Inhalation Toxicology, 16:333, 2004 c Taylor & Francis Inc. Copyright ISSN: 0895-8378 print / 1091-7691 online DOI: 10.1080/08958370490439461 Preface This issue of Inhalation Toxicology is devoted to original peer-reviewed articles related to the non-pulmonary effects of inhaled particulate matter. These articles are a reminder that the respiratory tract is an important portal of entry of air contam- inants that may have effects throughout the body. The articles published here were originally presented as papers in the first International Specialty Conference of the American Associa- tion for Aerosol Research, “Particulate Matter: Atmospheric Sciences, Exposure and the Fourth Colloquium on PM and Human Health,” which was held 31 March–4 April 2003 in Pittsburgh, PA. The conference was cochaired by Drs. Cliff Davidson (Carnegie Mellon U, Pittsburgh, PA), Robert Phalen (UC Irvine, Irvine, CA), and Paul Solomon (U.S. EPA, Las Vegas, NV). One of the primary and successful goals of the conference was to bring together health and exposure scientists with atmospheric scientists, air quality managers, and policymakers to allow for enhanced communications and exchange of information among these groups. These special issues, in Inhalation Toxicology, represent the health- and exposure-related articles submitted for publication from those presented at the conference. At- mospheric sciences-related special journal issues are planned for other journals, including Aerosol Science and Technology (AS&T), Atmospheric Environment (AE), Journal of the Air & Waste Management Association (JAWMA), and the Journal of Geophysical Research (JGR). Nearly 90 papers are planned for publication in 2004 in these journals, along with the papers in Inhalation Toxicology. The conference was primarily sponsored by the U.S. En- vironmental Protection Agency. Other sponsors included the Air and Waste Management Association, American Chem- istry Council, American Petroleum Institute, EPRI, Ford Mo- tor Company, Health Effects Institute, International Society for Aerosols in Medicine, Mid-Atlantic Region Air Management Association, NARSTO, National Institute of Environmental Health Sciences, New York State Energy Research and De- velopment Authority, South Coast Air Quality Management District, Southern Company, U.S. Department of Energy (Of- fice of Fossil Energy, National Energy Technology Laboratory), and University of California Irvine Center for Occupational and Environmental Health. The articles in this issue were all peer reviewed according to Inhalation Toxicology’s standards and revised by authors accordingly. Robert F. Phalen, PhD Guest Editor University of California, Irvine, CA