What are the strengths of this paper (if any)?

Expert 1: I agree with you that the FTIR results proved that the residue contained chemical fingerprints similar to those in the water soluble film. However, these results do not prove that there were microplastics. Microscopes or other imaging techniques are often used to identify microplastics, after which FTIR is  used to determine the type of polymer of the microplastics.  

I agree with expert 4 on the FTIR results. My intention was to indicate that from a technical point of view the FTIR measurement were done properly, although indeed no strong conclusions can be drawn from the results.

In general terms there is agreement on the relevance/importance of the topic of study.

It is very good to see that peer-review works. 5 reviewers (and if SciPinion works experts) come to more or less the same conclusion.
This is obviously not a question to any of the other experts but I am happy to see this.

Expert 5 is raising an interesting point. While I use these pods as well, I actually have never observed sludge in my washing machine nor the pipes. I also just asked around in a friend group and no one has ever observed this.
Maybe the other experts can also comment on this?

I find that there is consensus among our panel that the potential production of microplastics from detergent pods is worth investigating, especially conditions that may favor microplastic formation. But proper context should be acknowledged. The US EPA considers pods to be safe, hence including PVAlc (which likely has some polyvinyl acetate) within its Safer Choice program. Moreover, the PVAlc component of pods was found to be highly water-soluble and biodegradable in aquatic environments under most conditions encountered under washing conditions, which deters the formation of micrplastics, which are water-insoluble. The US FDA has approved PVAlc for use in food packaging, dietary supplements, and pharmaceutical products.  My take is that because of the heavy use of pods, a lot  of PVAlc winds up in wastewater treatment plants (WWTPs; 10,500 metric tons per year per a 2021 study (DOI: 10.3390/ijerph18116027 ) and we must find out the conditions that are amendable to microplastic formation, especially realizing that WWTPs experience a wide variety of materials and conditions.

I am glad to see real consensus around this paper. The comments by experts 1 and 3 really hit the nail on the head, that all 5 reviewers have converged on very similar opinions for most/all aspects of the paper. I am also pleased to notice that everyone agrees that microplastics are indeed concerning and are certainly worth further study, especially considering the massive scale of the quantity of plastics (expert 2), and in particular PVA and PVA variants, that ends up in wastewater. We all agree that the questions initially posed by the authors of the manuscript are good questions.