Mold on wood penels?

I live near Los Angeles, Calif. It rained for many days non-stop, here.
Today I discovered many of the normally white wood ceiling and side panels have black dirty spots in our outdoor screened Lani room. 1/2 of a wooden panel is black with this stuff.
My first guess is this is a mold. When I wipe the dirty spot with water on cloth. Cloth turned dark like plain old dust.
Wiped another dirty panel with bleach water. Samething, dirt came off making cloth black.
Further, the normally white wood panel has an off-white color in the areas where I wiped away the black stuff. Could these panels be be damp or wet?
Is this mold or something else?
How should I clean these panels? Should I wash each with a bleach water solution?
Thanks for any suggestions.
Dave_s
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Sounds like mildew, mold, or soot. Get some benadryl in case of adverse reactions and smell the stuff (don't *SNORT* it). You should be able to tell if it's mildew or mold.

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Bleach is not the first line of defense, use something like the drugstore brand of Listerine. It has Thymol as the antiseptic.
You also might want to air the place out as much as you can. If the place dries out it won't come back.
--

Roger Shoaf

About the time I had mastered getting the toothpaste back in the tube, then
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