[drypowder]

So sad, this same thing happened in California a few years ago witch prompted the federal EPA to impose strict usage guidelines for Aluminum and Zinc phosphide. Both are used as fumigants for insect control in storage grains and other ag seed commodities and for burrowing rodent control. It is dispensed in pellet or tablet form. The pellet/tablets are activated by ambient moisture and release pH3 (phosphine gas) over a period of days depending on the amount of moisture and how warm the temperature is. This pesticide is not applied as a spray. By attempting to wash the pesticide away from under the structure clearly caused the hastened release of the lethal concentration of phosphine gas. There is a minimum of 72 hour restriction to reenter the treatment sites. It is illegal in the US to use this pesticide within 100 feet of an occupied dwelling. Somebody is in deep do do.

[Axenolith]

“Wash it away after it was used under dwelling”?, that strikes me as odd. It’s a proscribed substance and I seriously doubt a licensed contractor would initiate this chain of events. I await news of the residents identity and wonder if someone wasn’t doing some experimenting in preparation for spraying for other than bugs...