Developing a method to track oil and gas produced water discharges in estuarine systems using salinity as a conservative tracer.

Produced water is a high salinity by-product resulting from oil and gas production. Disposal methods include surface water discharge from a point source. The current field method used for fate and effect determinations in open water estuarine systems involves extending a compass oriented transect (COT) from the point source discharge--a method designed for a uniform offshore environment that might be inappropriate for the hydrologic and geomorphologic complexities found in estuarine systems. Research was conducted in a canal and a small, semi-enclosed bay to observe effluent behaviour and to determine if salinity could be used to track the effluent. A salinity/conductivity/temperature (SCT) probe measured water properties within 1 cm of the sediment surface and identified a thin, bottom salinity plume that would have gone undetected by conventional instruments. The plume flowed across the sediment surface and towards greater depths. Plume-affected sampling stations exhibited higher levels of sediment contaminant indicators (SCIs) and indicated that station location could affect impact conclusions.

Hepatitis C experience at a community teaching hospital.

BACKGROUND: The purpose of this study was to review the initial serologic testing experience for hepatitis C (HCV) and physician response at a community teaching hospital. METHODS: A retrospective chart review was performed for the 59 (5%) HCV-positive patients of 1244 patients who were tested by means of a new enzyme immunosorbent assay (EIA) for HCV antibodies between October 28, 1990, and October 27, 1991. RESULTS: Physicians identified HCV risk factors, including intravenous drug use (n = 14, 25%) and having received blood products (n = 15, 27%). One half of the patients were not queried about the known risk factors for HCV. The most common reason for ordering an HCV assay was elevated liver enzymes. None of the patients underwent supplementary HCV testing (ie, polymerase chain reaction or recombinant immunoblot assay). In 23 (40%) of the HCV-positive patients, no action was taken by the physician, and 15 (27%) were lost to follow-up. The remaining 18 patients (33%) had further follow-up with laboratory or treatment. CONCLUSIONS: These results indicate the need for increased physician awareness of risk factors for HCV and improved documentation of these factors in taking patient history. In addition, primary care physicians need to be educated about new laboratory tests and how to interpret test results and when to order supplemental testing.