science

Natural wildfires have been artificially intensified both by climate change, and humanity's obsession with not letting nature do its thing.

Wildfires are natural, they happened all the time without human intervention. Not like a constant thing, but often enough.

Humans moved in and decided if they see smoke on the horizon, it must be stopped. This kills the natural cycle that clears brush from the forest floor, and allows new life to bloom.

With forest floor scrub is basically at an all time high due to no small periodic fires, when it DOES burn, it really fucking blazes and creates insane conditions that basically wouldn't exist otherwise.

So yes, it DOES apply to natural wildfires, the wildfires wouldn't be so bad if humans didn't make them worse through mismanagement. Thus the contamination hazards would be less intense.