Final answer:
Salicylic acid, a beta hydroxy acid, is the ingredient with anti-inflammatory and antibacterial properties frequently used in acid peels for acne treatment.
Step-by-step explanation:
The ingredient with anti-inflammatory and antibacterial properties often included in blended acid or designer acid peels is known as salicylic acid. Salicylic acid is a beta hydroxy acid that has a profound impact on skin care, particularly in the treatment of acne. Mild acne treatments frequently contain this ingredient due to its effectiveness in exfoliating the skin and reducing inflammation. It helps to clear pores, reduce swelling and redness, and promote the healing of lesions. On the other hand, retinol is a form of retinoid, which are also used in treating acne due to their ability to reduce inflammation among other mechanisms. Overall, both salicylic acid and retinol play significant roles in acne management, but salicylic acid is the agent known specifically for its presence in acid peels.