Here's what the experts had to say about how toast could be causing you damage:
“When you make toast, the heating element starts warming up the debris and gunk in the toaster which includes oils," says researcher Marina Vance, speaking at a meeting of the American Association of the Advancement of science.
“Add to that the bread itself — it’s going to emit a range of things. We found ethanol, a by-product of yeast," adds Vance.
“If there’s tiny pieces of bread touching the heating element you can see the smoke, maybe from crumbs at the bottom of the toaster — they will all make a lot of particles.
“It led to what would be considered ‘very unhealthy’ air pollution levels if compared to outdoor air quality standards.”
But the safest way to have your toast? Aim for a light brown.
When bread turns toasted golden brown, surrounding air contains between 300 and 400 micrograms of fine particulates per cubic metre. However, burnt toast is nearly ten times that amount, sitting between 3000 and 4000 micrograms per cubic metre.
The World Health Organisation recommends just 25 micrograms of fine particulates, putting burnt toast on par with busy crossroads.
If you think it's time to ditch the toast, here are some great healthy options for breakfast.