Test Shows Lipstick Dye Kills Marijuana Plants : Drugs: U.S. officials consider spraying crops with the cosmetic ingredient. The red color might warn off users.

WASHINGTON — A government test has determined that a red dye used in many lipsticks is a powerful herbicide capable of killing marijuana plants, prompting some Bush Administration officials to propose using the dye in an airborne offensive against domestic marijuana cultivation.

The findings, gleaned from an Agriculture Department experiment on a remote hillside in Hawaii late last year, are also being reviewed to determine if the dye could be used to eliminate marijuana crops in other countries, Administration officials said.

Mexico is considered the most likely setting for an international eradication effort. The Administration reported last week that Mexico produces 10 times more marijuana than was previously known, based on satellite surveillance by the Central Intelligence Agency.

The prospective new weapon, Red Dye No. 22, is regarded by many government experts as safer than conventional herbicides such as paraquat. In addition, its rosy hue would tip off users that their marijuana had been sprayed should the growers choose to market the spoiled crop.

But the use of a commonplace cosmetic dye as a plant killer could cause concern among consumers, who may be somewhat troubled to learn that the same chemical that turns lips an alluring red can cause plants to wither and die.

A Food and Drug Administration official said that the agency knew in 1982, when it approved the dye for use in cosmetic products, that it could be destructive in its pure form, but experts maintain that the chemical loses its toxicity when combined with other ingredients.

The government did not seek permission from federal or state environmental officials before spraying the dye from Drug Enforcement Administration helicopters near Hilo, according to officials involved in the experiment.

But, as the Administration contemplates a possible wider spraying campaign, officials are seeking to determine whether use of the dye on marijuana crops would entail any risk to the environment, sources said.

The experiment is part of a broader Administration attempt to apply new technologies to its anti-drug offensive and--with a doubling of its anti-marijuana budget--to reverse trends that have made the United States an increasingly important producer of the drug.

Although Mexico is believed to produce most of the world’s marijuana, some U.S. officials believe that domestic growers still supply as much as 35% of the marijuana consumed in the United States, in large part because Americans produce the most potent strains of the drug.

In his fiscal 1991 budget, President Bush proposes to spend more than $32 million on marijuana eradication. Top anti-drug officials have recommended that the stepped-up effort include an aerial spraying campaign.

In the past, such proposals have been blocked by public opposition, with critics contending that the spraying could pose environmental hazards and that users could be harmed if they unknowingly smoked marijuana that had been sprayed with paraquat or other herbicides.

But proponents of the red-dye approach argue that the introduction of the new herbicide would resolve those problems, with its distinctive color alone providing an unmistakable warning to the unaware that their marijuana had been sprayed.

In addition, they contend that the dye--which is banned for use in food, but permitted in ingestable cosmetics and drugs--would pose no health risks even if smoked.

The new experimentation with the chemical, known as tetrabromofluoroscein, has been conducted primarily at an Agriculture Department laboratory in Washington. For the field test, drug law enforcement officers in Hawaii used DEA helicopters to douse dozens of illegally planted cannabis plants with red dye sprayed through a 100-foot-long tube.

The plants withered and died in two days, according to officials, who said the dye also appeared to rid the cannabis plants of their psychoactive properties, so that, even if smoked, the marijuana would not produce the desired high.

“The test was effective,” said one Agriculture Department official, who insisted on anonymity. John P. Sutton, chief of the DEA’s cannabis investigations section, said that, after being briefed on the test results, he had no doubt that “this stuff works.”

No public announcement was made of the Hawaii test, and Agriculture Department officials have kept details of the study closely held. Because the size of the test was small--involving between 50 and 100 plants--no notice had to be given to environmental officials, researchers said. Anti-drug officials from other agencies were briefed about the findings early this year.

Since the test, state and federal officials in Hawaii have continued to use the red dye in an aggressive joint spraying campaign against marijuana cultivation, officials said. But, for the time being, they have decided to mix the dye with a commercial product called Rodeo, which contains a proven herbicide called glyphosate.

“It’s not clear whether it’s the dye, the Rodeo, or both,” Bill Paty, chairman of the Hawaii Department of Land and Natural Resources, said in an interview, “but the spraying is working.” He said the dye helped pilots chart where they had sprayed and made it difficult for dealers to sell the tainted marijuana.

Government chemists said the dye, known officially as Drug & Cosmetic Red No. 22, functions as a herbicide because it changes when exposed to light, producing a type of oxygen molecule that inhibits photosynthesis in living plants.

But they said this “photodynamic” process apparently does not take place when the dye is mixed with other ingredients in lipstick and other cosmetics.

Before granting final approval for use of the dye in 1982, the Food and Drug Administration “was well aware of the potential for photodynamic activity, and that was addressed,” an agency official said. “You don’t have women going around with lip problems due to use of these things,” she said.

An FDA chemist, Sandra Bell, said Red Dye No. 22 is used principally as an ingredient in long-wearing lipstick because it leaves a semi-permanent stain. It is a near chemical twin of a more widely used dye, Drug & Cosmetic Red No. 21. The two are described in a Nov. 30, 1982, Federal Register listing as “toxicologically equivalent.”

Most major manufacturers of lipsticks, including Revlon, Max Factor and Maybelline, use Red Dye No. 21 in their products. Red Dye No. 22 is less common, but it is also found in certain kinds of nail polish, according to FDA experts.

Agriculture Department chemists said they are confident that Red Dye No. 22 can be an effective weapon against marijuana, and they are continuing to experiment with it under a high-priority effort funded under the agency’s new $6.5-million anti-drug research budget.

Other top-priority agency projects include studies of the feasibility of deploying a coca-eating caterpillar, the malumbia, as a weapon against cocaine production in South America and of cultivating a fungus, fuceria maxisporum, that is believed to kill marijuana.

Anti-drug officials warned that a potential drawback to use of the red dye against marijuana is that it does not kill plants on contact, as paraquat does, but functions as a herbicide only after being absorbed into the leaves.

But several high-ranking anti-drug officials said they believe the dye eventually would be deployed, in large part because of the internal pressure felt by the Bush Administration to crack down against illicit drug cultivation at home as well as abroad.

The State Department is an active sponsor of aerial spraying programs against marijuana in Mexico and Colombia and is seeking to persuade the governments of Peru and Bolivia to grant approval for a U.S.-backed spraying campaign against coca.

Staff writer Shawn Pogatchnik contributed to this story.