Air Pollution's Impact On Unborn Babies: A Concerned Look

Air pollution is a mixture of toxic components, including carbon monoxide, nitrogen dioxide, sulphur dioxide, ozone, lead, polycyclic aromatic hydrocarbons, and particulate matter. It is an issue that affects people worldwide, with 90% of children exposed to air pollution above World Health Organization guidelines. Evidence suggests that air pollution can have a detrimental impact on unborn babies, increasing the risk of low birth weight, preterm birth, congenital malformations, intrauterine growth restriction, and neonatal mortality. In addition, exposure to air pollution during pregnancy has been linked to an increased risk of preeclampsia, hypertension, and gestational diabetes. These complications can have both immediate and long-term effects on the health of newborns, with low birth weight and preterm birth being leading risk factors for death in the first month of life.

The impact of air pollution on unborn babies is a growing concern, with studies suggesting that it may be contributing to a global health catastrophe. With millions of babies worldwide potentially being harmed by toxic air, there is an urgent need for action to reduce pollution and protect the health of pregnant women and their babies.

Low birth weight

Exposure to air pollution during pregnancy has been linked to an increased risk of low birth weight in newborns. Low birth weight is defined as a weight below 2500 grams in newborns. It is a significant marker of a newborn's health status and is directly linked to infant mortality rates.

Several studies have found a direct and significant correlation between exposure to air pollutants, particularly particulate matter (PM), and low birth weight. PM is a complex mixture of microscopic particles and liquid droplets composed of nitrates, sulfates, organic substances, metals, and dust particles. The specific pollutants that have been associated with low birth weight include:

PM10

Preterm birth

Exposure to air pollution during pregnancy is linked to an increased risk of preterm birth. Preterm birth is defined as giving birth before 37 weeks of gestation, and it is a leading risk factor for death in the first month of a newborn's life. According to a study by The Stockholm Environment Institute (SEI) at the University of York, air pollution is linked to approximately three million preterm births annually, accounting for 18% of all preterm births worldwide.

Babies born prematurely are at a higher risk of neurological disorders and permanent physical disabilities. They are also more susceptible to health problems such as lower-respiratory infections, diarrheal diseases, brain damage, blood disorders, and jaundice. The smaller the baby or the earlier they are born, the higher the risk of complications during infancy and early childhood. These complications can include infectious diseases and major chronic diseases later in life.

The exact biological mechanisms by which air pollution increases the risk of preterm birth are not yet fully understood. However, it is speculated that air pollution may affect pregnant women and their developing fetuses in ways similar to tobacco smoking, which is a well-known risk factor for preterm birth.

To reduce the risk of preterm birth, it is recommended that pregnant women limit their exposure to air pollution, especially during the early and late stages of pregnancy. This can include staying indoors when outdoor air pollution levels are high, using air purifiers, and avoiding exposure to second-hand smoke. Additionally, policy interventions are needed to improve air quality and reduce pollution from vehicles and other sources.

Autism

Recent studies have found a link between exposure to air pollution and the risk of ASD. Air pollution consists of various pollutants, including particulate matter (PM), nitrogen dioxide (NO2), and volatile organic compounds (VOCs). These pollutants can enter the body through the respiratory system and may have neurotoxic effects, particularly during prenatal and early postnatal stages when the brain is still developing.

Several studies have found associations between exposure to air pollution during pregnancy and the development of ASD in children. For example, a study published in the *Journal of the American Medical Association (JAMA) Pediatrics* reported a positive correlation between exposure to NO2 during pregnancy and the likelihood of an ASD diagnosis in children. Another study found that exposure to PM2.5 during pregnancy was associated with an elevated risk of ASD in children.

The exact mechanisms through which air pollution might influence the development of ASD are still being studied. However, some potential pathways include inflammation and oxidative stress, disruption of neurodevelopment, and epigenetic modifications.

It is important to note that while these studies indicate a potential link between air pollution and ASD, they do not establish a direct cause-and-effect relationship. More research is needed to confirm the association and understand the specific pollutants and mechanisms involved.

By identifying and addressing environmental factors such as air pollution, it may be possible to reduce the risk of ASD and improve overall well-being for individuals with ASD. Additionally, strategies to minimise exposure to air pollution and advocate for clean air and environmental regulations can also help reduce potential risks.

Asthma

Air pollution is a mix of harmful gases and particles in the air. It is not just restricted to outdoor air, but also affects the quality of indoor air. Exposure to air pollution in the womb can affect a baby's lung development and increase the risk of premature birth and low birth weight.

Children are more vulnerable to breathing in polluted air than adults because their airways are smaller and still developing. They are also more susceptible because they are usually closer to the ground or at face level with car exhausts and cigarettes.

Air pollution can trigger asthma attacks and make symptoms worse. It can also cause children to develop asthma during childhood or as an adult. If a child already has asthma, air pollution can worsen their condition.

African American adolescents are more vulnerable to air pollution than other children. A study found that low levels of outdoor ozone were associated with respiratory changes and other outcomes in African American children with difficult-to-treat asthma, even when they used asthma therapies such as inhalers to modify the adverse effects of air pollutants.

A study by Johns Hopkins University found that children exposed to outdoor coarse particulate matter were more likely to develop asthma and need emergency room or hospital treatment. Coarse particulate matter can come from roadway particles such as brake and tire wear, and mixtures of road dust and metals.

Another study found that exposure to air pollution may impact DNA associated with asthma. Evidence suggests that air pollutants suppress genes that regulate the immune system's ability to differentiate an allergen from a dangerous foreign substance, such as a virus or bacteria. The immune system then goes into action, setting up an inflammatory response whether the substance is harmful or not, which leads to asthma.

Traffic-related air pollution, nitrogen dioxide, and second-hand smoking are significant risk factors for asthma development in children. Active tobacco smoking is associated with poorer asthma control, while exposure to second-hand smoke increases the risk of asthma exacerbations, respiratory symptoms, and healthcare utilization.

Ways to Protect Yourself From Air Pollution While Pregnant

• Read the Air Quality Index (AQI)
• Get an air purifier
• Protect your air by using natural household cleaners, using your vent hood when cooking, doing routine checks for mold, and using carbon monoxide detectors
• Stay inside when the forecast is telling you to watch for outdoor air pollution
• Get air-purifying plants

Fertility problems

Air pollution has been linked to fertility problems in both men and women, according to multiple studies. Some research also suggests a link between air pollution and miscarriages.

A study conducted in London, UK, found that air pollution significantly increases the risk of low birth weight in babies, which can lead to lifelong health issues. The research showed a 15% increase in the risk of low birth weight for every additional 5 micrograms per cubic metre (µg/m3) of fine particle pollution.

Similarly, a study in Beijing, one of the world's most polluted cities, found that lowering emissions and improving air quality resulted in heavier birth weights for babies born to women in their eighth month of pregnancy during the 2008 Olympics.

The impact of air pollution on fertility and pregnancy outcomes is a growing area of concern, with researchers calling for urgent action from governments to reduce pollution from vehicles and other sources.

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