Law enforcement officers busting illegal methamphetamine labs once was a common sight across the United States.
But such raids don't happen as frequently anymore — not since most states and the federal government put severe restrictions on the sale of over-the-counter medications containing pseudoephedrine, the key ingredient in methamphetamine, reports CBS News Correspondent Bill Whitaker.
Drug enforcement agents report the number of meth labs in the U.S. has plummeted.
"Yes, drastically down, in fact," says John Fernandes of the Drug Enforcement Administration. But, he adds, "Unfortunately there is an explosion of meth use."
The epidemic of meth use is still rampant because the drug is still plentiful on America's streets. Why?
"They just came across into Mexico to start production," said Fuillermo Gonzalez of the Tijuana Police Department.
This deadly drug is now a growth industry for Mexico's deadly drug cartels. They're replacing small U.S. kitchen labs with Mexican super labs. The cartels are smuggling ephedrine from China, India and Europe and cooking up huge quantities of cheap meth — including an especially potent variety, Mexican Ice. Then the cartels smuggle it north to U.S. users.
"They're making quite a lot of money off of meth," Gonzalez said. "They are pretty much using the same routes that they've used in the past with cocaine and with marijuana."
By some estimates, as much at 80 percent of the meth on U.S. streets comes from Mexico. Agents see more of it at the border. Meth seizures are up 106 percent in a year at the border crossing near San Diego.
The DEA has joined forces with Mexico to fight meth with a two-pronged strategy.
"Essentially, push the problem south of the border" said the DEA's Fernandes. "And at the same time, the DEA has been able to take a lead with our Mexican counterparts in order to prevent the importations of pseudoephedrine coming into Mexico from other locations, like Hong Kong."
But things look different from south of the border. Mexico now has an exploding meth epidemic of its own.
Mexican authorities have busted 18 meth labs in the city of Tijuana this year alone. One lab was located next door to a day care center.
Police raided the lab after teachers and children reported a sickening chemical smell.
Tijuana now has a growing number of meth addicts seeking help at one of the growing number of rehab centers.
"It's no longer just the drugs passing through Mexico to the United States. We're now consumers," said one Mexican addict.
Users in both nations have created an expanding market for cartel meth — and a growing crisis for law enforcement on both sides of the border.
Copyright 2006 CBS. All rights reserved.