Dermal absorption, skin retention and urinary elimination of bisphenol S in rats: in vitro, in vivo and intravenous comparative analysis.

Bisphenol S (BPS) is widely used as a substitute for bisphenol A (BPA) in industrial applications, but concerns have been raised about its dermal absorption and potential systemic toxicity. Here, we investigated the toxicokinetics of BPS following dermal and intravenous (i.v.

Percutaneous absorption of climbazole: In vitro data from human skin.

Climbazole is an antifungal substance used as an active ingredient or antimicrobial preservative in pharmaceuticals and personal care products. It is classified by the EU as an acute toxicant (Category 4), and ECHA has recently confirmed its endocrine disruptor concern. Data on climbazole's skin permeability, and consequently its occupational risks, are limited.

Pulmonary Toxicity of Long, Thick MWCNT and Very Long, Thin Carboxylated MWCNT Aerosols Following 28 Days Whole-Body Exposure.

Pulmonary exposure to carbon nanotubes (CNTs) has been linked to a series of adverse respiratory effects in animal models, including inflammation, genotoxicity, fibrosis, and granuloma formation, the degree and characteristics of which are considered dependent upon the detailed physicochemical properties of the material as inhaled. To further explore the effect of variations in physicochemical properties on pulmonary effects, two different multi-walled CNTs (MWCNTs) were tested in vivo: a pristine MWCNT (pMWCNT) (NM-401) and a surface-modified MWCNT (MWCNT-COOH). Female Sprague-Dawley rats were whole-body exposed for 28 days to MWCNT aerosols (pMWCNT (0.

Percutaneous absorption of two bisphenol a analogues, BPAF and TGSA: Novel In vitro data from human skin.

Bisphenol AF (BPAF) and TGSA are analogues of Bisphenol A (BPA). BPAF is used in polymer synthesis, while TGSA is applied in thermal papers. The EU classifies BPAF as toxic to reproduction and TGSA as a skin sensitizer.

Human in vitro percutaneous absorption of bisphenol S: Assessment of the skin reservoir and occlusion effects.

Bisphenol S (BPS) was introduced in many industrial and commercial applications as a presumed safer alternative to bisphenol A. However, concerns have been raised surrounding skin absorption and potential persistence of BPS and its related toxic effects in humans. A previous study revealed the likelihood of a reservoir building up in exposed skin.

Benchmarking of BMDC assay and related QSAR study for identifying sensitizing chemicals.

The Bone-Marrow derived Dendritic Cell (BMDC) test is a promising assay for identifying sensitizing chemicals based on the 3Rs (Replace, Reduce, Refine) principle. This study expanded the BMDC benchmarking to various in vitro, in chemico, and in silico assays targeting different key events (KE) in the skin sensitization pathway, using common substances datasets. Additionally, a Quantitative Structure-Activity Relationship (QSAR) model was developed to predict the BMDC test outcomes for sensitizing or non-sensitizing chemicals.

Analysis of carbon nanotube levels in organic matter: an inter-laboratory comparison to determine best practice.

Carbon nanotubes (CNTs) are increasingly being used in industrial applications, but their toxicological data in animals and humans are still sparse. To assess the toxicological dose-response of CNTs and to evaluate their pulmonary biopersistence, their quantification in tissues, especially lungs, is crucial. There are currently no reference methods or reference materials for low levels of CNTs in organic matter.

Quantifying Titanium Exposure in Lung Tissues: A Novel Laser-Induced Breakdown Spectroscopy Elemental Imaging-Based Analytical Framework for Biomedical Applications.

Occupational and environmental exposures, particularly those related to urban and suburban atmospheres, are increasingly linked to a range of pulmonary diseases. While diagnostic methods for these diseases are well established, analytical tools for assessing elemental contamination in lung tissue remain underutilized. This study introduces a novel framework based on laser-induced breakdown spectroscopy (LIBS) for the in situ quantification of elemental titanium (Ti) in lung tissues from both animal models and human specimens.

An update of skin permeability data based on a systematic review of recent research.

