Germana Carillo According to a new study, environmental pollutants leave a genetic imprint on humans even before birth and starting from pregnancy. What does it mean? That the harmful effects of smoking occur even 30 years after the last cigarette
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It may even be that, decades after quitting-even if medically one has rejoined the ranks of the nonsmokers-smoking changed your genes and set you up for diseases.
The conclusion emerges from a three-decade-long study published in the Journal of Cardiovascular Genetics and presented by Andrea Baccarelli, Dean of the Harvard School of Public Health, in the first International Conference on Environmental Medicine, organized by the Italian Society of Environmental Medicine at the “Gabriele D’Annunzio” University in Chieti-Pescara (Italy).
Actually, research has shown that the “epigenetic markers” of smokers – which refers to the changed “switches” of our genes – are never returned to the pre-smoking state even decades after quitting. These changes are partly associated with severe cardiovascular diseases among former smokers due to the increasing risks of heart attacks and strokes.
Environmental pollutants and genetic imprints
But it is not only tobacco that leaves such a significant genetic imprint. Environmental contamination plays a determining role in health, even from before birth, when the embryo is developing inside the womb.
Experimental studies performed on human placentas reflect distinct epigenetic modifications according to the pollutant profile of different cities, depending on whether it is dominated by vehicle emissions or industrial emissions, such as those from steel factories. “These epigenetic changes,” Rector of the University of Chieti, Liborio Stuppia, explains, “are the cause of the global epidemics of obesity and declining fertility that are spreading with incredible rapidity throughout the world due to the continuous interaction of environmental contaminants-heavy metals, bisphenol, microplastics, etc.-with our genetic component and starting from the womb or even before, in future parents’ germ cells.”
So, which ones are the main responsible pollutants? Unfortunately, we already know them:
- Heavy metals, among them, lead, mercury, and cadmium
- Organic chemicals, among them, pesticides
- Ultrafine particles PM2.5 mainly from urban traffic and industry
Exposure to these harmful agents has indeed been linked to an increased risk of chronic diseases, cardiovascular conditions, and neurodegenerative disease.
Today, changes to the epigenetic “switches” in our genes from endocrine-disrupting environmental pollutants are linked by scientists to 3.5 million cases of asthma worldwide. They are also behind the rising tide of diabetics, including children, who are increasingly falling victim to the disease, experts say.
