Groundwater , surface-water, and streambed-sediment samples were collected from domestic, irrigation, and pub Iic supply wells and streams in southeastern Missouri during 1986-87 and analyzed for pesticides, total nitrate, volatile organic compounds, and total recoverable trace elements. Laboratory analyses identified 23 pesticides, nitrate, 3 volatile organic compounds, and 9 trace elements in some of the samples. During the 2-year study 129 sites were sampled. These included 74 domestic wells, 25 irrigation wells, 25 public-supply wells, and 5 stream sites. Of these sites, 26 domestic wells, 4 irrigation wells, 4 public-supply wells, and all 5 stream sites contained water with detectable concentrations of some pesticides, some volatile organic compounds, or some trace elements (including iron and manganese). Total nitrate as nitrogen was detected in 81 of 137 domestic well samples and concentrations in 24 of those samples were equal to or greater than 10 mi 11igrams per liter.

A protocol was developed in 1984 by the Missouri Department of Health to provide a systematic method for responding to citizen reports of cancer clusters. This protocol integrates public health and environmental expertise and includes two stages: the preliminary review and the investigation. The preliminary review is focused on problem definition and hypothesis generation. Cancer mortality and incidence data are reviewed. Information is gathered and verified through the efforts of citizens, local health officials, environmental staff, and the cancer program staff. Epidemlologic factors evaluated include type of cancer, temporal and spatial relations, population at risk, community profile, and possible environmental and occupational factors. The investigation is an expanded analytic study. Resources are focused on cancer inquiries that appear most likely to involve manageable common exposures. Program experience and protocol development highlights, including surveillance system improvement and educational programming, are described.