This is by mass, which is a weasel metric that discounts all gaseous emissions, and the smallest particulates that stay in the air.
Impact on health is not linearly proportional to the mass.
It's almost the opposite - the smallest particles can linger in the air and get absorbed.
You could eat a chunk of a tire without a significant health effect, but breathing the same mass of almost any gas would kill you.
Impact on health is not linearly proportional to the mass.
It's almost the opposite - the smallest particles can linger in the air and get absorbed. You could eat a chunk of a tire without a significant health effect, but breathing the same mass of almost any gas would kill you.