The cutaneous absorption parameters of xenobiotics are crucial for the development of drugs and cosmetics, as well as for assessing environmental and occupational chemical risks. Despite the great variability in the design of experimental conditions due to uncertain international guidelines, datasets like HuskinDB have been created to report skin absorption endpoints. This review updates available skin permeability data by rigorously compiling research published between 2012 and 2021.

Identification of a Gene Signature Predicting (Nano)Particle-Induced Adverse Lung Outcome in Rats.

Nanoparticles are extensively used in industrial products or as food additives. However, despite their contribution to improving our quality of life, concerns have been raised regarding their potential impact on occupational and public health. To speed up research assessing nanoparticle-related hazards, this study was undertaken to identify early markers of harmful effects on the lungs.

Needlelike, short and thin multi-walled carbon nanotubes: comparison of effects on wild type and p53 rat lungs.

Carbon nanotubes (CNTs) are nanomaterials presenting an occupational inhalation risk during production or handling. The International Agency for Research on Cancer classified one CNT, Mitsui-7 (MWNT-7), as 'possibly carcinogenic to humans'. In recognition of their similarities, a proposal has been submitted to the risk assessment committee of ECHA to classify all fibers with 'Fibre Paradigm' (FP)-compatible dimensions as carcinogenic.

Occupational exposure assessment with solid substances: choosing a vehicle for percutaneous absorption experiments.

Percutaneous occupational exposure to industrial toxicants can be assessed on excised human or animal skins. Numerous factors can significantly influence skin permeation of chemicals and the flux determination. Among them, the vehicle used to solubilize the solid substances is a tricky key step.

Retained particle surface area dose drives inflammation in rat lungs following acute, subacute, and subchronic inhalation of nanomaterials.

Background: An important aspect of nanomaterial (NM) risk assessment is establishing relationships between physicochemical properties and key events governing the toxicological pathway leading to adverse outcomes. The difficulty of NM grouping can be simplified if the most toxicologically relevant dose metric is used to assess the toxicological dose-response. Here, we thoroughly investigated the relationship between acute and chronic inflammation (based on polymorphonuclear neutrophil influx (% PMN) in lung bronchoalveolar lavage) and the retained surface area in the lung.

Exposure to TiO Nanostructured Aerosol Induces Specific Gene Expression Profile Modifications in the Lungs of Young and Elderly Rats.

Although aging is associated with a higher risk of developing respiratory pathologies, very few studies have assessed the impact of age on the adverse effects of inhaled nanoparticles. Using conventional and transcriptomic approaches, this study aimed to compare in young (12-13-week-old) and elderly (19-month-old) fisher F344 rats the pulmonary toxicity of an inhaled nanostructured aerosol of titanium dioxide (TiO). Animals were nose-only exposed to this aerosol at a concentration of 10 mg/m for 6 h per day, 5 days per week for 4 weeks.

Inhaled multi-walled carbon nanotubes differently modulate global gene and protein expression in rat lungs.

Inhalation of multi-walled carbon nanotubes (MWCNTs) induces lung inflammation. Depending on industrial applications, CNTs with different physicochemical characteristics are produced and workers can potentially be exposed. This raises concerns about the long-term health effects of these nanomaterials.

Quantitative measurement of carbon nanotubes in rat lung.

Despite their numerous possible applications, the potential impact of carbon engineered nanomaterials (CEN) on human health, especially after inhalation exposure, is still questioned. Quantification of CEN in the respiratory system is a recurring issue and deposition and pulmonary biopersistence data are essential for toxicological evaluation. In this context, a fully validated standard method for CEN quantification in lung tissue is therefore imperative.

Effects of co-exposure to CS and noise on hearing and balance in rats: continuous versus intermittent CS exposures.

Background: Carbon disulfide (CS) exacerbates the effect of noise on hearing, and disrupts the vestibular system. The goal of this study was to determine whether these effects are also observed with intermittent CS exposure.

