I don't know, nor do I need to know in order to be justified in rejecting your bare assertion as such.
Do you recall Dave Roger's "Unevaluated Inequality Fallacy"?
It states that a claim of the form "A is greater than B" is not validly made out if you cannot provide justifiable
values for
both A and B, or at least a lower bound for A and an upper bound for B.
You claim:
"The amount found, in dust samples could not have been simply cause by fires, but thousands of welding rods were used in the buildings."
This is two unevaluated inequalities:
- A > B, where A is "The amount (of iron microspheres) found, in dust samples" and B is "the amount (of i.ms. in the dust) that could have been caused by the fires". But what is A, and what is B? Without giving us values for a lower bound for A and an upper bound for B, you cannot verify that your claim is true - it is not made out and thus rejected by me
- C > A, where C is the amount of microspheres released into the WTC dust by "thousands of welding rods [that] were used in the buildings". Even if we accept for a moment the claim of "thousands" of welding rods (does this imply "less than 10,000" or "less than 20,000"? For you could have said "tens of thousands", if the number was larger than 10,000 or 20,000), you have not made out an argument that gives you a lower bound for the amount of microspheres in the dust from that process. And A again would be the unevluated amount of microspheres found in the dust.
So please, do a little work here to justify your two claimed inequalities by calculating or at least estimating reasonable upper/lower bounds for the various oberved or possible amounts of microspheres in the dust that you allude to.