Crawford's is free of added asbestos, white lead, mercury, tin, formaldehyde or any heavy metal biocide or fungicide. In addition, Crawford's Free contains no potentially harmful added silica - a most recent concern among health professionals. Crawford’s Free Spackling Paste is a multipurpose, premixed, ready-to-use vinyl-patching compound for use inside or out on primed plaster, drywall and wood surfaces.