Automotive airborne brake wear debris nanoparticles and cytokinesis-block micronucleus assay in peripheral blood lymphocytes: a pilot study

Motor vehicle exhaust and non-exhaust processes play a significant role in environmental pollution, as they are a source of the finest particulate matter. Emissions from non-exhaust processes include wear-products of brakes, tires, automotive hardware, road surface, and traffic signs, but still are paid little attention to. Automotive friction composites for brake pads are composite materials which may consist of potentially hazardous materials and there is a lack of information regarding the potential influence of the brake wear debris (BWD) on the environment, especially on human health. Thus, we focused our study on the genotoxicity of the airborne fraction of BWD using a brake pad model representing an average low-metallic formulation available in the EU market. BWD was generated in the laboratory by a full-scale brake dynamometer and characterized by Raman microspectroscopy, scanning electron microscopy, and transmission electron microscopy showing that it contains nano-sized crystalline metal-based particles. Genotoxicity tested in human lymphocytes in different testing conditions showed an increase in frequencies of micronucleated binucleated cells (MNBNCs) exposed for 48 h to BWD nanoparticles (NPs) (with 10% of foetal calf serum in culture medium) compared with lymphocytes exposed to medium alone, statistically significant only at the concentration 3 µg/cm2 (p=0.032).Web of Science14844944

Association of Inflammatory and Oxidative Status Markers with Metabolic Syndrome and Its Components in 40-to-45-Year-Old Females: A Cross-Sectional Study

Oxidative stress and sterile inflammation play roles in the induction and maintenance of metabolic syndrome (MetS). This study cohort included 170 females aged 40 to 45 years who were categorized according to the presentation of MetS components (e.g., central obesity, insulin resistance, atherogenic dyslipidemia, and elevated systolic blood pressure) as controls not presenting a single component (n = 43), those with pre-MetS displaying one to two components (n = 70), and females manifesting MetS, e.g., ≥3 components (n = 53). We analyzed the trends of seventeen oxidative and nine inflammatory status markers across three clinical categories. A multivariate regression of selected oxidative status and inflammatory markers on the components of MetS was performed. Markers of oxidative damage (malondialdehyde and advanced-glycation-end-products-associated fluorescence of plasma) were similar across the groups. Healthy controls displayed lower uricemia and higher bilirubinemia than females with MetS; and lower leukocyte counts, concentrations of C-reactive protein, interleukine-6, and higher levels of carotenoids/lipids and soluble receptors for advanced glycation end-products than those with pre-MetS and MetS. In multivariate regression models, levels of C-reactive protein, uric acid, and interleukine-6 were consistently associated with MetS components, although the impacts of single markers differed. Our data suggest that a proinflammatory imbalance precedes the manifestation of MetS, while an imbalance of oxidative status accompanies overt MetS. Further studies are needed to elucidate whether determining markers beyond traditional ones could help improve the prognosis of subjects at an early stage of MetS

Toxicity of the airborne brake wear debris

Particulate air pollution from road traffic currently represents significant environmental and health issue. Attention is also paid to the "non-exhaust pollution sources," which includes brake wear debris. During each brake application, the airborne and nonairborne particles are emitted into the environment due to wear. High temperatures and pressures on the friction surfaces initiate chemical and morphological changes of the initial components of brake pads and rotating counterparts. Understanding of impact of matter released from brakes on health is vital. Numerous studies clearly demonstrated that particulate matter caused potential adverse effects related to cytotoxicity, oxidative stress, stimulation of proinflammatory factors, and mutagenicity on the cellular level. This paper compiles our main results in the field of genotoxicity, immunotoxicity, and aquatic toxicity of airborne brake wear particles. The brake wear particles were generated using an automotive brake dynamometer. In vitro human peripheral blood cell model was used for the genotoxicity and immunotoxicity. Assessment of aquatic toxicity was performed on the green algae Raphidocelis subcapitata. Obtained results point to potency of toxicity related to the generated airborne brake wear debris.Web of Science101251

Comprehensive assessment of nephrotoxicity of intravenously administered sodium-oleate-coated ultra-small superparamagnetic iron oxide (USPIO) and titanium dioxide (TiO2) nanoparticles in rats

As a main excretory organ, kidney is predisposed to direct/indirect injury. We addressed the potential nephrotoxic effects following expositions of healthy rats to nanoparticle (NP) loads relevant to humans in a situation of 100% bioavailability. Up to 4 weeks after administration, a single iv bolus of oleate-coated ultra-small superparamagnetic iron oxide NPs (in dose of 0.1%, 1.0% and 10.0% of LD50) or TiO2 NPs (1.0% of LD50) did not elicit decline in renal function, damage to proximal tubules, alterations in: renal histology or expression of pro-inflammatory/ pro-fibrotic genes, markers of systemic or local renal micro-inflammation or oxidative damage. Antioxidant enzyme activities in renal cortex, mildly elevated at 24 h, completely restored at later time points. Data obtained by multifaceted approach enable the prediction of human nephrotoxicity during preclinical studies, and may serve as comparison for alternative testing strategies using in vitro and in silico methods essential for the NP-nephrotoxicity risk assessment