Micro- and nano-plastics (MNPLs) can move along the food chain to higher-level organisms including humans. Three significant routes for MNPLs have been reported: ingestion, inhalation, and dermal contact. Accumulating evidence supports the intestinal toxicity of ingested MNPLs and their role as drivers for increased incidence of colorectal cancer (CRC) in high-risk populations such as inflammatory bowel disease (IBD) patients. However, the mechanisms are largely unknown. In this review, by using the leading scientific publication databases (Web of Science, Google Scholar, Scopus, PubMed, and ScienceDirect), we explored the possible effects and related mechanisms of MNPL exposure on the gut epithelium in healthy conditions and IBD patients. The summarized evidence supports the idea that oral MNPL exposure may contribute to intestinal epithelial damage, thus promoting and sustaining the chronic development of intestinal inflammation, mainly in high-risk populations such as IBD patients. Colonic mucus layer disruption may further facilitate MNPL passage into the bloodstream, thus contributing to the toxic effects of MNPLs on different organ systems and platelet activation, which may, in turn, contribute to the chronic development of inflammation and CRC development. Further exploration of this threat to human health is warranted to reduce potential adverse effects and CRC risk.
微纳米塑料（MNPLs）可通过食物链向包括人类在内的高营养级生物迁移。目前已有三种主要暴露途径被报道：摄入、吸入和皮肤接触。越来越多的证据表明，摄入的MNPLs具有肠道毒性，并可能推动炎症性肠病（IBD）患者等高危人群结直肠癌（CRC）发病率上升，但其作用机制尚不明确。本综述通过检索权威科学文献数据库（Web of Science、Google Scholar、Scopus、PubMed和ScienceDirect），系统探讨了MNPLs暴露对健康人群及IBD患者肠道上皮的潜在影响及相关机制。现有证据表明，口服MNPLs暴露可能导致肠道上皮损伤，从而促进并维持肠道炎症的慢性发展，这在IBD患者等高危人群中尤为显著。结肠黏液层的破坏可能进一步促使MNPLs进入血液循环，进而对多器官系统产生毒性效应并激活血小板，这可能反过来促进炎症慢性化及CRC的发生发展。有必要进一步探究这一人类健康威胁，以降低其潜在不良影响及CRC风险。
肿瘤(癌症)患者之家