You get nice news headlines with no tangible issues to health are found and it's easy to just prove a bunch of microplastics in all the things.
If I wanted an easy PhD I'd likely do the same due to how shitty academic hustle is in today's world...
The White House, taking microplastics seriously: https://www.whitehouse.gov/wp-content/uploads/2024/07/Mobili...
The White House pdf suggests a scientific consensus of some form, stating: “Researchers are sounding alarm bells over the growing presence of microplastics in the human body, and are concerned that the ingestion of microplastics and exposure to plastic-related pollution are posing a growing risk to public health.”