Authorities fear that "cheese" heroin could be making a comeback in some Dallas public schools after two teens died this month from apparent overdoses of the sometimes deadly powder.

In all of 2008, four youths died from suspected cheese overdoses, down from 10 in 2007 and 11 the year before.

The Dallas Independent School District said it remains committed to fighting any resurgence of the mixture of Mexican black tar heroin and ground up cold medicine, although as of late November, the district police no longer had an officer assigned to hunting down heroin.

The change came even as heroin arrests on campuses nearly doubled in the first half of the school year compared with the same period last year, rising from 16 to 26, according to DISD police.

Nearly all the arrests occurred at the same cluster of heavily Hispanic campuses in Dallas where the drug first turned up, in 2005 – Thomas Jefferson, North Dallas and W.T. White high schools.

"As long as heroin is still an issue of the community, we're still going to see it," said DISD spokesman Jon Dahlander. "And we need parents' help, and we need the community's help on this thing. This is a community issue."

Toxicology tests on Sarah Aviles, 17, formerly of Emmett J. Conrad High School, and Marisol Prado, 15, a student at Thomas Jefferson High School, could take weeks.

But authorities believe that cheese killed them.

Both had a history of abusing the drug and had been in treatment.

Dahlander declined to comment on the reassignment of a detective who was investigating cheese cases – including going undercover and networking with federal and state narcotics investigators – saying it was a personnel issue. DISD Police Chief John Blackburn declined to be interviewed for this story.

Dahlander said he did not know whether the officer would be replaced. "I can't really speak to that; I just don't know," he said.

But he noted that heroin arrests are down significantly from two years ago, and he said the current numbers, although rising again, can be seen as both positive and a negative.

"The positive – better enforcement," he said. "The negative – the numbers are going up."

Measures being used to combat cheese on campus include surveillance cameras in schools, drug-sniffing dogs and a voluntary drug testing program, said Suzie Fagg, DISD's executive director of student services.

She said the district also has continued to address the drug issue in community meetings.

Paige Marsh, DISD's director of safe and drug-free schools, said the district recognizes that students are likely to engage in risky behavior during school breaks. In response, she said, the district will make the community aware of activities and clubs available to students during the breaks.

"The more involved and connected they are, the less likely they are to engage in risky behavior," Marsh said.

The two deaths so early in the year, the increase in heroin arrests and the fact that the highly addictive drug still makes up more than 20 percent of all DISD campus drug arrests, even after years of awareness campaigns, is cause for concern, experts said.

"It looks like we're having a resurgence," said Michelle Hemm, program director at Phoenix Academy of Dallas, a residential drug treatment center for children 13 to 17. "All of a sudden, we're getting slammed with kids using cheese."

Another Dallas drug treatment facility, Nexus Recovery Center Inc., has noticed a steady increase in use of cheese by girls.

"It's cheap, it's accessible, and what we're hearing is that most cheese users mix their own concoction," said Abby Foster, director of development and public relations at Nexus.

Toxicology reports from the Dallas County medical examiner's office show that since 2005, at least 30 teens 18 and younger died after ingesting lethal quantities of heroin and diphenhydramine, a common ingredient in nighttime cold medicine.

Authorities say drug dealers, often youths themselves, mix black-tar heroin imported from Mexico with crushed cold tablets. Doses sell for as little as $2, and children as young as 11 have been caught in Dallas schools with the drug.

Both girls who died earlier this month were veterans of treatment programs, and family members say they may have met in rehab.

On Jan. 12, a manager found Sarah dead in a room at the Palomino Motel in the 1300 block of Fort Worth Avenue in West Dallas. She attended Conrad High but had not re-enrolled after leaving in the fall for a treatment center.

Detectives are looking into whom Sarah was with the afternoon before she died, when she told her mother she was meeting a friend.

Two days after Sarah's death, Marisol was found dead at a house in the 7500 block of Mohawk Drive, a few blocks from her home near Love Field.

Police are investigating how the Jefferson High student ended up at the house, where police believe she took cheese heroin and drank alcohol. They have questioned three men, all in their 20s.

Edward Conger, who began as principal at Jefferson this school year, said his campus hasn't eased its efforts to fight cheese use. Parents are still being informed about the drug and students are encouraged to disclose their addictions.

The latest statistics show that eight students have been arrested for heroin possession at Jefferson this school year. There were 21 busts there all last school year, and 29 the year before.

"If there's any kid that's using it, there's a problem, and I'm not going to be happy until there are zero kids," Conger said.

At W.T. White, where eight students have been caught with heroin this year, "We're sending more kids for services because we're proactive about it," said school nurse Nicole Wolf. "Every single case gets reported. We're not going to sweep it under the rug."

The DISD police department has sole responsibility for investigating drug crimes on campuses.

Dallas police Deputy Chief Julian Bernal, who commanded the narcotics unit from 2004 until last month, when he transferred to SWAT commander, said the district should not let its guard down.

"The issue is, to me, you have to have someone working on the problem. If you don't, that's simple math. It will eventually come back," he said.

He said it is imperative that the pipeline of intelligence between DISD police and DPD remains open and robust.

"The communication and work between Dallas police and DISD police was very successful in reducing numbers in schools," Bernal said. "We're working on it from the outside, but it is vitally important they have somebody on the inside providing intelligence and working cases."

Dallas County's Juvenile Department, where DISD students busted with cheese often end up, hasn't seen a change in the number of kids being treated for cheese addiction.

"We have never seen a break in the kids using," said Janet Anselmo-Henson, the department's manager of substance abuse services. "We did see an increase in the female use."

And DISD's arrest statistics, which showed a dramatic drop in heroin cases in late 2007, may be misleading.

"What that said is the kids learned to use [the drug] smarter, learned to hide it better so they couldn't get arrested," she said.

Debbie Meripolski, chair of the Dallas County Cheese/Heroin Task Force and the executive director of the Greater Dallas Council on Drug and Alcohol Abuse, said a steady stream of cheese heroin users has been entering the rehab centers.

"I don't think it ever completely went away," Meripolski said.

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