Air pollution is responsible for 5.5 million of the 9 million deaths caused by pollution every year, making it the main cause of death by pollution in the world. Now, researchers have begun to understand the terrible effects air pollution is having on babies exposed to it in the womb.
The latest research, published in Environment International, looked at the DNA in umbilical cord blood from newborn babies born in Tongliang, China, before and after a coal-burning power plant was closed in 2004. Several findings suggest that the pollution has affected the children’s DNA.
The team observed that babies born before the plant was shut down had shorter telomeres than those born afterward. Telomeres are a specialized section of DNA that allows chromosomes to be copied faithfully. After each copy, during cell division, the telomeres get shorter. Eventually, the shortened telomeres lead the copies to be less faithful and this has been linked to aging, cancer, heart disease, cognitive decline, and even premature death.
The team confirmed that the shorter telomeres observed in those born before the coal plant shut down are associated with the presences of polycyclic aromatic hydrocarbons, a toxic component of air pollution from coal plants, and that they also led to a lower level of brain-derived neurotrophic factor, a protein involved in neuronal growth.
"An individual's telomere length at birth is known to influence their risk for disease decades later during adulthood," co-author Professor Deliang Tang, from Columbia Univerisity’s Mailman School of Public Health, said in a statement. However, "Further follow-up is needed to assess the role telomere length plays in health outcomes in the context of early life exposure to air pollution."
Out of the 255 children tested at birth in the study (half born before, and half after the shutdown), 210 were tested again at age 2 to check if the telomeres length was associated with neurodevelopment issues. They did not find any link, though this doesn’t exclude telomere length-associated development issues at a later age.
"The new study adds to the evidence that closing this coal-burning power plant was beneficial to the health and future well-being of newborns there," said lead author Professor Frederica Perera, director of the Columbia Center for Children's Environmental Health and professor of Environmental Health Sciences at the Mailman School of Public Health. "Moreover, we know that lowering exposure to air pollution anywhere will be beneficial to children's health and long-term potential."
The role of coal power plants in producing toxic fumes is undeniable and it is important to tackle this environmental danger to safeguard our health and the health of future generations.