It's not the heavy metal poisom that kills you, it just shuts down your nerve cells from restoring its membrane potsntial.
It's not corona that causes you to die from suffocation, it'z just the immun response that results in changes to the mitochondria, powerhouses of the cell, and shortness of breath.
It's not the cancer that kills you, it's the organ failure!
Depth is irrelevant. Distance differs here.