Documents histopathology 5 results

"Background
A standard short-term inhalation study (STIS) was applied for hazard assessment of 13 metal oxide nanomaterials and micron-scale zinc oxide.
Methods
Rats were exposed to test material aerosols (ranging from 0.5 to 50 mg/m3) for five consecutive days with 14- or 21-day post-exposure observation. Bronchoalveolar lavage fluid (BALF) and histopathological sections of the entire respiratory tract were examined. Pulmonary deposition and clearance and test material translocation into extra-pulmonary organs were assessed.
Results
Inhaled nanomaterials were found in the lung, in alveolar macrophages, and in the draining lymph nodes. Polyacrylate-coated silica was also found in the spleen, and both zinc oxides elicited olfactory epithelium necrosis. None of the other nanomaterials was recorded in extra-pulmonary organs. Eight nanomaterials did not elicit pulmonary effects, and their no observed adverse effect concentrations (NOAECs) were at least 10 mg/m3. Five materials (coated nano-TiO2, both ZnO, both CeO2) evoked concentration-dependent transient pulmonary inflammation. Most effects were at least partially reversible during the post-exposure period. Based on the NOAECs that were derived from quantitative parameters, with BALF polymorphonuclear (PMN) neutrophil counts and total protein concentration being most sensitive, or from the severity of histopathological findings, the materials were ranked by increasing toxic potency into 3 grades: lower toxic potency: BaSO4; SiO2.acrylate (by local NOAEC); SiO2.PEG; SiO2.phosphate; SiO2.amino; nano-ZrO2; ZrO2.TODA; ZrO2.acrylate; medium toxic potency: SiO2.naked; higher toxic potency: coated nano-TiO2; nano-CeO2; Al-doped nano-CeO2; micron-scale ZnO; coated nano-ZnO (and SiO2.acrylate by systemic no observed effect concentration (NOEC)).
Conclusion
The STIS revealed the type of effects of 13 nanomaterials, and micron-scale ZnO, information on their toxic potency, and the location and reversibility of effects. Assessment of lung burden and material translocation provided preliminary biokinetic information. Based upon the study results, the STIS protocol was re-assessed and preliminary suggestions regarding the grouping of nanomaterials for safety assessment were spelled out."

"Les cancers représentent en France la première cause de mortalité chez les hommes et la deuxième cause chez les femmes et figurent parmi les pathologies pouvant être liées à l'environnement. À la demande de l'Afsset, l'Inserm a réuni un groupe d'experts afin d'établir un bilan des connaissances sur les liens entre l'exposition à des facteurs physiques, chimiques ou biologiques présents dans l'atmosphère, l'eau, les sols ou l'alimentation et neuf types de cancers en augmentation au cours des vingt-cinq dernières années : les cancers du poumon, les mésothéliomes, les hémopathies malignes, les tumeurs cérébrales, les cancers du sein, de l'ovaire, du testicule, de la prostate et de la thyroïde. Sont analysés dans cette expertise, les données épidémiologiques sur les différents cancers, les connaissances sur l'exposition aux facteurs environnementaux, les mécanismes de toxicité des polluants, les questions relatives à l'exposition aux faibles doses."

"Defines and describes proposed histological groups for 15 common cancers and gives the appropriate International Classification of Diseases for Oncology (ICD-O) morphology codes. Noting that the characteristics of certain cancers are better defined by a combination of tumour site and morphology, the report responds to the lack of a generally agreed scheme for subdividing cancers at a particular site into histological groups for use in clinical and epidemiological studies. With this need in mind, the report presents groupings of morphology codes for selected cancers in order to facilitate analysis of cancer registry data by histological type and to enable comparisons between datasets from different registries."