What does 'pH' measure in skin care products?

The term 'pH' refers to the potential of hydrogen and it measures the acidity or alkalinity of a substance. In the context of skin care products, pH is crucial because it helps determine how the product will interact with the skin. The skin has a natural pH level, typically around 4.5 to 5.5, which means it is slightly acidic. Formulating skin care products with a proper pH level is essential for maintaining the skin's protective barrier and overall health.

When products have a pH that is too high (alkaline) or too low (acidic), they can disrupt the skin’s natural pH balance, potentially leading to irritation, dryness, or other skin issues. For professionals in the cosmetic field, understanding and measuring the pH of products helps ensure their effectiveness and safety when applied to the skin.

The other options do not accurately relate to the scientific meaning of pH. Temperature relates to the warmth of a product, color refers to its visual appearance, and volume pertains to the amount of product available in its packaging. None of these attributes relate to the chemical property that pH measures, which is centered on acidity and alkalinity.