> Some of the places I have now read about seem so unlikely (archeological dig, deep bore holes, returning spacecraft)
I think there's good reason to be skeptical of all these results because of contamination. Microplastics are everywhere in a lab from the clothing scientists wear to the sample containers they use to hold everything. The most common consumables like microplates and pipette tips are made out of plastic, covered in plastic, and delivered in plastic.
We went through this same process with DNA in archaeology a few decades ago. Until the equipment was sensitive enough and labs figured out how to properly prepare the samples, they kept coming back with wild conclusions about the stuff they were studying. Stuff like taking live plant matter as controls and then not properly cleaning out equipment before testing the archaeological sample.
It's a hard problem exacerbated by the rush to publish or perish.
I think there's good reason to be skeptical of all these results because of contamination. Microplastics are everywhere in a lab from the clothing scientists wear to the sample containers they use to hold everything. The most common consumables like microplates and pipette tips are made out of plastic, covered in plastic, and delivered in plastic.
We went through this same process with DNA in archaeology a few decades ago. Until the equipment was sensitive enough and labs figured out how to properly prepare the samples, they kept coming back with wild conclusions about the stuff they were studying. Stuff like taking live plant matter as controls and then not properly cleaning out equipment before testing the archaeological sample.
It's a hard problem exacerbated by the rush to publish or perish.