Inhalation Pathology

EPL has extensive expertise in the evaluation of respiratory tract tissues in animals not only exposed to chemicals and compounds via inhalation, but other routes of exposure as well. EPL has the ability to perform histology and histopathology in accordance with the Good Laboratory Practice guidelines as prescribed by U.S. FDA, U.S. EPA, and OECD.

EPL understands the need for, and the essence of, a variety of exposure models (e.g., nose-only, whole-body, intra-nasal droplets or spray, intra-tracheal, and laryngeal aspiration). At inhalation study necropsies, EPL technical and professional staff ensures that the lungs are instilled with fixative at a constant and uniform pressure, allowing for the appropriate expansion of alveoli and the uncompromised observation of important alveolar structures. Appropriate and uniform methods of histologic preparation of the nose, larynx, and lung are critical for obtaining optimal and appropriate sections to evaluate for treatment-related effects that often occur maximally at specific anatomical sites.

EPL pathologists have performed numerous primary pathologic evaluations on 14-day, 90-day, and chronic inhalation toxicity studies of vapors, aerosols, and particulates for the National Toxicology Program (NTP). EPL’s pathology staff has read and reviewed many high profile studies for a variety of government and commercial clients, and have peer-reviewed and conducted Pathology Working Group (PWG) reviews on several inhalation studies. A sampling of studies evaluated by EPL pathologists include, solvent-refined coal, “old” diesel exhaust, 2007-compliant “new” diesel engine exhaust, coal dust, red phosphorous, 1,3-butadiene, ozone, indium phosphide (and many other particulates), dioxins, formaldehyde, glutaraldehyde, decalin, acrolein, acetaldehyde, nickel compounds, Libby amphibole and amosite asbestos, chlorine, phosphine, synthetic jet fuel, naphthalene, nanofibers, and bleomycin-injury models.

EPL’s pathology staff has published seminal papers on reviews of nasal and laryngeal effects of toxicants. In addition, EPL pathologists have authored and co-authored over 150 papers, abstracts, book chapters, and presentations related to inhalation toxicologic pathology. EPL pathologists were the primary contributors of two CD-ROMs on Respiratory Tract Collection (dogs and rodents). These resources provide a comprehensive summary of the most commonly used methods to prepare the nose, larynx, and lung for pathologic evaluation. These resources are available here.