Emily Holt: “Sunscreen is a relatable topic for most people, with finding a reliable option being of high importance. I am asked often what the “best” sunscreen is.” ”

Mathematician-turned-applied-scientist focusses PhD on improving the effectiveness of sunscreens as industry looks to gentler and more environmentally-friendly formulations.

My approach to improving protection offered by sunscreen formulations has been to use advanced laser spectroscopy techniques to study the behaviour of individual sunscreen components upon exposure to ultraviolet (UV) radiation. UV radiation emitted by the sun can, in the worst case, cause skin cancer following prolonged overexposure. Working under the supervision of Prof. Vas Stavros at Warwick and Dr Juan Cebrián at Lubrizol Advanced Materials in Barcelona. my project has had two specific approaches: (i) to understand the light-induced behaviours of current UV filters and (ii) to study new nature-inspired options.

Improvements to sunscreens are needed for several reasons, the first is to reduce the prevalence of allergic reactions to sunscreen formulations, either by reducing the amount of active ingredient within the formulation, or seeking new options that are more compatible with the skin. Moreover, some UV filters are being phased out due to the now well-known detrimental effects to the environment, such as the destruction of coral reefs. Finally, it is very challenging to formulate a sunscreen that offers equal amounts of protection from all wavelengths of UV light.

Sunscreen is a relatable topic for most people, with finding a reliable option being of high importance. I am asked often what the “best” sunscreen is, and what the SPF values and star ratings all mean. I enjoy speaking with people and sharing what I know on this topic, which hopefully helps them to make a more informed choice next time they need to buy a sunscreen product.

During the final year of my maths degree, I decided that I wanted to try a more applied science discipline that made use of the undergraduate knowledge that I gained. I had always had an interest in science throughout my school years but had always overlooked studying them further in favour of maths. The combination of these factors led me to apply for my MSc. During this Masters year, I carried out a 10-week project; it was during this time that I knew that continuing this as a PhD was the right decision for me.

In our group, we tend to allocate weekly blocks of time in the lab, as that suits the nature of our experiments best. On a typical laser lab day, after turning the laser on, we check the optics and alignment of the laser beam are suitable for the wavelength we wish to use. Often the first day of our lab week is ensuring that the conditions are perfect for taking data. In a typical day, we will be able to study one sample in detail. Although, our experiments do not always take place in the laser lab. Other experiments include: using a solar simulator to investigate how the sunscreen ingredients degrade following prolonged exposure to UV radiation; tracking degradation products using a number of analytical techniques; or measuring the fluorescence emitted by a sample. On days when we are not in the lab, there are lots of potential options for work to be done: reading papers, analysing data, writing up results to name a few. Every two weeks, we have a group meeting; one person will present their latest work, then for the remainder of the meeting informal work and lab updates are shared.

During my PhD I have presented at two international cosmetics conferences, one in Munich and the other in Canberra, Australia! As these conferences were industry focused, I gained insights into the research and development that is carried out within cosmetics companies, as well as sales and marketing aspects. I have also had the opportunity to spend a week at the Lubrizol site in Barcelona, during which time I was able to prepare a formulation in their lab and experience other aspects of the business. Also, Lubrizol host a biannual event whereby all their funded PhD students present their work on-site in Derbyshire. These are opportunities that I would not have had without the industry involvement from my PhD. Another highlight has been the 3-day Science Communication course in London, during which we had the opportunity to record a radio show in BBC Broadcasting House.

If you are thinking of a PhD, be sure it is right for you. Spend some time to understand fully what is involved. If you find a supervisor/research project that you like the look of, arrange a meeting with them to discuss it informally. Have a look at the office and lab to see whether the environment is somewhere you would be happy. Perhaps you could meet some members of the group too; ask them about their project and how it has been to work with the supervisor. They will have many experiences to share that might help you to make a more informed choice.

Warwick has been a great place to study for me for the past three years as a postgraduate, in no small part due to playing bassoon and clarinet in the music societies at Warwick. It has been invaluable for me to be able to do the hobby I love whilst completing my PhD.