Wildfires are once again tearing through parts of southern Europe, with Greece, Portugal and Spain all battling major blazes.

But in one area west of Athens, residents fear the danger is not only the flames — it is what burns with them.

In Mandra-Eidyllia, a municipality close to Aspropyrgos, one of Greece's major industrial zones, wildfires can sweep through dry land, forest, homes, warehouses, factories and recycling facilities. When that happens, doctors warn the smoke may carry more than ash.

For local resident Sotiris Lioris, wildfire season has become a fight for breath.

Inside his home, he keeps a mask close by. Pills are lined up on the table — medication for his heart, his lungs, and the condition that changed his life after major surgery in 2023.

Sotiris has a heart valve and breathing problems. His cardiologist has given him one clear warning: when smoke comes close, stay away.

"When it comes to my breathing, I get shortness of breath and tachycardia," he says. "And I can also hear the valve."

His fear is shared by doctors in the area.

The mayor of Mandra-Eidyllia, Armodios Drikos, is also a cardiologist. He has treated many patients locally and says the health danger does not disappear once firefighters put out the flames.

"A fire, a wildfire, and its consequences do not end when the fire is extinguished," he says. "The particles emitted by wildfires burden the atmosphere for many months."

Nightmare scenario

Authorities in Greece recently warned residents to stay indoors after toxic smoke spread from a burning recycling facility. For communities close to industrial zones, that is exactly the nightmare scenario.

A wildfire may begin in forest or scrubland, but if it reaches factories, cars, plastics, warehouses or recycling sites, the smoke can become far more dangerous.

Doctors say ordinary forest fires release fine particles from burning trees and vegetation. But when industrial materials burn, those particles can mix with chemicals and toxic substances, creating an invisible threat for nearby communities.

Children, the elderly, asthma patients, and people with heart or lung conditions are among the most vulnerable.

Toxic

Standing near industrial buildings in Mandra-Eidyllia, the fear is clear: a fire here would not only burn land and property. It could send toxic smoke into homes, schools and streets.

Drikos says part of the danger is that people often trust the air simply because they cannot see what is in it.

"Air has a sly little secret: you cannot see it," he says. "You may feel that it is clean, but you do not perceive what you are breathing in."

The advice from health experts is simple: stay indoors, close windows, use filtered air where possible, wear a mask if exposure cannot be avoided, and stay away from burned areas even after the flames are gone.

For Sotiris, that warning is now part of everyday life.

In places like Mandra-Eidyllia, where homes sit near factories and fire-prone land, wildfire season leaves behind more than scorched earth.

It leaves a second emergency — toxic air, invisible particles, and vulnerable people still holding their breath.