IV. Health Outcome Data Review
In this section, health statistics from communities surrounding Pease AFB were evaluated to identify any elevated rates of cancer. As part of the health assessment process, ATSDR routinely conducts a review of available health data (e.g., birth and death certificates, cancer and birth defects registries) if exposures to site contaminants have occurred, or if there are community concerns regarding specific health outcomes (e.g., cancer, birth defects). This evaluation provides an overview of the general health status of a community, or it may confirm the presence of excess disease or illness in a community.
As part of this Public Health Assessment for Pease AFB, NHDHHS reviewed available information on cancer incidence for the surrounding towns of Newington, Portsmouth, and New Castle. Cancer incidence within Portsmouth and New Castle for the period between 1987 and 1991 (all the data that were available) were not statistically different from the number of cases seen in the State of New Hampshire as a whole during this same period. However, there were two cancer types that were elevated in Portsmouth: non-Hodgkin’s lymphoma among males and cervical cancer among females. Environmental exposures are not thought to be the primary risk factors for the development of these cancer types. There were very few cases observed in Newington during this period which prevented further analysis.
It is important to note that elevated rates of a particular illness in a community may not necessarily be attributed to site contamination, nor does it establish a link or imply causality with environmental contamination identified at a site. Many factors influence the development of disease, including personal lifestyle, occupation, and socioeconomic status. Previously in this document, pathways of exposure to contaminants at Pease Air Force Base were evaluated. Completed exposure pathways were found exclusively for people on the base grounds. Therefore, it is unlikely that the elevated rates of non-Hodgkin’s lymphoma and cervical cancer among males and females in Portsmouth, respectively, were due to chemical contamination on the base. Chemical contamination will not result in adverse health effects without there first being an opportunity for exposure.
Our current understanding of the etiology of cancer is that there can be a delay or latency period of up to decades between exposure to a carcinogen and the onset of the disease. For this public health assessment, NHDHHS reviewed cancer incidence data from the New Hampshire State Cancer Registry for 1987 to 1991, all the data that were available at the time of the evaluation. This period was nearly 15 years after the late 1970s when the highest exposures to TCE in the base water supply likely occurred and, hence, appropriate for evaluating these past exposures. Therefore, while data from the years following 1991 were not reviewed because they were not available at the time, NHDHHS considered the typical latency period of cancer in its evaluation of the available data.
The results and methodology used to evaluate health data for Portsmouth, Newington, and New Castle, New Hampshire, are presented in Appendix D.