Methods: Rats were exposed for 4 weeks (5 days/week, 6 h/day) to a band noise at 106 dB SPL either alone or combined with continuous (63 ppm or 250 ppm) or intermittent (15 min/h or 2 × 15 min/h at 250 ppm) CS.

Human in vitro percutaneous absorption of bisphenol S and bisphenol A: A comparative study.

Bisphenol A (BPA) is widely used in industrial products. Due to the toxicity of this compound, and to comply with restrictions and regulations, manufacturers have progressively replaced it by substitutes. One of the main substitutes used is bisphenol S (BPS).

Intra-erythrocyte chromium as an indicator of exposure to hexavalent chromium: An in vivo evaluation in intravenous administered rat.

Hexavalent chromium (Cr(VI)) compounds are classified as carcinogenic to humans. Whereas chromium measurements in urine and plasma attest to the last few hours of total chromium exposure (all oxidation states of chromium), chromium in red blood cells (RBC) is attributable specifically to Cr(VI) exposure over the last few days. Before recommending Cr in RBC (CrIE) as a biological indicator of Cr(VI) exposure, in vivo studies must be undertaken to assess its reliability.

Proteomic analysis of bronchoalveolar lavage fluid in rat exposed to TiO nanostructured aerosol by inhalation.

The pulmonary toxicological properties of inhaled titanium dioxide were studied using bronchoalveolar lavage fluid (BALF) cytology and proteomics analyses. Fischer 344 rats were exposed to 10 mg/m of TiO nanostructured aerosol by nose-only inhalation for 6 h/day, 5 days/week for 4 weeks. Lung samples were collected up to 180 post-exposure days.

Measuring the middle-ear reflex: A quantitative method to assess effects of industrial solvents on central auditory pathways.

Volatile organic solvents are frequently present in industrial atmospheres. Their lipophilic properties mean they quickly reach the brain following inhalation. Acute exposure to some solvents perturbs the middle ear reflex, which could jeopardize cochlear protection against loud noises.

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Multi-walled carbon nanotubes (MWCNTs), which vary in length, diameter, functionalization and specific surface area, are used in diverse industrial processes. Since these nanomaterials have a high aspect ratio and are biopersistant in the lung, there is a need for a rapid identification of their potential health hazard. We assessed in Sprague-Dawley rats the pulmonary toxicity of two pristine MWCNTs (the "long and thick" NM-401 and the "short and thin" NM-403) following either intratracheal instillation or 4-week inhalation in order to gain insights into the predictability and intercomparability of the two methods.

Short- and long-term gene expression profiles induced by inhaled TiO nanostructured aerosol in rat lung.

The number of workers potentially exposed to nanoparticles (NPs) during industrial processes is increasing, although the toxicological properties of these compounds still need to be fully characterized. As NPs may be aerosolized during industrial processes, inhalation represents their main route of occupational exposure. Here, the short- and long-term pulmonary toxicological properties of titanium dioxide were studied, using conventional and molecular toxicological approaches.

Combined exposure to carbon disulfide and low-frequency noise reversibly affects vestibular function.

Chronic occupational exposure to carbon disulfide (CS2) has debilitating motor and sensory effects in humans, which can increase the risk of falls. Although no mention of vestibulotoxic effects is contained in the literature, epidemiological and experimental data suggest that CS2 could cause low-frequency hearing loss when associated with noise exposure. Low-frequency noise might also perturb the peripheral balance receptor through an as-yet unclear mechanism.

Brain Inflammation, Blood Brain Barrier dysfunction and Neuronal Synaptophysin Decrease after Inhalation Exposure to Titanium Dioxide Nano-aerosol in Aging Rats.

Notwithstanding potential neurotoxicity of inhaled titanium dioxide nanoparticles (TiO NPs), the toxicokinetics and consequences on blood-brain barrier (BBB) function remain poorly characterized. To improve risk assessment, we need to evaluate the impact on BBB under realistic environmental conditions and take into account vulnerability status such as age. 12-13 week and 19-month-old male rats were exposed by inhalation to 10 mg/m of TiO nano-aerosol (6 hrs/day, 5 day/week, for 4 weeks).