
Working at Toxys as a Study Investigator

Name: Eva de Tombe
Role: Study investigator in investigative toxicology team
With Toxys since: 2023
Background: Bio-Pharmaceutical Sciences
From: The Netherlands
Can you give us a brief description of your role at Toxys?
I am responsible for executing projects that utilize our ToxProfiler assay. From preparing samples, exposing ToxProfiler cells to substances, acquiring images, all the way to analyzing the data, I make sure we produce high-quality results. All of this requires good planning and data management. I also help with writing reports, preparing presentations to inform clients, or with preparing figures for posters to be used at conferences.
What kind of methods, tools and equipment do you regularly use?
In the lab, I use a variety of cell culture techniques. To collect data, I use live cell confocal imaging and automated image segmentation and quantification. Finally, I use RStudio for data analysis and visualization.

What are the roles of other people whom you often collaborate with?
My closest collaboration is with the rest of the investigative toxicology team. With our assistant scientist, we need to be well attuned to each other to efficiently and precisely execute the experiments in the lab. We also sit together with our study director and senior scientist while planning and discussing the results.
What are the most challenging and rewarding things about your work?
The most challenging thing about my work is the fact that we don’t fully know the nature of the substances we receive for testing. For example, the substances could be viscous, volatile, or hard to dissolve. So, I need to treat them with care and be patient while doing so. The most rewarding thing on the other hand is being part of a small team that works closely together. I like that I am responsible for a broad range of tasks and can easily discuss and share ideas in the team.
What is the impact your work has on what a customer receives?
Since our customers receive a report based on experiments, data acquisition, and analyses performed directly by me, my work essentially has a big impact not only on what the customers receive but also on the ultimate decisions they make.

Is there any occasion in your work you can think of that was out of ordinary?
Yes, I can think of different occasions. For example, for a screening project, we needed to test multiple hundreds of substances in a relatively short period of time. Another example was working with a photosensitive substance: I needed to activate it by shining light on it. Last year around Christmas time, it also put a smile on my face to check a substance under the microscope to see precipitations that looked like snowflakes. It felt like a fitting theme.
Tell us about your educational background and previous experiences.
I obtained my bachelor’s and master’s degree in Bio-Pharmaceutical Sciences (Drug Discovery and Safety specialization) at Leiden University. During my thesis internship I investigated the mechanism of bile salt induced apoptosis in cystic fibrosis with mouse cholangiocyte organoids at the Erasmus Medical Centre in Rotterdam. During an earlier internship, I worked on the development of multicolor HepG2 BAC reporter cell lines at the Leiden Academic Centre for Drug Research (LACDR).
When and how did you join Toxys?
I knew about Toxys for a while because during my internship, I used to work with HepG2 BAC reporters that were commercialized by Toxys. So, after completing my master’s, I applied for a vacancy and first joined the genetic toxicology team in 2023. Later, I transferred to my current team.
In your opinion, what is the best thing about working at Toxys?
I am proud to contribute to a work that creates an actual impact in the world. With animal-free methods, we help preventing toxic compounds from reaching the market or we provide mechanistic insights into how they work so more informed decisions can be made.
Finish this sentence: In our team, we always…
…give names to our pipets.
What do you like to do when you are not at work?
I like inline skating, playing on the Switch, and baking.
Learn more!
Would you like to learn more about Eva’s work? Check out our ToxProfiler page or reach out.
If you are interested in joining the team, visit our career page.

