What is referred to as the first line of defense against bacteria when applying eyelash extensions?

Non-broken skin is considered the first line of defense against bacteria during the application of eyelash extensions because it serves as a physical barrier that prevents pathogens from entering the body. The integrity of the skin is crucial; any breaks or cuts can provide an entry point for bacteria, increasing the risk of infection.

While cleansing agents and alcohol are effective in sanitizing and reducing the presence of bacteria on the skin's surface, they do not replace the protective function that intact skin provides. Water, although a cleansing agent to some extent, does not possess the antimicrobial properties necessary to serve as a defense. Therefore, maintaining non-broken skin is essential in preventing potential infections and ensuring a safe application process for eyelash extensions.