Why would alchohol not show up on a urine analysis?

Specific urine tests. Have been developed & used; however, none has been completely reliable so far. For example, positive ethyl glucuronide tests can result from use of hand sanitizers, medications, hygiene products, cosmetics, foods, some laundry detergents & other products that contain small levels of alcohol. Blood alcohol levels, breathalyzers, saliva & hair sample tests are more reliable.