Quote Originally Posted by dawninthemorning
if it is a dot test, they CANNOT reject on smell.
They sure can, if its an odor thats not supposed to be in human urine (i.e. bleach).

From the DOT website:

Subpart E - Urine Specimen Collections

§ 40.65 What does the collector check for when the employee presents a specimen?

As a collector, you must check the following when the employee gives the collection container to
you:

(c) Signs of tampering. You must inspect the specimen for unusual color, presence of foreign objects or material, or other signs of tampering (e.g., if you notice any unusual odor).

(1) If it is apparent from this inspection that the employee has tampered with the specimen (e.g. blue dye in the specimen, excessive foaming when shaken, smell of bleach), you must immediately conduct a new collection using direct observation procedures (see §40.67 ).

(2) In a case where a specimen is collected under direct observation because of showing signs of tampering, you must process both the original specimen and the specimen collected using direct observation and send the two sets of specimens to the laboratory. This is true even in a case in which the original specimen has insufficient volume but it shows signs of tampering. You must also, as soon as possible, inform the DER and collection site supervisor that a collection took place under direct observation and the reason for doing so.
The rest of the DOT guidelines can be found here:
U.S. Department of Transportation / Office of the Secretary of Transportation