Аннотация:Statement of Retraction We, the Editor and Publisher of Journal of Toxicology and Environmental Health Part A: Current Issues, have retracted the following article: João Fernando Pereira Gomes, João Carlos Moura Bordado, Paula Cristina Silva Albuquerque, "On The Assessment of Exposure to Airborne Ultrafine Particles in Urban Environments," Journal of Toxicology and Environmental Health, Part A: Current Issues, Volume 75, 2012, Pages 1316-1329, 10.1080/15287394.2012.721163 This article was found to be significantly similar to two articles by the same authors, one published in the Journal of the Air and Waste Management Association and one published in Inhalation Toxicology. We have been informed in our decision-making by our policy on publishing ethics and integrity and the COPE guidelines on retractions. The retracted article will remain online to maintain the scholarly record, but it will be digitally watermarked on each page as "Retracted".