We Got Walnuts to the Face ...

St. Ives packs its Apricot Scrub with crushed walnut shells that can tear up your face, and leave you wrinkled with acne ... according to 2 women gunning for the skin treatment.

In a lawsuit the women filed, they say the supposed exfoliating facial scrub feels like sandpaper to the skin, with similar results. To back up their claim, they say dermatology research warns walnut shells to the face can cause inflammation leading to breakouts, and accelerated aging.

Their main beef is the St. Ives product says it's "dermatologist tested" -- which is misleading, they say, because it is tested ... but NOT recommended.

They've filed a class action suit against parent company, Unilever, for more than $5 million.