For basic nontoxic stain removal, mix up a little grandmother knowledge and apply it liberally.
The principles behind creating stain removers -- or nearly all household cleaners -- are relatively simple. Some kinds of stains respond to alkaline minerals such as borax and soap, others to acids like vinegars.

This bit of "grandmother knowledge" is used to formulate not only the nontoxic cleaners made from kitchen-cabinet ingredients, but also many modern chemical home cleaners. Whether for health or home, those folk remedies that have stood the test of time have generally been based on sound chemistry.

Formulas concocted using grandmother knowledge work perfectly well for removing stains. There is no reason to use anything toxic; with a few natural ingredients, you can solve even the toughest problems.