Electron energy loss spectroscopy for analysis of inhaled ultrafine particles in rat lungs

Epidemiologic studies have associated cardiovascular morbidity and mortality with ambient particulate air pollution. Particles smaller than 100 nm in diameter (ultrafine particles) are present in the urban atmosphere in very high numbers yet at very low mass concentration. Organs beyond the lungs are considered as targets for inhaled ultrafine particles, whereby the route of particle translocation deeper into the lungs is unclear. Five rats were exposed to aerosols of ultrafine titanium dioxide particles of a count median diameter of 22 nm (geometric standard deviation, GSD 1.7) for 1 hour. The lungs were fixed by intravascular perfusion of fixatives immediately thereafter. TiO2 particles in probes of the aerosol as well as in systematic tissue samples were analyzed with a LEO 912 transmission electron microscope equipped with an energy filter for elemental microanalysis. The characteristic energy loss spectra were obtained by fast spectrum acquisition. Aerosol particles as well as those in the lung tissue were unambiguously identified by electron energy loss spectroscopy. Particles were mainly found as small clusters with a rounded shape. Seven percent of the particles in the lung tissue had a needle‐like shape. The size distribution of the cluster profiles in the tissue had a count median diameter of 29 nm (GSD 1.7), which indicates no severe clustering or reshaping of the originally inhaled particles. Electron energy loss spectroscopy and related analytical methods were found to be suitable to identify and localize ultrafine titanium dioxide particles within chemically fixed and resin‐embedded lung tissue. Microsc. Res. Tech. 63:298–305, 2004. © 2004 Wiley‐Liss, Inc.

[1]  B. Undem,et al.  Identification and substance P content of vagal afferent neurons innervating the epithelium of the guinea pig trachea. , 1999, American journal of respiratory and critical care medicine.

[2]  W. MacNee,et al.  Particulate air pollution and acute health effects , 1995, The Lancet.

[3]  U. Heinzmann,et al.  Pulmonary and systemic distribution of inhaled ultrafine silver particles in rats. , 2001, Environmental health perspectives.

[4]  S. Schürch,et al.  Surfactant displaces particles toward the epithelium in airways and alveoli. , 1990, Respiration physiology.

[5]  David Brown,et al.  The pulmonary toxicology of ultrafine particles. , 2002, Journal of aerosol medicine : the official journal of the International Society for Aerosols in Medicine.

[6]  Marianne Geiser,et al.  Particle Retention in Airways by Surfactant , 1990 .

[7]  E. Gelsema,et al.  Correspondence Analysis for Quantification in Electron Energy Loss Spectroscopy and Imaging , 1992, Methods of Information in Medicine.

[8]  J. Mauderly,et al.  Deposition and Clearance of Radiolabeled Particles from Small Ciliated Airways in Beagle Dogs , 1989 .

[9]  J. W. Andrew,et al.  High-resolution microanalysis of biological specimens by electron energy loss spectroscopy and by electron spectroscopic imaging. , 1980, Journal of ultrastructure research.

[10]  A. Watson,et al.  Uptake of iron aerosols by mouse airway epithelium. , 1979, Laboratory investigation; a journal of technical methods and pathology.

[11]  J. Heyder,et al.  Techniques for the Determination of Particle Deposition in Lungs of Hamsters , 1989 .

[12]  G. Oberdörster,et al.  Pulmonary retention of ultrafine and fine particles in rats. , 1992, American journal of respiratory cell and molecular biology.

[13]  K. Körtje.  Image‐EELS: Simultaneous recording of multiple electron energy‐loss spectra from series of electron spectroscopic images , 1994 .

[14]  F. Ottensmeyer.  Electron spectroscopic imaging: parallel energy filtering and microanalysis in the fixed-beam electron microscope. , 1984, Journal of ultrastructure research.

[15]  L. Cruz-Orive,et al.  Histological and Stereological Analysis of Particle Retention in the Conducting Airways of Hamster Lungs , 1990 .

[16]  C. Colliex.  Electron Energy‐Loss Spectroscopy Analysis and Imaging of Biological Specimens a , 1986, Annals of the New York Academy of Sciences.

[17]  J. Paulauskis,et al.  Endocytosis of ultrafine particles by A549 cells. , 2001, American journal of respiratory cell and molecular biology.

[18]  Shinji Takenaka,et al.  Generation of Ultrafine Particles by Spark Discharging , 2004 .

[19]  R. Egerton.  Electron Energy-Loss Spectroscopy in the Electron Microscope , 1995, Springer US.

[20]  B. Lehnert,et al.  Correlation Between Particle Size, in Vivo Particle Persistence, and Lung Injury , 1994 .

[21]  C Jeanguillaume,et al.  About the use of electron energy-loss spectroscopy for chemical mapping of thin foils with high spatial resolution. , 1978, Ultramicroscopy.

[22]  A. Schmiedl,et al.  Evaluation of lanthanide tracer methods in the study of mammalian pulmonary parenchyma and cardiac muscle by electron energy‐loss spectroscopy , 1994, Journal of microscopy.

[23]  W. Kreyling,et al.  TRANSLOCATION OF ULTRAFINE INSOLUBLE IRIDIUM PARTICLES FROM LUNG EPITHELIUM TO EXTRAPULMONARY ORGANS IS SIZE DEPENDENT BUT VERY LOW , 2002, Journal of toxicology and environmental health. Part A.

[24]  L. Mortelmans,et al.  Passage of Inhaled Particles Into the Blood Circulation in Humans , 2002, Circulation.

[25]  F. Ottensmeyer.  Scattered electrons in microscopy and microanalysis. , 1982, Science.

[26]  Robert Gelein,et al.  Role of the alveolar macrophage in lung injury: studies with ultrafine particles. , 1992 .

[27]  D. Bodian,et al.  Portals of Entry of Poliomyelitis Virus in the Chimpanzee.∗ , 1940 .

[28]  G. Cournot,et al.  Calcium distribution in high-pressure frozen bone cells by electron energy loss spectroscopy and electron spectroscopic imaging , 1998, Histochemistry and Cell Biology.

[29]  J. Barberà,et al.  Fluticasone propionate attenuates platelet-activating factor-induced gas exchange defects in mild asthma , 2002, European Respiratory Journal.

[30]  P. Taylor,et al.  Major grass pollen allergen Lol p 1 binds to diesel exhaust particles: implications for asthma and air pollution , 1997, Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology.

[31]  A. Peters,et al.  Respiratory effects are associated with the number of ultrafine particles. , 1997, American journal of respiratory and critical care medicine.

[32]  O. Clément,et al.  Distribution of iron oxide nanoparticles in rat lymph nodes studied using electron energy loss spectroscopy (EELS) and electron spectroscopic imaging (ESI) , 2000, Journal of magnetic resonance imaging : JMRI.

[33]  Marianne Geiser,et al.  Influence of surface chemistry and topography of particles on their immersion into the lung's surface-lining layer. , 2003, Journal of applied physiology.