WASHINGTON - Shortcomings in the oversight of drug testing of commercial drivers is allowing some drivers to work without submitting urine samples for testing, says a new federal report.

The report from the Government Accountability Office, the investigative arm of Congress, said the federal agency responsible for monitoring the safety of commercial drivers, the Federal Motor Carrier Safety Admministration, lacks the resources for oversight and enforcement.

The GAO recommends that the U.S. Secretary of Transportation create a national database of drug testing information and move quickly to improve safety audits.

The GAO also said Congress should pass legislation to ban products that individuals can use to substitute or alter urine samples, require states to suspend commercial driver licenses for individuals who decline to take or fail a drug test, and give the FMCSA more authority over the drug testing process.

Results of the investigation were announced last month by Rep. Jim Oberstar, D-Minn., chairman of the House Transportation Committee, who ordered it in response to an investigation by a Minnesota television that aired in March 2007.

The GAO report said that "although (the Federal Motor Carrier Safety Administration) and its state partners review thousands of carriers each year, these reviews touch about 2 percent of the industry."

At 10 of 24 urine collection sites, the report said, undercover investigators were not asked to empty their pockets, as sites should require, before proving a urine sample.

The report said many factors contribute to the challenges of detecting drivers who are using illegal drugs and keeping them off the road until they complete the required return-to-duty treatment process.

The study also noted that because FMCSA safety audits touch only about 2 percent of all truck and bus companies, carriers have limited incentives to follow the drug testing regulations.

Additionally, drivers have learned that subverting the urine drug tests is easy, either because collection sites are not following protocols or because of the ready availability of products that adulterate or substitute for urine specimens.

For example, GAO investigators, posing as commercial truck drivers needing drug tests, found that employees at 10 of 24 collection sites tested did not ask the investigator to empty his pants pockets, as they are required to do, to ensure he was not carrying adulterants or substitutes.

GAOs analysis identified the following options as having the greatest potential for addressing the issue:

Increasing the number of drivers tested and strengthening the enforcement of safety audits for new carriers. USDOT has begun doing this.

Reducing opportunities to subvert testing and giving FMCSA additional authority to levy fines when collection sites do not follow federal protocols.

Develop a national database of drug testing information.