Highly unlikely.
Black lung disease is a specific medical condition developed by coal miners, usually after decades of exposure.
I have no clue what mercury on the brain is, but I'm sure it's not a specific disease.
While there may have been significant total amounts of mercury released when the Towers collapsed, any one person is likely to only have been exposed to minute quantities. In addition, the mercury released would probably have been in elemental form, which is relatively harmless, not the organic forms that cause serious poisoning in low doses.
If he didn't wear appropriate protective gear he was perhaps brave but foolish. I sincerely hope much more work has gone into preparing for such catastrophes in the future. Yes rescues are important but are they worth the additional cost in lives due to ill equipped, improperly trained "heroes"?
His death is senseless and, apparently, he leaves behind an orphaned child. There's probably more cases like his to come if indeed his death is traceable to exposure at the WTC site.
Exactly!
The story is BS....