A donor came in for a Federal DOT (department of transportation) test, and, had you walked in behind him, you would have thought we were a marijuana dispensary. We concluded he must have been smoking in his vehicle because the odor was so strong. For reference, marijuana is still federally illegal and DOT employees (truck drivers) are not allowed to use it. We proceeded to start the regulated drug test already very suspicious based on our senses. The donor produced a specimen we would not accept because it had a strong ammonia smell.