Core Viewpoint - The demand for sunscreen cosmetics is peaking as temperatures rise, but there are concerns about the effectiveness of products claiming to offer multiple benefits, leading to consumer skepticism about product authenticity and safety [1][2]. Group 1: Regulatory Compliance - Sunscreen products must have the "National Cosmetic Special Approval" (国妆特字) number to be legally sold in China, especially those claiming to have sun protection effects [3][4]. - In 2024, the National Medical Products Administration reported that out of 535 batches of cosmetics tested, 120 batches of sunscreen products were found to contain banned ingredients or did not meet regulatory requirements, making up over 22% of all tested cosmetics [2]. Group 2: Consumer Awareness - Consumers are advised to be cautious when selecting sunscreen products, as not all products claiming to have sun protection require the "National Cosmetic Special Approval" number, but those that do must have it if they claim to provide sun protection [4][8]. - Many consumers feel uncertain about how to accurately choose sunscreen products, often relying on sales recommendations without fully understanding product labels [4]. Group 3: Product Identification - Products that claim to have sun protection but lack the "National Cosmetic Special Approval" number or any SPF/PA value labeling are considered non-compliant and potentially misleading [3][7]. - Consumers can verify the legitimacy of sunscreen products by checking for the "National Cosmetic Special Approval" number on the label and using the official cosmetic regulation app to confirm product details [8].

Group 1 - The core viewpoint of the articles emphasizes the importance of proper storage and usage of sunscreen products to maintain their effectiveness, countering the myth that opened sunscreen loses its protective ability even within its expiration date [1][2][3] Group 2 - Sunscreen products can be categorized into two types: those containing physical blockers (like zinc oxide and titanium dioxide) which are stable and maintain effectiveness even after opening, and those with chemical blockers (like avobenzone) which are less stable and require careful storage [1] - Proper storage conditions for sunscreen include avoiding direct sunlight and high temperatures, keeping the product dry and sealed, and minimizing transfer to other containers to prevent contamination [2] - Indicators of sunscreen expiration include visible separation, clumping, discoloration, or unusual odors, and a decrease in effectiveness can be tested by observing skin reactions after application [2][3] Group 3 - Effective application of sunscreen requires using an adequate amount, typically the size of a one-yuan coin for facial coverage, and applying it 15 to 30 minutes before sun exposure [2] - Reapplication is recommended every 2 to 3 hours during prolonged sun exposure to ensure continued protection [2] - Sunscreen should also be applied to all exposed skin areas, and physical barriers like hats and umbrellas can enhance protection [3] - It is important to cleanse the skin of sunscreen after sun exposure, using appropriate cleansing products [3]