Short answers, pulled from the story.
Exfoliation in cosmetology is the removal of dead surface skin cells and built-up dirt from the skin's surface. The term derives from the Latin word exfoliare, meaning to strip off leaves.
Exfoliation was first practiced among the ancient Egyptians, who used animal oils, alabaster, salt, and sour milk as a chemical exfoliant. The practice also spread to Greek, Roman, Turkish, Indian, and Hungarian civilizations, and was recorded in China during the Qing Dynasty, which lasted from 1644 to 1912.
Mechanical exfoliation tools include microfiber cloths, adhesive sheets, microbead scrubs, pumice stone, sugar or salt crystals, sponges, loofahs, brushes, and exfoliation nets made of knotted nylon mesh. Loofahs are made from the dried fibers of the luffa gourd, while exfoliation nets are native to Ghana.
Microbeads, typically made of polyethylene terephthalate, measure less than one millimeter and are too small to be filtered by sewage treatment works, releasing large amounts of plastic into marine ecosystems. In June 2014, Illinois became the first American state to ban them, and manufacturers including L'Oreal, Johnson and Johnson, and Colgate committed to replacing them with natural alternatives.
Dermaplaning is an exfoliation procedure in which a single-blade razor called a dermatome is drawn across the face to remove dead skin cells and fine vellus hair called peach fuzz. Dermaplaning specialists state that the removal of peach fuzz does not affect the growth, color, or texture of facial hair; the claim that it causes thicker regrowth is a misconception.
Chemical exfoliation peels use alpha-hydroxy acids such as glycolic, lactic, mandelic, malic, tartaric, and citric acid; the beta-hydroxy acid salicylic acid; polyhydroxy acids including lactobionic acid, gluconolactone, and galactose; and enzymes such as trypsin or collagenase. Only alpha-hydroxy acids and beta-hydroxy acids are approved for daily consumer use.
Dermatologists state that chemical or manual exfoliation is not medically necessary, as dead skin cells already shed naturally on their own. Excessive artificial exfoliation can break the skin's barrier against microorganisms, leading to infection, tightness, and sensitivity, and can worsen dry or flaky skin rather than improve it.