The minister's mission has been to get such products out of the hands of Baltimore's youth, who are smoking the stuff in hopes of getting high.
While only a drug lab could determine whether Scooby Snax violates a federal ban on synthetic marijuana, Witherspoon as well as public health and law enforcement officials warn that herbs treated with chemicals designed to mimic the effects of marijuana are too easily obtained in the Baltimore area. Synthetic drugs — often packaged to appeal to young people — can be more dangerous than marijuana.
But federal authorities say the ban is proving hard to enforce. Because Maryland lacks a statute against synthetic marijuana, cases usually must be prosecuted in federal court — by the same system charged with prosecuting high-level drug and conspiracy cases. And federal officials say they have limited resources.
Many gas stations and small neighborhood stores keep the herb products behind the counter. Witherspoon, head of the local chapter of the Southern Christian Leadership Conference, considers a business that sells synthetic marijuana the equivalent of "a drug pusher."
"Because it's synthetic, they're able to make it more powerful," said Mike Gimbel, director of drug education at St. Joseph Medical Center. "The heart rate goes up. There are hallucinations. Even things we don't normally see from regular pot, like violence, we're seeing from synthetic pot."
In July, President Barack Obama signed a broad ban on synthetic marijuana and "bath salts" — synthetic drugs that mimic the effect of cocaine and other stimulants.
While foreign manufacturers are believed to follow certain chemical recipes, buyers can't know for sure whether what's inside a package is mind-altering — and illegal — or merely dried leaves. Law enforcement officers can raid businesses suspected of selling synthetic marijuana, but they cannot bring charges unless chemical testing shows the substances are indeed illegal.
Bath salts have garnered more national attention after reports of users' bizarre behavior — one West Virginia man who police said was high on bath salts is accused of killing a neighbor's pet goat while wearing women's lingerie. But law enforcement and health experts say that synthetic marijuana, which is known as "K2" or "Spice," can pose similar risks.
"I don't know which one is worse, K2 or bath salts." said Carl Kotowski, the assistant agent in charge of the Baltimore office of the U.S. Drug Enforcement Administration. "They have similar effects. The public is very uneducated about the synthetic drug problem. I don't think people realize how dangerous they are."
The drugs, which are also sold on the Internet, are primarily produced in India and China before being shipped to distributors in this country, Kotowski said. He said his agents busted two purveyors of synthetic drugs — one in the city, one in Baltimore County — in July as part of a national sweep, but he added that such efforts are difficult given limited resources.
Witherspoon and his twin brother, Corey Witherspoon, an educator, have been ferreting out stores that sell products they believe to be synthetic marijuana near their Park Heights neighborhood.
They have been reporting to authorities the businesses in which they find suspected synthetic marijuana, and they plan to lobby the Maryland General Assembly next year to pass a state ban on such products.
Corey Witherspoon said the prevalence of the problem came to his attention this year when two students at the alternative school where he works lost consciousness after using synthetic marijuana. One student later confessed that he used the product because it would not be detected in court-ordered drug tests, Witherspoon said.
The brothers recently visited a series of Northwest Baltimore gas stations.
At one major-chain gas station on Reisterstown Road, a cashier fished out a 4-gram package of Scooby Snax from a concealed box and sold it for $10. A lengthy disclaimer on the package says it is a "potpourri product" that is "not for human consumption" and does not contain "any chemical and/or ingredients prohibited by state or federal law."
A few blocks away, at another chain gas station, Corey Witherspoon bought a small vial of dried herbs labeled "Real Live." The package describes the pineapple-flavored product as "smooth & exotic" but "not for human consumption."
"They have it in these exotic flavors to appeal to kids," said Corey Witherspoon.
Attempts to reach the manufacturers of the products were not successful. A website listed on the package of Scooby Snax was no longer functional; no manufacturer was listed on the package of Real Live. Neither package listed the ingredients.
A quick Internet search makes clear that people are using herb products to get high. A series of YouTube videos show teenagers and young adults smoking Scooby Snax while commenting on the sensations it induces.
"This is pretty good [stuff]," says one young teenage boy, inhaling deeply from a bong made out of a plastic water bottle.
"I feel pretty good now. I feel pretty high," said another bleary-eyed young man.
Some commenters on the videos warn their fellow users of serious side effects. "I know people that had strokes. It makes your heart beat real fast," wrote one.
"That stuff gives me panic attacks," wrote another.
Dr. Joshua Sharfstein, Maryland's health secretary, says the availability of synthetic marijuana can lead people to think it is safe.
"Just because something is sold at a gas station does not mean it is safe for kids," Sharfstein said. "Synthetics have been linked to some very serious side effects: catatonia, seizures, hallucinations."
Sharfstein lobbied the state legislature this year to impose a state ban on synthetic marijuana, without success. He lauded the federal ban, which covers not just chemicals known to mimic marijuana, but also their chemical analogs. In the past, manufacturers of such products have responded to more narrowly worded bans by slightly altering chemical formulas.
"It's really easy to evade lists of chemicals because you can just tweak the molecule," Sharfstein said.
Data from Maryland's Poison Control Center show that 159 people contacted the center after using synthetic marijuana from the beginning of the year through mid-August, a slightly higher rate than last year. Four people wound up in critical care units and five in psychiatric facilities after using such products. Eleven others were hospitalized in regular hospital units.
Dr. Bruce Anderson, director of the Poison Control Center at the University of Maryland's School of Pharmacy, noted that the data does not show the number of people who used a drug, only those who contacted the center after being concerned about its effects.
In contrast, 50 people contacted Poison Control about marijuana use during the same period and 50 called about bath salts use.
Kotowski warned that even as authorities try to stamp out synthetic marijuana, manufacturers are likely cooking up new drugs to skirt existing laws — and people will be willing to try them.
"If people were told they could get high taking rat poison, they would take it," he said.