First try to fix the problem
Before doing anything fix the line so it does not come back.
Once done see if their is mold on the walls or anywhere else.
If alot then may be some remediation is needed. You can read the Mold Manuscript for this... or hire a pro.
If you need a product Safe Shield and Molderizer are organic and come in a kit these product will remove and create a barrier on the wall so no more future mold can grow.