Get something with Disodium Octaborate Tetrahydrate as an active ingredient. If it is mold or mildew this will take care of it. Mix it according to label for a 15% solution. Spray on spot just to moisten. Let dry, repeat once. Walk away, enjoy life.

It is a form of Borax, very stable and has a very low toxicity.

Oral LD50 is 2500 in Rats. .. .. .. Aspirin is 200.

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