How should a 24-hour urine specimen be stored during collection?

Storing a 24-hour urine specimen in a refrigerator is essential for maintaining the integrity of the sample during the collection period. This practice helps to prevent the growth of bacteria, degradation of certain chemicals, and changes in the composition of the urine that can occur at room temperature. By refrigerating the specimen, you ensure that analytes remain stable, thus providing accurate results when the specimen is analyzed in the laboratory.

The other storage methods do not offer the same level of protection for the urine specimen. Keeping the specimen at room temperature can lead to alterations in certain components of the urine due to metabolic activity or evaporation. Freezing the specimen may be inappropriate during the collection phase because it could cause the urine to become too concentrated or lead to other changes that may affect test results. Storing the specimen in a dark place, while it may protect it from light-sensitive compounds, does not account for the crucial need for temperature regulation during the collection period. Therefore, refrigeration is the optimal choice for maintaining sample stability.