In 2021, microplastic experts published the Toxicity of Microplastics Explorer (ToMEx) – an open-access living database on the effects of microplastics on both humans and aquatic organisms. The original database included research published up to the end of 2020. Since then, the number of peer-reviewed publications on the topic has grown exponentially. To maintain the utility of ToMEx for researchers working on microplastic hazard characterization and risk assessment, Leah M. Thornton Hampton from the Southern California Coastal Water Research Project, Costa Mesa, US, and co-authors reported on an update (ToMEx 2.0) in Microplastics and Nanoplastics on September 26, 2025.
Now including data published up to January 11, 2023, and accessible through Web of Science, the database approximately doubled in size; increasing its value for the microplastic research community. However, the authors clarify that for environmental managers, its utility continues to be limited in supporting decision-making “as 89% of studies in ToMEx 2.0 failed to meet minimum screening criteria for threshold derivation, highlighting the need to generate fit-for-purpose toxicity data for threshold development.”
The updated database includes more species (increasing from 109 to 164), more polymer types (from 13 to 21), and a greater diversity of particle morphologies. The trends observed in ToMEx 1.0 mostly remained the same. These include a greater toxicity with smaller particle sizes, a dominance of studies using polystyrene spheres and focusing on fitness/metabolism endpoints, and a lack of dose–response data, which limits the utility for risk assessment. With the increased amount of data, separate ecological health-based microplastic thresholds could be calculated for freshwater and marine organisms for the first time.
The update of ToMEx only became possible through the collective effort of the microplastic research community, which extracted the toxicity data from primary literature and evaluated its quality. The potential of Large Language Model (LLMs) to aid in future data mining was also evaluated through a pilot study.
Reference
Thornton Hampton L., M. P. et al. (2025). “The Toxicity of Microplastics Explorer (ToMEx) 2.0.” Microplastics and Nanoplastics . DOI: 1186/s43591-025-00145-6
This article was originally published by Lisa Zimmermann at the Food Packaging Forum.
