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With a growing interest in recreational water quality, there is a need for more affordable methods for detecting fecal indicator organisms, includingEscherichia coli(E. coli). Defined substrate technology (specifically Colilert) is a US Environmental Protection Agency approved method for the detection ofE. coliin beach water, but it requires relatively expensive equipment for enumeration of microbes. The 3M Petrifilm product is not currently approved for analysis of recreational water but has been approved for microbial analysis in the food industry. Both methods are simple to use, but Petrifilm requires less equipment and is less expensive than Colilert and thus has been used as a screening tool by citizens’ groups for enumeration ofE. coliin beach water. In some cases, however, the prescribed incubation at 35 C has been ignored. The objectives of this study were to compareE. coliconcentrations in beach water when enumerated by Colilert (defined substrate) and the PetrifilmE. colitest systems, and to evaluate the effects of incubation temperatures on Petrifilm results. Beach water collected from 20 beaches along lakes Michigan and Superior indicated that 19 beaches had meanE. coliconcentrations orders of magnitude higher when Petrifilm was compared to Colilert (4406 vs. 98 meanE.coli/100 mL). In most cases, use of Petrifilm would result in unnecessary advisories and closures at beaches. Incubation of Petrifilm at 25 or 30 C (below manufacturer's recommendation) required at least 2 days for colony counts to match concentrations enumerated by the recommended method. Overall, the Petrifilm method was not as reliable as currently accepted methods for measurement ofE. coliconcentrations in beach water. [ABSTRACT FROM PUBLISHER]

The article presents a study on the identification of fecal indicator bacteria (FIB) in beach water through predictive modeling in Door County, Wisconsin. It states that an analysis of over four years of Escherichia Coli (E. coli) populations was shown in a geographic gradient to the beaches. It adds that the geographic gradient of E. coli shown means that E. coli concentrations were decreasing while increasing distance from Sturgeon Bay. It also adds that little E. coli variation was represented by the wave length and 48 hour rainfall of predictive models that were developed for beach groups. It notes that low concentration of E. coli in the beaches determines the effectiveness of model results due to the low signal-to-noise ratios and lifted concentrations.

Rainfall and its associated storm water runoff have been associated with transport of many pollutants into beach water. Fecal material, from a variety of animals (humans, pets, livestock, and wildlife), can wash into beach water following rainfall and result in microbial contamination of the beach. Many locales around the world issue pre-emptive beach closures associated with rainfall. This study looked at eight beaches located in Door County,Wisconsin, on Lake Michigan to determine the impact of rainfall on E. coli concentrations in beach water. Water samples were collected from beach water and storm water discharge pipes during rainfall events of 5mm in the previous 24 hours. Six of the eight beaches showed a significant association between rainfall and elevated beach water E. coli concentrations. The duration of the impact of rainfall on beach water E. coli concentrations was variable (immediate to 12 hours). Amount of rainfall in the days previous to the sampling did not have significant impact on the E. coli concentrations measured in beach water. Presence of storm water conveyance pipes adjacent to the beach did not have a uniform impact on beach water E. coli concentrations. This study suggests that each beach needs to be examined on its own with regard to rain impacts on E coli concentrations in beach water. [ABSTRACT FROM AUTHOR]

Objective: The objective of our study was to evaluate the effects of fenoldopam mesylate, a dopamine type 1A receptor agonist and a potent renal vasodilator that markedly increases renal blood flow, on kidney function of patients who were receiving iodinated contrast material for an interventional procedure and thought to be at high risk of contrast-associated nephropathy., Materials and Methods: We retrospectively reviewed the records of all patients who received fenoldopam mesylate to determine the acute and, when possible, the longer term effects on kidney function., Results: Twenty-nine cases were reviewed. The average serum creatinine value before contrast administration was 2.55 mg/dL (range, 1.3-5.8 mg/dL) [corrected]. Twenty-four hours after contrast administration, serum creatinine was measured in 28 of the 29 patients. The serum creatinine values had decreased in 16 of the 28 patients by an average of 0.55 mg/dL [corrected]. In nine patients, the serum creatinine value had not changed. Two of the three increases in the serum creatinine value appear to have been caused primarily by problems that did not involve the contrast material., Conclusion: The use of fenoldopam mesylate at appropriate doses offers patients at high risk for contrast-associated nephropathy a chance to avoid this complication. To learn the extent and true nature of the effect of fenoldopam mesylate in this patient population requires a rigorous scientific trial, which is currently underway.