DAVID MATTINGLY, HOST: Welcome back. High school teachers face a variety of subjects, but in California one instructor also worries about how her students smell.

Anne McDermott explains.

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ANNE MCDERMOTT, CNN CORRESPONDENT (voice-over): This is one kind of assault. This is another. And this one can hurt, too.

JUDITH SANDERSON, TEACHER: It varied from burning my face and nose to being nauseated.

MCDERMOTT: Judith Sanderson is a biology teacher at Culver City High School near Los Angeles. Lots of teenagers wearing lots of perfume and cologne, and that brings on attacks of Sanderson's reactive airways disease.

Dr. Nachman Brautbar is her physician.

DR. NACHMAN BRAUTBAR, SANDERSON'S PHYSICIAN: Patients with reactive airway disease, these tubes narrow down so tightly very little can get into the lungs, the body gets less oxygen, patients feel chest tightness, shortness of breath, headaches, anxiousness, fear, suffocation.

MCDERMOTT: And Sanderson says some assaults by scent are the deliberate work of some of her students. She's counted about 100 such assaults.

SANDERSON: I was just real interested to know how many times somebody was spraying the door and throwing it on the floor, or actually putting it on lab tables.

MCDERMOTT: Most, though, obey Sanderson's edict to go unscented in her classroom. Those who don't are shown the door.

UNIDENTIFIED FEMALE #1: When you're coming in class, she will sniff you. That's from -- I had friends that had her. She will sniff you around, and I mean, you waste a whole period talking about her problem every day.

MCDERMOTT: And it was getting crowded at the principal's office.

MARVIN BROWN, PRINCIPAL: When I became the principal, I felt that the policy was getting out of hand. She was sending too many students up.

MCDERMOTT: The school did give her an air purifier and strengthened her door, but complaints continued, and some thought Sanderson, who developed her disease midway through her teaching career, should quit. Instead, she filed another grievance, and now the school will be installing a camera in her classroom to catch cologne vandals.

Sanderson isn't so sure that's good enough, but concedes, maybe nothing is -- nothing outside a total ban on all assault weapons, including the aromatic kind.

For CNN EARTH MATTERS I'm Anne McDermott.

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