Epidemiology

Because of the concern of people, a study of mortality has previously been conducted in two Pennsylvania counties located near manufacturing and reprocessing plants of nuclear materials over the period 1950-1995. No excessive mortality has been identified in the population exposed counties in comparison to control counties. The current study is the continuation of the previous study of mortality over a period of eight additional years (up to 2004) and the addition of a study of cancer incidence over the period 1990-2004 and mortality for causes out of cancer from 1996 to 2004. Method: The population of each county of the study was compared to the population of three control counties selected according to socioeconomic and demographic characteristics, the same way as in the previous study. The demographic, mortality and incidence data for the different counties have been earned at the state of Pennsylvania. Results: over the period 1996-2004, mortality from cancer (10 457 deaths) in the two counties studied was comparable to that of six control counties (relative risk .97 [95% CI .94 -. 99]) and previous results. Similarly, the incidence of cancer was similar in the counties studied (39350 cases of cancer) and the control counties (relative risk .99 [95% CI .97-1.00]). The number of deaths unrelated to cancer was 36 565, very close to the expected number (relative risk .99 [95% CI 1.01-1.01]). Conclusion: Overall, no increase in cancer or non-cancer disease could be attributed to living in counties that had manufacturing and reprocessing plants of nuclear materials. (N.C.)