What is the required storage condition for preserving fecal coliform samples?

Fecal coliform samples are sensitive to temperature and environmental conditions, as improper storage can lead to changes in the bacterial population, impacting the accuracy of test results. The correct storage condition is at 4 degrees Celsius in a cooler with ice. This temperature slows bacterial metabolism, stabilizing the microbial population, which is essential for preserving the integrity of the sample until it can be analyzed.

Storing samples at room temperature may result in the growth of bacteria, leading to inaccurate readings of fecal coliform levels. Keeping them beneath direct sunlight can cause temperature fluctuations and further degrade the sample. A standard refrigerator, while it may seem similar to storing the samples on ice, does not ensure that the necessary diminished metabolic activity of the bacteria is maintained as effectively as ice does. Therefore, using ice in a cooler helps to maintain the ideal conditions for the preservation of fecal coliform samples, ensuring reliable testing results.