Air pollution impacts children’s health even before they are conceived. Studies reveal that women’s ovarian reserves are impacted by exposure to air pollution. According to a study on Chinese women, for every 10 μg/m3 increase in PM1, PM2.5, PM10 (PM – particulate matter), and nitrogen dioxide (NO2), the level of anti-müllerian hormone, a predictor of ovarian reserve, changed by -8.8 per cent, -2.1 per cent, -1.9 per cent, and -4.5 per cent.
Theoretically, PM with a larger surface area volume ratio and a smaller size, such as PM1 (diameter ≤1 μm), has a higher chance of passing through the alveolar capillary barrier and subsequently influencing ovarian function directly through blood circulation, according to a paper published in Environmental Research. Limited data suggests that oxidative stress and the inflammatory response brought on by air pollution may be one important pathway. Researchers are still unclear about the exact mechanism of female fertility decline induced by air pollutants.
Air pollution can interfere with a child’s growth in the womb if they are conceived against all chances, since it can enter the baby’s bloodstream through the placenta. Iranian researchers discovered an inverse association between the weight of the placenta, which supports the growth of the baby, and the amount of air pollution exposure during the first trimester of pregnancy, as per a study published in the Journal of Family and Reproductive Health in June 2017.
According to a thorough analysis of research that was published in The Lancet Planetary Health, black carbon particles found in cord blood can infiltrate the liver, lungs, and brain of the foetus. Pollutants continue to damage the developing foetus to such an extent that they are likely to raise the risk of premature birth. Consequently, this may raise the risk of stillbirth, low birth weight, undeveloped lungs, and infant mortality during or soon after birth.
Pollution prevents pregnant women from getting adequate oxygen from the surrounding air, which has an impact on the foetus’s normal development. A miscarriage is also more likely to occur when the air contains more sulphur. Numerous studies demonstrate that exposure to pollutants both before and after birth can affect a child’s neurodevelopmental abilities, including verbal language, intellectual functioning, memory and learning, attention and executive functions, motor and/or sensor motor functions, and numerical ability, even if the child survives the onslaught of pollutants in the womb.
As with adults, exposure to air pollution during pregnancy is known to cause a child’s blood pressure to skyrocket; the higher the newborn’s systolic blood pressure, the higher the mean exposure to PM2.5 and black carbon during the third trimester. In addition to making survival challenging, prenatal exposure to air pollution can cause congenital cardiac abnormalities in offspring, it does not spare the lungs either. Higher levels of air pollution exposure during infancy have been found to reduce lung capacity. Children who are exposed to higher levels of PM2.5 also appear to be more susceptible to acute respiratory illnesses. A 10 μg/m3 rise in PM2.5 was linked to a higher risk of illness, according to a sample of children under five years.
The composition of gut microorganisms is negatively impacted by pollutants absorbed during the first six months of life, which may raise the risk of allergies, obesity, and diabetes as well as have an impact on brain development. According to a 2020 study in gut microorganisms, these microorganisms and their byproducts influence immunity, mood, appetite, insulin sensitivity, and cognition. A young child with a poor microbe mix may be more susceptible to type 2 diabetes, asthma, and other chronic diseases.
Prenatal exposure to air pollution can potentially alter the baby’s protein activity. For instance, according to a paper presented at the European Respiratory Society International Congress in Milan, Italy, pollutants have been discovered to impact cell processes like autophagy, or the ‘self-eating’ of damaged cells that typically happens in reaction to stress. Reduced levels of SIRT1, a protein that protects against stress, inflammation, and ageing, were associated with increased NO2 exposure.
Additionally, there is growing evidence on the health effects of pollution sources. Studies conducted in Europe have looked into how vehicle pollutants affect the development of neurones residing beside highways and the health of children. A 2013 study discovered a link between a number of juvenile malignancies and early exposure to road pollution.
Adolescent girls’ reproductive health is similarly impacted by air pollution exposure, as if to complete the vicious cycle. Because particulate matter particles appear to have endocrine-disrupting qualities, higher exposure to them during pregnancy and childhood has been linked to an earlier menarche.
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