Characterization of microplastics in human seminal fluid by absorption-reflection infrared spectrometry

Microplastics (MPs) are emerging contaminants that pose a potential risk to both environmental and human health. These polymeric particles, smaller than 5 mm, can be taken up and distributed within the human body, reaching the reproductive system. This study focuses on the detection and characterization of MPs in human seminal fluid using absorption-reflection infrared spectrometry, enabling precise identification of polymer type, morphology, composition, shape and particle size. In addition, statistical studies were performed to explore potential associations between lifestyle habits, semen quality parameters, and MP occurrence in seminal fluid. Samples (1 g) were digested with 2 mL of 10% ( w / v ) KOH at 40 °C for 48 h. In general, a low number of MP particles were detected. Among the identified polymers, polytetrafluoroethylene (PTFE) and polystyrene (PS) were the most frequently observed in some samples. These particles were predominantly rounded and ranged in size from 50 to 100 μm. Statistical evaluation using a permutation analysis of variance was performed, considering the number of particles per gram of sample for the different detected polymers as the response variable, and suggested correlations with certain dietary and hygiene habits. Overall, these findings provide fundamental evidence of low-level MP contamination in the male reproductive system and suggest potential lifestyle-related influences, supporting the need for further research into the implications of MPs for human health.