Flip any moisturiser jar and you’ll see marketing buzzwords: ‘clean,’ ‘green,’ ‘vegan.’ Yet the very container holding that virtuous cream may be leaching chemicals capable of undoing its benefits. Cosmetic packaging is often an afterthought to consumers, but material scientists consider it an active formulation ingredient because it can migrate into the product, skew stability, and change how the formula reaches your skin. If that container is plastic, three silent problems ride along: chemical leaching, oxidati