effects of air pollution on preterm birth, people can:

• Evacuate to a safer area when air quality is very dangerous
• Install a carbon monoxide detector
• Install a high-efficiency particulate air filter
• Talk to a medical professional about other tips to reduce the risk

Respiratory infections

Children are more susceptible to the adverse effects of air pollution due to various physiological and behavioural factors. They have a higher breathing rate and breathe more air per unit of body mass than adults. They also tend to spend more time outdoors, engaging in physical activity such as play, and have less efficient nasal filtering than adults.

Children exposed to air pollution are at a higher risk of respiratory infections, including acute respiratory infections, bronchitis, bronchiolitis, pneumonia, and upper respiratory infections.

Several factors can contribute to low birth weight and preterm birth, which are leading risk factors for death in the first month of life. Being pregnant with more than one baby and various aspects of a mother's health, including chronic health conditions, malnutrition, and tobacco use, can play a role.

Household air pollution accounts for most pollution-attributable newborn deaths. Globally, pneumonia is the largest cause of death among young children.

Asthma

Outdoor Air Pollution

Outdoor air pollution is a mix of harmful gases and particles in the air we breathe. In towns and cities, the main source of air pollution is traffic. Other sources include the air inside your car, chemicals used for cleaning, building materials, damp and mould, and smoke from tobacco, cannabis, or vaping.

Pollutants in the air irritate the airways, causing them to swell and tighten up, and leading to breathing problems. They can also make children more likely to catch upper respiratory infections, which can bring on asthma symptoms.

Ground-Level Ozone

Ground-level ozone is formed when chemicals from cars, power plants, and factories mix with sunlight. It is a major component of smog and can harm the lungs. Particle pollution is created when tiny bits of dust, dirt, smoke, soot, and other substances hang in the air, for example, from wildfires. The smaller the particles, the deeper they can get into the lungs and cause breathing problems.

Other Pollutants

Other pollutants include gases such as carbon monoxide, nitrogen dioxide, and sulfur dioxide, which come from burning different types of fuels. High levels of these gases can affect lung function.

How to Protect Babies with Asthma from Air Pollution

• Check the Air Quality Index and pay attention to pollution levels.
• On days when air quality is poor, run the air conditioning and limit your child’s outdoor activities if possible.
• Plan any outdoor activities for early in the day when air quality tends to be better, and avoid spending time in areas with a lot of traffic.
• If you must spend time in a car, close the windows and vents and run the air conditioning instead.
• Talk to your child's coach about other arrangements if they play sports outside during hot weather.
• Make sure your child always has their quick-relief medicine on hand.
• Improve the air quality in your home by using an air cleaner, venting all gas appliances to the outside, and avoiding wood fires.
• Talk to your doctor about increasing your child's medicine during times when air pollution is high.

Lung function

Air Pollutants

Air pollution is a mixture of solid particles and gases in the air. Outdoor air pollution comes from cars, factories, forest fires, and construction sites. Indoor air pollution comes from stoves, fireplaces, cigarettes, and cleaning products.

Effects of Air Pollution on Lung Function

Air pollution has been shown to have adverse effects on lung function in children. Short-term exposure to air pollution has been linked to lower lung function in healthy children and those with asthma. Long-term exposure to air pollution has been linked to lower lung function in children, which may shift the entire population distribution of childhood lung function downward.

Pollutants and Lung Function

Fine particulate matter (PM2.5) and nitrogen dioxide (NO2) have been linked to lower lung function in children. Ozone (O3) has been linked to lower lung function in healthy children and those with asthma. Particulate matter with an aerodynamic diameter less than 10 μm (PM10) has been linked to lower lung function in children, but the evidence is less robust.

Infant Lung Function

Air pollution exposure during infancy affects lung function later in life. Exposure to air pollution during infancy has been linked to impaired lung function measures related to both airway calibre and lung volume. Lung function in infancy can be measured by infant spirometry, which includes plethysmography and raised volume forced expiratory flows.

Prenatal and Postnatal Exposure

The effects of prenatal and postnatal exposure to air pollution on lung function cannot be separated due to high correlations in exposure between the two periods. However, studies suggest that long-term exposure is more important for adverse lung function effects than short-term exposure.

Frequently asked questions