From phthalates to microplastics: Emerging and unresolved biocompatibility risks in extracorporeal circulation

Area of Science:

• Biomaterials Science
• Medical Device Engineering
• Environmental Health

Background:

• Extracorporeal circulation (ECC) devices increasingly use biomaterials with reduced chemical leaching, notably eliminating phthalates like di(2-ethylhexyl) phthalate (DEHP).
• Despite reduced chemical leaching, the generation of microplastic particles during ECC procedures, particularly from manual circuit preparation, is an underrecognized concern.
• The efficacy of current filtration systems in removing these smaller microplastic particles remains largely unknown, raising new biocompatibility questions.

Purpose of the Study:

• To review the emerging evidence on microplastic particle generation during extracorporeal circulation.
• To assess the limitations of current filtration technologies in capturing microplastics.
• To highlight knowledge gaps in ECC biocompatibility concerning particulate contamination.

Main Methods:

• A structured narrative review of literature from PubMed and Web of Science.
• Searches included terms related to phthalates, DEHP-free circuits, microplastics, and extracorporeal circulation.
• Included studies published between 1989 and 2025 focusing on chemical migration, particle release, and biomaterial interactions.

Main Results:

• DEHP-free materials reduce chemical leaching but do not eliminate microplastic generation from mechanical processes like cutting.
• Microplastic contamination in ECC is not systematically quantified, unlike phthalates.
• Current filters are not optimized for sub-micron or small microplastic fractions, leaving potential for particle transit.

Conclusions:

• Microplastic release from manual circuit preparation is an emerging risk in ECC, distinct from chemical leaching.
• Existing filtration may be inadequate for smaller microplastics, necessitating further research.
• Addressing microplastic contamination is crucial for redefining ECC biocompatibility and ensuring patient safety.