An unpublished conference abstract presented at the ESHRE 41st Annual Meeting in Paris looks at microplastics in human reproductive fluids.
Prof Oliver Jones, Professor of Chemistry, RMIT University, said:
“It is hard to say much at all about this study without knowing the full details of the methods used and the precautions taken against background contamination. All we have to go on is a very brief abstract, not a peer-reviewed paper. Many previous scary-sounding headlines on microplastics in blood and food have turned out to be measurement errors by people unfamiliar with the problems of microplastic measurements1,2 and/or background contamination3. I don’t think lab contamination can be ruled out in this case. The most common plastic found, PTFE, is very widely used in laboratories, including IVF labs, and background contamination makes all forms of microplastic analysis extremely technically challenging.
“Even if we assume no measurement errors, the results are from a total of 51 individuals, so they are far from conclusive (a limitation acknowledged by the authors), and this study does not claim to demonstrate any harm. We would need these findings to be replicated, ideally in other laboratories around the world, before we could tell if this was a one-off event or not. So, while the data are certainly interesting, they are at best preliminary. I don’t think people who may be trying to conceive, either naturally or via IVF, need to be concerned.”
References
1 Kuhlman, R. L., Letter to the editor, discovery and quantification of plastic particle pollution in human blood. Environment International 2022, 167, 107400, https://www.sciencedirect.com/science/article/pii/S0160412022003270?via%3Dihub
2 Mühlschlegel, P. et al. Lack of evidence for microplastic contamination in honey. Food Additives & Contaminants: Part A 2017, 34 (11), 1982-1989, https://pubmed.ncbi.nlm.nih.gov/28665769/
3 Rauert C. et al. Blueprint for the design construction and validation of a plastic and phthalate-minimised laboratory. Journal of Hazardous Materials 2024 468 133803, https://www.sciencedirect.com/science/article/pii/S0304389424003820
Dr Channa Jayasena, Associate Professor in Reproductive Endocrinology, Imperial College London, said:
“Microplastics are able to interfere with how cells in different bits of the body speak to each other, and can cause cell damage. Unfortunately, it is no longer a surprise that microplastics find their way into the fluids which are essential for men and women to reproduce. This study was very small, and did not report fertility outcomes in the study participants. But it was well-designed study using state-of-the-art technology to show just how commonly microplastics enter reproductive fluids. They showed that most of the studied samples in men and women contained microplastics. Some previous studies have reported that microplastic exposure is associated with lower-than-normal fertility in men. The results contribute to a growing concern for public health – we don’t know what the impact of all types of microplastics are on reproductive function in men and women. Understanding this will help us understand how big a problem microplastics post for fertility in society.”
Dr Stephanie Wright, Associate Professor in Environmental Toxicology, Imperial College London, said:
“Without information on the sizes of the microplastic particles observed, it is challenging to interpret how meaningful this data is. There is a high potential for samples to become contaminated with microplastic throughout the sampling, laboratory processing, and analysis procedures. If stringent steps to minimise this are taken, other clues such as the size of the particles observed can be used to rule out such contamination, with there being a greater likelihood for smaller particles (<0.001 mm > 0.01 mm) being absorbed and redistributed around the body. It is not a surprise that microplastics have been found – they are everywhere, even in the lab – but the data provided do not support that they are there as a result of human exposure as opposed to methodological artefact and must be interpreted with caution at this early stage.”
Prof Fay Couceiro, Professor of Environmental Pollution, and Head of the Microplastics Research Group, University of Portsmouth, said:
“As this is not peer reviewed and there is no detailed methodology it is difficult to give specific information on quality etc. Here are some general comments:
“The study is very interesting and considering the global reduction in fertility rates, looking at possible causes is very topical and timely. As the authors state, finding microplastics is not that surprising as we have found them in lots of other areas of our bodies. Presence is also not the same as impact and the authors are clear that while they have found microplastics in the reproductive fluids of both men and women, we still don’t know how they are affecting us. As a preliminary study the work is interesting, but more information is required on numbers of microplastics found, sizes, method blanks and any plastics used during the medical procedures before any real conclusions can be made. I look forward to reading the full article once it is ready. (A method blank is when you run the experimental steps, but with clean water, and then analyse that to see if you have any microplastics in it. This would let you know if there is any external contamination, and if the microplastics in the samples are from the reproductive fluid, or introduced from the digestion and analysis steps. It would be very unusual not to see any microplastics in the blanks if they are looking below 10 micrometres in size range. At that size, microplastics are in the air and very hard to get away from. If they only analysed larger particles then you tend to find less in your method blanks, but it is common practice to give these in a full paper so that people can see if the number you are finding in your samples is higher than in the blanks.)
Does the press release accurately reflect the science?
“To the extent of which data is available it does, it is clear this is only looking at the presence of microplastics and not impacts.
Is this good quality research? Are the conclusions backed up by solid data?
“Very hard to judge without more in depth information on methods, numbers found in blanks, size ranges of microplastics etc.
Is there enough data available to be able to judge the quality of this work?
“At this stage I would say no – as above the methods really need to be more detailed. Microplastics are everywhere and even with the best methods you find some in the blanks at the smaller sizes (less than 10 um). They say they looked in the containers but the method blank data is missing as are the actual numbers found, e.g. is it 10 microplastics per ml of SF? Is 10 significantly greater than what was found in the method blank? Size range is also very important and not mentioned anywhere I can see.
Is this a peer-reviewed journal publication or more preliminary?
“Preliminary.
How does this work fit with the existing evidence?
“It is expected as microplastics have been found in all bodily fluids/organs tested.
Have the authors accounted for confounders? Are there important limitations to be aware of?
“It is unclear if there is any plastic used in the collection of the samples as I am unfamiliar with the procedures – the storage vessel is glass but is plastic used in the follicular aspiration? Many medical instruments are made from plastic, is that the case here?
What are the implications in the real world? Is there any overspeculation?
“No – they are clear this is just a presence/absence experiment and that further work needs to take place to determine any impacts.”
Abstract title: ‘Unveiling the Hidden Danger: Detection and characterisation of microplastics in human follicular and seminal fluids’ by E. Gomez-Sanchez et al. It will be presented at the ESHRE 41st Annual Meeting in Paris, and the embargo lifted at 23:01 UK time on Tuesday 1 July 2025.
There is no paper.
Declared interests
Prof Oliver Jones: “I am a Professor of Chemistry at RMIT University in Melbourne, Australia. I conduct research into environmental pollution, including microplastics. I have no conflicts of interest to declare.”
Dr Channa Jayasena: “None.”
Dr Stephanie Wright: “Own research: MRC, NERC, NIHR, Common Seas, Minderoo Foundation, LECO;
To attend scientific meetings: American Chemistry Council – to attend a workshop on microplastic reference materials (2022); Minderoo Foundation – to attend workshops on microplastic measurement in human tissue (2024, 2025);
Current or previous advisory roles or committee membership: ILSI Europe, PlasticsEurope (BRIGID project), Cefic LRI projects advisory roles, have been a temporary member of UK Air Quality Expert Group;
Previous employment in companies: none.”
Prof Fay Couceiro: “I work in the field of microplastics but I was not involved in the study and I am not working with the authors. I am unaware of any conflict of interest.”