Montgomery County school officials have suspended a high school teacher who suggested that those of her students who smoke marijuana should attempt to determine whether their supplies of the drug have been tainted by a highly toxic chemical.

The teacher, Andrea Brown, who has taught English literature for seven years at Northwood High School in Silver Spring, was placed on administrative leave without pay on April 3, according to schools spokesman Kenneth R. Muir.

The action was taken after Brown allegedly made available to students in her classes mimeographed copies of the name, address, and phone number of a Palo Alto, Calif., concern that would test samples of marijuana to see if it had been contaminated by the highly toxic herbicide called Paraquat, Muir said.

Such an action would be a potential violation of a school board policy that prohibits teachers from doing anything to "encourage or condone" drug abuse, Muir said.

Gary Howard Simpson, an American Civil Liberties Union attorney who is representing Brown, said that his client had told her students that she did not want to encourage them to smoke (marijuana), but since she knew many of them did, they should be aware of the hazards of Paraquat," Simpson said, paraphrasing Brown.

Brown mentioned in class that she had read a recent Washington Post article quoting federal officials as saying that Paraquat, which has been sprayed on illicit marijuana fields in Mexico by Mexican authorities, can cause the lung damage. Simpson said.

The mimeographed sheets read: "Paraquat Detection: Send 1/2-g (1 j) in a plastic bag and $5 with a five diget (sic) ID number. After 1 or 2 weeks, call and give your number for results." Simpson said.

The sheet then listed the name of the Pharm Chem Research Foundation, in Palo Alto. Calif., and a phone number, Simpson said.

John Kotecki, executive director of Pharm Chem, said it was impossible to say how many samples had been received from Montgomery County, but that thousands of samples were being received each week from around the country requesting the test.

School officials are expected to make a recommendation this week on what permanent action, if any should be taken against Brown.