Crutlins

unidentifiable crumbs, may or may not be food, may or may not be toxic

"Clean out your car, the floor is covered in crutlins."

Froegy

Moist and slightly rotten

"There's a froegy old piece of wedding cake in that puddle."

Scunge

sticky and dirty; like old gum in a dusty parking lot

"I dropped my phone in the gutter and now there's scunge all over it."