Does high pH indicate an adulterated urine sample?
Urine samples, on standing at room temperature or at elevated temperatures during shipping, may display a gradual increase in pH to around 9. This is normal. A pH of 10 or more is suggestive of adulteration, but, addition of agents to change the pH of the specimen also change the color and appearance of the specimen, and the specimen may have an unusual odor. The laboratory staff are very careful to watch for these signs.
