Pathology and toxicology findings for search-and-rescue dogs deployed to the September 11, 2001, terrorist attack sites: initial five-year surveillance.

A long-term surveillance study was conducted on 95 search-and-rescue (S&R) dogs deployed to the September 11, 2001, terrorist attack sites; an additional 55 nondeployed S&R dogs served as controls. After 5 years of surveillance, 32% of the deployed dogs have died and 24% of the nondeployed dogs. The mean age at the time of death in these 2 groups of dogs is not significantly different. Causes of death in both groups of dogs include inflammatory, degenerative, and proliferative conditions. No primary pulmonary tumors have been identified to date nor has any significant level of toxicant been found in the tissues from these dogs using assays for general organic compounds and metals or, specifically, for polychlorinated biphenyls. However, significant numbers of both deployed and nondeployed dogs have evidence of inhaled matter as demonstrated by the presence of anthracotic pigments or refractile particulate matter in pulmonary tissue. Although S&R activities in response to the 9/11 terrorist attacks exposed dogs to a wide variety of potentially toxic compounds, to date, these dogs do not appear to suffer from higher mortality or increased pulmonary disease compared with nondeployed dogs. To the authors' knowledge, the current survey represents the first long-term and large-scale survey of the pathology and toxicology of S&R dogs deployed to a major disaster site.