Researchers from Leiden University have identified that plastic nanoparticles may interfere with early embryo development, impacting the heart and nervous system. The findings were published in Environment International, highlighting a potential risk that raises concerns about how plastic materials could affect fetal growth in humans and animals alike.
In the study, scientists exposed embryos to elevated levels of polystyrene nanoparticles that are not typically present in the human body. These particles can form when everyday plastics degrade, such as when synthetic fabrics are worn down by ultraviolet light or wind, producing nano- and micro-sized fragments. The investigation used advanced fluorescence imaging to track the movement of these glowing plastic particles after injection, observing their traversal across the intestinal wall of a chick embryo and their distribution through developing organs.
The researchers found that 25-nanometer polystyrene particles adhered to stem cells, hindering their migration to critical regions where the heart, arteries, facial structures, and nervous system normally develop. This disruption of cellular migration can impede normal tissue formation and organ development in the embryo.
Consequences observed in about one quarter of the examined chicken embryos included defects in eye formation, craniofacial abnormalities, thinning of heart muscle, and a slower heartbeat. Neural tube defects were also noted in some cases. Importantly, the severity of these developmental issues rose with higher particle concentrations, suggesting a dose-dependent effect.
Global plastic production reached roughly 360 million tons in 2018, with projections anticipating a substantial rise by the mid-2020s. Prior work indicates microplastics can settle deep within lung tissue, circulate in the bloodstream, and cross the placental barrier, a vital interface that shields unborn babies from maternal pathogens and toxins. These findings underscore the potential for plastic fragments to reach developing fetuses and potentially influence birth outcomes and long-term health. Cited researchers and institutions emphasize the need for further research to quantify exposure risks, understand mechanisms, and determine how real-world levels of environmental plastics may affect human development. In confirming these concerns, the study aligns with broader investigations into how micro- and nanoplastics interact with biological tissues across species, reinforcing the call for cautious management of plastic pollution and exposure, especially among vulnerable populations such as pregnant individuals and growing embryos. The work referenced integrates insights from the Leiden University team and the publishing journal Environment International, reflecting a growing international effort to map the effects of plastic particles on development and health outcomes in Canada, the United States, and beyond.