Microplastics and nanoplastics (MNPs) are emerging as a potential risk factor for cardiovascular disease in preclinical studies. Direct evidence that this risk extends to humans is lacking. We conducted a prospective, multicenter, observational study involving patients who were undergoing carotid endarterectomy for asymptomatic carotid artery disease. The excised carotid plaque specimens were analyzed for the presence of MNPs with the use of pyrolysis-gas chromatography-mass spectrometry, stable isotope analysis, and electron microscopy. Inflammatory biomarkers were assessed with enzyme-linked immunosorbent assay and immunohistochemical assay. The primary end point was a composite of myocardial infarction, stroke, or death from any cause among patients who had evidence of MNPs in plaque as compared with patients with plaque that showed no evidence of MNPs. A total of 304 patients were enrolled in the study, and 257 completed a mean (±SD) follow-up of 33.7±6.9 months. Polyethylene was detected in carotid artery plaque of 150 patients (58.4%), with a mean level of 21.7±24.5 μg per milligram of plaque; 31 patients (12.1%) also had measurable amounts of polyvinyl chloride, with a mean level of 5.2±2.4 μg per milligram of plaque. Electron microscopy revealed visible, jagged-edged foreign particles among plaque macrophages and scattered in the external debris. Radiographic examination showed that some of these particles included chlorine. Patients in whom MNPs were detected within the atheroma were at higher risk for a primary end-point event than those in whom these substances were not detected (hazard ratio, 4.53; 95% confidence interval, 2.00 to 10.27; P<0.001). In this study, patients with carotid artery plaque in which MNPs were detected had a higher risk of a composite of myocardial infarction, stroke, or death from any cause at 34 months of follow-up than those in whom MNPs were not detected. (Funded by Programmi di Ricerca Scientifica di Rilevante Interesse Nazionale and others; ClinicalTrials.gov number, NCT05900947.).

Wastewater from livestock farms contains high concentrations of suspended solids, organic contaminants, and nitrogen compounds, such as ammoniacal nitrogen. Discharging livestock effluents into water bodies without appropriate treatment leads to severe environmental pollution. Compared to conventional treatment methods, electrochemical oxidation exhibits higher nitrogen removal efficiencies. In the present work, the electrochemical removal of ammoniacal nitrogen from real livestock wastewater was investigated through a lab-scale reactor. Preliminary experiments were carried out to investigate the effects of different anode materials, including boron-doped diamond and iridium/ruthenium-coated titanium, on the total nitrogen removal efficiency using synthetic wastewater. Boron-doped diamond, a well-known non-active electrode, allowed to obtain 63.7 ± 1.21 % of total nitrogen degradation efficiency. However, the iridium/ruthenium-coated titanium electrode, belonging to the class of active anodes, showed a higher performance, achieving 78.8 ± 0.76 % contaminant degradation. Coupling iridium/ruthenium-coated titanium anode with a stainless-steel cathode improved the performance of the system, achieving even 96.2 ± 2.73 % of total nitrogen removal. The optimized cell configuration was used to treat livestock wastewater, resulting in the degradation of 67.0 ± 2.25 % of total nitrogen and 37.3 ± 0.68 % of total organic carbon when sodium chloride was added. At the end of the process, the ammonium content was completely removed, and only 17.7 ± 0.51 % of the initial nitrogen turned into nitrate. The results show that the proposed system is a promising approach to treating livestock wastewater by coupling high contaminant removal efficiencies with low operational costs. Anyway, further studies on process optimization with an emphasis on power requirements and electrode costs need to be carried out.

Environmental accumulation and human exposure to micro- and nanoplastics (MNPs) are increasing as plastic production rises, yet whether this has been paralleled by greater bioaccumulation in human lungs remains unclear. We conducted a comparative study of paraffin-embedded lung tissues collected post mortem from two series of autopsy cases from the same tertiary care medical center, including individuals who died in 1991 (n = 42) and in 2024 (n = 57). Microplastic abundance, size, and polymer type were assessed using laser-direct infrared (LDIR) imaging. Confirmatory analyses were performed in representative subsets using pyrolysis–gas chromatography/mass spectrometry and scanning electron microscopy. Collagen I staining and CD68 infiltration were evaluated to assess fibrosis and inflammation. MNPs were identified by LDIR in lung samples from 8 of 42 individuals (19%) who died in 1991 and 44 of 57 (77%) who died in 2024. The median MNP burden per gram of tissue (interquartile range) increased from 12.9 particles (11.3–13.7) to 19.9 (15.5–28.2), while mean particle diameter decreased. Polymer composition shifted from polyethylene predominance (51.7%) in 1991 to a more heterogeneous profile in 2024, including polyethylene terephthalate (28.4%), polyvinyl chloride (14.3%), and polystyrene (14.2%), findings corroborated by pyrolysis–gas chromatography/mass spectrometry and scanning electron microscopy. Lung samples containing MNPs showed greater CD68 and collagen I abundance than samples without detectable MNPs. Over the past three decades, MNP contamination of human lung tissue has become markedly more prevalent, compositionally diverse, and characterized by smaller particles, with accompanying histological features consistent with inflammation and fibrosis.