
A Monash University expert is *available to comment on how high temperatures could be impacting the effectiveness of your sunscreen and other cosmetics, and how you can safeguard them.
Dr Laurence Orlando, Pharmacy and Pharmaceutical Sciences Education, Faculty of Pharmacy and Pharmaceutical Sciences
Contact: +61 450 501 248 (Media Manager Teju Hari Krishna) or media@monash.edu
*Note: Dr Orlando is available only for recorded interviews
- How does high temperature impact different cosmetics?
- How should you store them during summer?
- Can your cosmetics actually "go bad"? And what would happen if you used these cosmetics?
The following can be attributed to Dr Orlando:
“High temperatures can significantly impact both cosmetics and sunscreens, compromising their effectiveness and usability. Chemical sunscreens, which rely on active ingredients like avobenzone and oxybenzone, are particularly heat-sensitive.
“Prolonged exposure to high temperatures—such as inside cars or beach bags—can degrade their UV-filtering abilities, reduce efficacy, and cause physical changes like separation, runniness, or a grainy texture. This instability can lead to uneven application and reduced sun protection, necessitating more frequent reapplication, especially during intense heat or sweating.
“Cosmetics, too, are vulnerable to heat. Creams and lotions may separate, lipsticks and balms can melt, and natural or water-based products may foster bacterial growth. Heat can also oxidize essential oils and active ingredients, altering their scent or causing irritation.
“To prevent these issues, it’s essential to store sunscreens and cosmetics in cool, shaded areas, use insulated bags or ice packs when outdoors, and monitor products for changes in texture, smell, or appearance. It is recommended to use mineral sunscreens, with heat-stable ingredients like zinc oxide or titanium dioxide, as a reliable alternative during extreme heat, as they maintain their stability and provide effective UV protection.”
For any other topics on which you may be seeking expert comment, contact the Monash University Media Unit on +61 3 9903 4840 or media@monash.edu. For more Monash media stories visit our news & events site.