Drug tests in the first six months of this year showed that less than one-half of 1 percent of airline employees and job applicants in safety and security-related positions used drugs, the Federal Aviation Administration said yesterday.

Of the 120,642 employees and applicants tested, those registering positive for drugs included 18 pilots and other flight deck crew members, 116 flight attendants, 300 maintenance workers, 48 dispatchers, 41 security personnel, five flight instructors and four private air traffic controllers, plus 29 not listed by job function. New job applicants accounted for 345 of the 561 positive test results.

The Air Transport Association, which represents major airlines, said the job applicants were denied employment, and most of the employees were fired or had resigned except for a small number entering rehabilitation programs.

The report is the first major statistical summary of tests ordered last year by the Transportation Department for employees throughout the transportation industry, including airlines, railroads, trucks, buses, the merchant marine and pipelines. The tests are administered at industry expense.

No statistics from the other industries have been released, but the results are likely to put airlines at the bottom of the drug-use list.

"These statistics indicate that drug use in aviation is not widespread, but even one drug user is too many and will not be tolerated," FAA Administrator James B. Busey said in a statement.

"The results . . . indicate the major airlines have far, far less of a drug problem than our society at large, where one in 10 people use illegal drugs, according to government estimates," said Robert J. Aaronson, president of the Air Transport Association.

The Air Line Pilots Association said the results show that the tests were never necessary, and have been imposed on airlines at great cost at a time when they can't afford it.

"The extremely low percentage vindicates what we've been saying all along," said ALPA spokesman John Mazor. "The FAA is obviously using a heavy-handed approach to go after a problem that does not exist to any significant degree."

Under Transportation Department rules, workers involved in security and safety-related positions must be screened for drugs at five levels -- pre-employment, random, periodic, reasonable-cause and post-accident. Some 538,000 employees are subject to the tests, and the relatively low number of people in this sample -- 120,642 -- results from the low test rates allowed during the first year of the new rules.

Of the 216 current employees caught by the tests, 178 were snagged by random tests.

The drug of choice was marijuana -- 346 cases. Next was cocaine with 196 cases. There were 15 amphetamine users, 13 who tested positive for opiates and one who tested positive for PCP. The numbers add up to more than the total number of employees involved because of multiple drug use by some employees.