Abstract A78: Cancer in Hinkley: What was the real problem?

Background: Hinkley, California, is a poor desert community known for a $333 million legal settlement and for the “Erin Brockovich” film that alleged a cancer excess from groundwater contaminated with chromium 6 [Cr(VI)] released by a public utility. The carcinogenic role for aqueous Cr(VI) in humans is disputed.Methods: We assessed observed and expected counts of new cancers, including 19 cancer subtypes in the Hinkley tract for 1996–2008. Indirect standardization yielded expected counts adjusted for age, sex, race/ethnicity, population size, and change in population size. Observed numbers of cancers divided by adjusted expected counts defined standardized incidence ratios (SIR) with 95 percent confidence intervals (CI).Results: After adjusting for demographic characteristics, the observed number of cervix cancers was significantly above the expected count (SIR; 95% CI=2.83; 1.82, 5.86). Findings for all cancers combined (SIR; 95% CI=0.91; 0.78, 1.04) and each of 15 specific cancers did not differ significantly from expected counts. Observed counts for childhood, hematopoietic, and respiratory cancers were slightly above expected counts, while observed counts for digestive and breast cancers were below expected. No nasopharyngeal carcinoma or pancreatic cancers were identified, and the observed prostate cancer count (SIR; 95% CI=0.65; 0.40, 0.98) was significantly below the expected number. The observed count for colorectal cancer was below the expected number, although a markedly larger fraction of Hinkley cases were diagnosed at advanced stage compared to the county, region and state.Conclusions: These findings do not support claims of a generalized cancer excess in Hinkley, although the cervix, prostate, and colorectal cancer findings reveal underutilization of cancer screening in the Hinkley tract. These findings are consistent with previous assessments that did not identify a cancer excess in the Hinkley tract.Funding: The California Department of Public Health, National Cancer Institute (Grant N01-PC-35136 and N01-PC-35139), and Centers for Disease Control and Prevention (Grant N02-PC-54404) funded cancer surveillance necessary for this study.Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):A78.