Results of a survey of Loudoun County youth this spring indicate that fewer students may be smoking cigarettes and marijuana than in the past but that alcohol use has remained essentially unchanged.

The numbers show, too, that drinking and drug use in Loudoun remain on par with national averages -- statistics termed "disconcerting" by one school official.

More than 1,500 students in eighth, 10th and 12th grade were surveyed as part of the "Communities That Care" study, a standardized survey administered nationally by many jurisdictions. In addition to questions about drug use, the survey conducted in Loudoun by the public school system asked students about other "antisocial" behavior, including violence and gang membership. It also provides information about community risk factors that lead students to antisocial behavior and measures that steer them away.

The survey was also administered to Loudoun youth in 1997 and 2001. This time, fewer students reported that they had smoked cigarettes in the last 30 days -- 12.6 percent now compared with 22 percent in 2001. A smaller percentage also said they had used marijuana -- 13.2 percent compared with 20 percent in 2001. This year's number, however, was higher than 1997's 11 percent.

According to the survey, alcohol remains the drug of choice for Loudoun youth. More than 60 percent of those surveyed said they had tried alcohol at least once, and 31.9 percent said they had consumed alcohol in the past 30 days, almost the same as in 2001. Of the 12th-graders surveyed, 77.4 percent said they had tried alcohol and 51.5 percent said they had drunk alcohol at least once in the previous 30 days. A highly regarded national study on the same topic in 2003 showed that 76.6 percent of seniors nationally reported having tried alcohol, and 47.5 percent said they had consumed alcohol in the past 30 days.

Close to 17 percent of Loudoun students said they had consumed five or more drinks in a row in the previous two weeks, behavior researchers call "binge drinking."

"Any level of use is disconcerting, especially so when you look at how many kids by the end of 12th grade report using marijuana and alcohol," said Douglas C. Holmes, Loudoun's assistant superintendent for pupil services. "There are positive things to look at here, but you have too many students using these drugs."

Other statistics showed that 12.2 percent of students surveyed said they had been drunk or high at school in the last year, and 15 percent said they had attacked someone with the intent to harm them in that time period. Six percent of students reported having belonged to a gang with a name.

Carol Kost, chairman of the county's advisory commission on youth, said she was encouraged by the possible decline in tobacco and marijuana use, particularly because there have been preventive efforts in those areas. She said the key to reducing alcohol use is parent education and attention.

Kost said parents must discourage one another from setting a permissive atmosphere by allowing young people to have parties in their homes.

"On the surface, it sounds great to say, 'I'm going to take the keys and watch them so they'll be safe,' " she said. "You turn that around, and you have to say, what are you saying to kids about drinking?"

Kost is also chairman of the Loudoun Youth Initiative, a coalition of county and private groups working to address youth issues. She said the survey data would be combined with the results of student focus groups the initiative conducted during the summer. In November, the initiative will host a forum on youth issues based on the student responses.

The initiative was the brainchild of Supervisor Stephen J. Snow (R-Dulles), who said the study's timing "couldn't be better" in helping the project move forward.

"This gives us a great starting point. . . . This is where we can judge the success of our program," he said.

Snow said Loudoun must pay special attention to the effects of growing communities on children. Compared with students nationally, Loudoun students reported a high degree of personal transitions and mobility in their lives -- one of many risk factors identified by the study. Snow said the frequent moves reminded him of his military career, when he moved his family from base to base.

"There's the disruption of the family -- the new schools, the new friends," he said. "The turmoil for children is tremendous."

Alex Chapple, 17, a senior at Loudoun County High School, said talk of drug and alcohol use among his peers had convinced him that the study's numbers might understate the problem. Chapple, a strong opponent of drug and alcohol use, said he has heard fellow students talk about their use since middle school.

"I know for a fact that everybody talks about it," he said. "And then, where do you draw the line? Are they just talking about it, or are they doing it?"

Copies of the survey are available from Loudoun County public schools.