Prevalence and implications of microplastic contaminants in general human seminal fluid: A Raman spectroscopic study.
Level 4 - case-series / case-control
Cross-sectional observational study without an unexposed control group.
PubMed 38802004 · doi:10.1016/j.scitotenv.2024.173522
What was done
Semen samples were collected from 40 men without occupational exposures undergoing premarital health assessments in Jinan, China. Researchers used Raman microspectroscopy to detect, quantify, and identify polymer types of microplastics ranging in size from 0.72 to 7.02 μm. Computer-assisted sperm analysis evaluated motility, Diff-Quik staining assessed morphology, and statistical analyses tested associations between microplastic polymers, demographics, and semen parameters.
What was found
Microplastics were detected in 100% of the 40 semen samples, with an average of 2 particles per sample across eight polymer types. Polystyrene was the most common polymer (31%). Semen containing polystyrene exhibited higher progressive motility compared to semen containing polyvinyl chloride (43.52 ± 14.21% vs 19.04 ± 13.46%). Sperm morphological abnormalities were observed across samples but did not show statistically significant associations with specific polymer types.
Why it matters
This study demonstrates that microplastic exposure is detectable in the seminal fluid of general-population individuals without occupational risk. It suggests that specific plastics, notably polyvinyl chloride, may correlate with reduced sperm progressive motility.
Limits
The sample size was small (40 participants) from a single geographic region. The cross-sectional design cannot establish causality or determine the timing and route of exposure. Particle counts were low (averaging 2 particles per sample), increasing susceptibility to procedural contamination or measurement error. Confounding lifestyle and environmental variables were not fully reported in the abstract.
Cited by
- supports A study of semen samples from 40 healthy young men found microplastics in 100% of samples, averaging 2 particles per sample, with polystyrene accounting for about 31%.
- partial Microplastics in semen, particularly PVC particles, were linked to abnormal sperm shape and impaired motility.