From Agro-Industrial Residues to Dermocosmetic Exfoliants: A Narrative Review of Sustainable Ingredients

Physical exfoliating ingredients are used in cosmetic formulations to remove loose and/or senescent corneocytes, improve skin texture, and enhance the performance of other topical products. Plastic-based exfoliating agents have been used in these formulations for their favorable mechanical properties, but growing environmental concerns over microplastic persistence have accelerated the search for sustainable alternatives, for example, from agro-industrial by-products. Our review examines how Circular Economy principles and upcycling strategies support the development of sustainable exfoliating ingredients, addressing the environmental impact of microplastics and the need for their replacement. Recent studies investigating biobased exfoliating materials obtained from agro-industrial and other biowaste residues, including grape pomace, spent coffee grounds, crabwood bagasse, sinami, apricot shell, Passiflora seeds, and chitin-derived particles, among others, are summarized, highlighting their physicochemical characteristics and dermocosmetic applications as exfoliating ingredients. The principal analytical, biophysical, and clinical methodologies used to evaluate exfoliating efficacy and skin barrier responses were also reviewed. A recurring gap identified across the literature is the frequent absence of direct exfoliation-efficacy assessment, underscoring a persistent methodological challenge for this class of cosmetic compounds. Despite this limitation, the available evidence indicates that sustainable exfoliating particles represent promising, though not yet fully validated, alternatives to conventional plastic microbeads; standardized safety and efficacy testing, together with industrial scale-up studies, remain necessary before their performance can be considered clinically comparable, supporting dermocosmetics that integrate skin performance with the environmentally responsible use of agro-industrial residues.