Investigating Childhood Leukemia in Churchill County, Nevada

BACKGROUND: Sixteen children diagnosed with acute leukemia between 1997 and 2002 lived in Churchill County, Nevada, at the time of or before their illness. Considering the county population and statewide cancer rate, fewer than two cases would be expected. OBJECTIVES: In March 2001, the Centers for Disease Control and Prevention led federal, state, and local agencies in a cross-sectional, case-comparison study to determine if ongoing environmental exposures posed a health risk to residents and to compare levels of contaminants in environmental and biologic samples collected from participating families. METHODS: Surveys with more than 500 variables were administered to 205 people in 69 families. Blood, urine, and cheek cell samples were collected and analyzed for 139 chemicals, eight viral markers, and several genetic polymorphisms. Air, water, soil, and dust samples were collected from almost 80 homes to measure more than 200 chemicals. RESULTS: The scope of this cancer cluster investigation exceeded any previous study of pediatric leukemia. Nonetheless, no exposure consistent with leukemia risk was identified. Overall, tungsten and arsenic levels in urine and water samples were significantly higher than national comparison values; however, levels were similar among case and comparison groups. CONCLUSIONS: Although the cases in this cancer cluster may in fact have a common etiology, their small number and the length of time between diagnosis and our exposure assessment lessen the ability to find an association between leukemia and environmental exposures. Given the limitations of individual cancer cluster investigations, it may prove more efficient to pool laboratory and questionnaire data from similar leukemia clusters

Public Health Investigation After the Discovery of Ricin in a South Carolina Postal Facility

Objectives. In October 2003, a package containing ricin and a note threatening to poison water supplies was discovered in a South Carolina postal facility, becoming the first potential chemical terrorism event involving ricin in the United States. We examined the comprehensive public health investigation that followed and discuss the lessons learned from it. Methods. An investigation consisting primarily of environmental sampling for ricin contamination, performance of health assessments on affected personnel, and local, regional, and national surveillance for ricin-associated illness. Results. Laboratory analysis of 75 environmental sampling specimens revealed no ricin contamination. Health assessments of 36 affected employees were completed. Local surveillance initially identified 3 suspected cases, and national surveillance identified 399 outliers during the 2-week period after the incident. No confirmed cases of ricin-associated illness were identified. Conclusions. A multifaceted and multidisciplinary approach is required for an effective public health response to a chemical threat such as ricin. The results of all of the described activities were used to determine that the facility was safe to reopen and that no public health threat existed

Case-control study of paternal occupation and social class with risk of childhood central nervous system tumours in Great Britain, 1962-2006

Paternal occupational exposures have been proposed as a risk factor for childhood central nervous system (CNS) tumours. This study investigates possible associations between paternal occupational exposure and childhood CNS tumours in Great Britain