The Guardian: skepticism on analytical chemistry about microplastics

Via The Guardian, this fascinating article: 

...Studies claiming to have revealed micro and nanoplastics in the brain, testes, placentas, arteries and elsewhere were reported by media across the world, including the Guardian. There is no doubt that plastic pollution of the natural world is ubiquitous, and present in the food and drink we consume and the air we breathe. But the health damage potentially caused by microplastics and the chemicals they contain is unclear, and an explosion of research has taken off in this area in recent years.

However, micro- and nanoplastic particles are tiny and at the limit of today’s analytical techniques, especially in human tissue. There is no suggestion of malpractice, but researchers told the Guardian of their concern that the race to publish results, in some cases by groups with limited analytical expertise, has led to rushed results and routine scientific checks sometimes being overlooked.

...A key way of measuring the mass of MNPs in a sample is, perhaps counterintuitively, vaporising it, then capturing the fumes. But this method, dubbed Py-GC-MS, has come under particular criticism. “[It] is not currently a suitable technique for identifying polyethylene or PVC due to persistent interferences,” concluded a January 2025 study led by Dr Cassandra Rauert, an environmental chemist at the University of Queensland in Australia.

“I do think it is a problem in the entire field,” Rauert told the Guardian. “I think a lot of the concentrations [of MNPs] that are being reported are completely unrealistic.”

I encourage you to read the whole article and the linked discussions/papers, especially the LinkedIn discussion. 

I have been privately quite skeptical of microplastics studies, especially since they have been mostly (seemingly) reports of 'we saw something, and we think it is plastic.' Nevertheless, this is one of these places where there will be a great argument and hopefully we will have some better science that comes out of the debate.