Recent discussion continues about eating mushrooms from red fire foam areas
Several people have been talking about the safety of mushrooms growing in woods that have been recently sprayed with retardant. If any of you readers have comments or information about this, please post a comment or link.
A mushroom student and chemistry teacher here at the local college sent me this email reply to my question:
From Carol H.
“Wikipedia has a nice descriptive page on the foams that are used in firefighting, both for structural fires and for wildland fires: https://en.wikipedia.org/wiki/Firefighting_foam
I probably was overstating concern about the chemicals used in them when we chatted about this last night. I remember having a conversation with some fire science students a few years ago where they mentioned AFFF, which contains fluorinated organic chemicals (fluorine on a carbon backbone). That stuff is mentioned in the Wikipedia article and is a halogenated organic: a member of a family of compounds that raise a little environmental concern in me. There are some bad actors in that group.
BUT I was not correct in making them sound as bad as polychlorinated or polybrominated biphenyls. Those are the bad actors in that family, and are the compounds that are used in flame-retardants used in furniture.
The firefighting foams are mostly water and surfactants (detergents, soaps). The foam helps hold the water to the things that could burn, which makes them better than water alone. It looks like the red color may be from iron in the formula, added to aid visibility.
As far as foraging from places that have recently been foamed, I still probably wouldn’t do it.
Thanks for giving me a reason to look this up!”