BACKGROUND: In 2014, the Kansas Department of Health and Environment became aware of groundwater contamination from tetrachloroethylene and trichloroethylene near and downgradient from the locations of two separate dry cleaning facilities in Wichita, Kansas. One dry cleaning facility was established in 1962 and the other in 1968. The contamination impacted 600 residential properties.
METHODS: KDHE developed an investigation design that entailed: 1) creating a database of the 600 addresses in the area of interest and the current title owners and searching records from the Kansas Cancer Registry (2002-2011) for cases of bladder (including in situ), liver and biliary tree, kidney and renal pelvis, female breast, lung and bronchus, multiple myeloma, and non-Hodgkin’s lymphoma, 2) calculating age-adjusted incidence rates for the area of interest, Sedgwick County, Region 5, and Kansas, 3) calculating the Standardized Incidence Ratio (SIR) for select cancers using incidence rates from the Surveillance, Epidemiology and End Results (SEER) Program to determine the expected number of cases, and 4) searching the Kansas Birth Defects Information System (1985-2015) for any matches between mother’s residential address and the addresses in the area of interest.
RESULTS: Between 2002 and 2011, for the area of interest, the age-adjusted incidence rates of female breast cancer (59.20 cases per 100,000 population, 95% CI: 36.13-82.28), lung and bronchus cancer (29.52 cases per 100,000 population, 95% CI: 16.98-42.07), and all target cancers (79.13 cases per 100,000 population, 95% CI: 59.30-98.97) were statistically significantly lower than the rates for Sedgwick County, Region 5, and Kansas during the same time period. For the area of interest, the observed number of bladder cancer (11 observed cases versus 28.15 expected cases), kidney and renal pelvis (2 observed cases versus 18.43 expected cases), female breast cancer (31 observed versus 80.02 expected), lung and bronchus cancer (34 observed versus 80.75 expected), multiple myeloma (4 observed versus 7.99 expected), and non-Hodgkin’s lymphoma (3 observed versus 24.68 expected) cases were all lower than expected. All Standardized Incidence Ratios were statistically significant. None of the birth defects that were found were associated in the scientific literature with exposure to either tetrachloroethylene or trichloroethylene .
CONCLUSIONS: The rates of all cancers of interest were statistically significantly lower in the area of concern compared to other geographical areas. The number of observed cases of cancers of interest were all statistically significantly lower than the expected number. The evidence did not indicate an unusual number or types of birth defects.