Microplastics Discovered in the Reproductive System of Sea Turtles: A Growing Environmental Threat
Scientists from the University of Manchester have made a groundbreaking discovery, identifying significant concentrations of microplastics in the male reproductive system of sea turtles. This alarming finding raises serious concerns about the impact of plastic pollution on marine wildlife, particularly for vulnerable sea turtle populations already facing numerous environmental threats.
Microplastics Detected in Multiple Organs
In addition to the reproductive system, researchers found substantial microplastic contamination in other vital organs of both male and female sea turtles. These included the heart, kidney, liver, spleen, skeletal muscles, subcutaneous fat, stomach, and intestines. The study, published in Marine Environmental Research (2025), highlights the widespread presence of microplastics throughout the turtles’ bodies, suggesting potential long-term health risks.
Study Conducted on Stranded Loggerhead Turtles
The research focused on 10 stranded loggerhead sea turtles recovered by the Oceanogrà fic Foundation of Valencia. These turtles suffered from drowning and exhaustion after being unintentionally caught in commercial fishing nets. The findings provide the first direct evidence that microplastics from ingested materials can translocate to different organs, particularly the reproductive system, potentially impacting their ability to reproduce and sustain their populations.
The Potential Health Impact of Microplastics
The study suggests that microplastics could lead to systemic inflammation and organ damage in sea turtles. Researchers found that the largest microplastic particles, with a median size of 25 microns, were detected in the intestines and fat, while the smallest particles, around 15 microns, were present in the stomach and reproductive organs.
Lead author Leah Costello, a PhD researcher at the University of Manchester, emphasized the severity of the findings, stating:
“Microplastics are a pervasive marine pollutant, comparable to global environmental threats like climate change and ozone depletion. Our study provides the first concrete evidence of microplastic accumulation in the reproductive and other vital organs of loggerhead sea turtles.”
She further noted that even seemingly healthy turtles could be under physiological stress due to microplastic exposure, potentially reducing reproductive success and threatening the stability of recovering populations.
Most Common Microplastic Types Identified
Researchers found that 98.8% of all tissue samples contained foreign microparticles, with approximately 70% being microplastics. The most commonly identified microplastics included:
- Polypropylene (PP) – Found in food packaging, bottle caps, ropes, and fishing gear.
- Polyester fibers – Released from synthetic textiles and personal care products.
- Polyethylene (PE) – The main component of plastic bags, which turtles often mistake for jellyfish.
Additionally, microscopic polyester and cotton fibers were detected in the heart tissue of loggerhead turtles, indicating deep tissue penetration of these pollutants.
The Scale of the Microplastic Pollution Problem
Every year, approximately 3 million tonnes of primary microplastics and 5.3 million tonnes of larger plastic debris enter marine environments. Over time, these plastics degrade into microplastics, further contaminating ecosystems. Scientists speculate that because sea turtles can retain plastics in their gut for up to four months, microplastics may cross biological barriers via the circulatory system, affecting multiple organs and leading to severe health consequences.
Urgent Need for Further Research
Co-author Professor Holly Shiels from the University of Manchester highlighted the potential reproductive and developmental risks associated with microplastic accumulation, stating:
“The buildup of microplastics in sea turtles could result in organ toxicity and reproductive complications, threatening the viability of future generations. More extensive studies are required to fully understand the biological and health impacts of microplastic exposure on sea turtles and other marine species.”
Conclusion
This study underscores the urgent need to address plastic pollution in marine ecosystems. With sea turtle populations already at risk due to habitat destruction, climate change, and human activity, microplastic contamination adds another serious challenge. Protecting marine wildlife from plastic pollution will require global efforts to reduce plastic waste, improve waste management, and support further research into the ecological impacts of microplastics.
Reference:
Costello, L. et al. (2025). “Microplastics Accumulate in All Major Organs of the Mediterranean Loggerhead Sea Turtle (Caretta caretta),” Marine Environmental Research. DOI: 10.1016/j.marenvres.2025.107100.