While new state and federal laws are cutting down the number of U.S. meth labs, the deadly drugs continue to flow into the U.S. across the porous border with Mexico, say law enforcement authorities.

The federal anti-meth law was recently amended to permit states to impose their own stiffer restrictions and penalties.

In Oregon, for instance, legislators now require cold medicines containing pseudoephedrine, a principal ingredient in methamphetamine, to be sold only by prescription.

With the passage of these new laws, several state narcotics bureaus have reported the number of meth lab busts to be down by as much as 90 percent over the previous year, according to Jim Kouri of the National Association of Chiefs of Police.

Oklahoma is one of those states. Since April 2004, the first state to ban over-the-counter sales of everyday cold and allergy medicines containing pseudoephedrine has seen a dramatic decrease in the makeshift labs that produced meth.

But at the same time, seizures of smokeable Mexican meth known as “crystal ice” rose nearly fivefold, from 384 cases in the 15 months before the law to 1,875 since.

Mexican cartels have seen the profit potential and filled the vacuum created by the tough new laws in the U.S.

Ice is a very pure, smokable form of methamphetamine that is more addictive than other forms of the substance. Ice is similar in appearance to rock candy, crushed ice, or broken glass. It contains the same active chemical compound as powder methamphetamine, but undergoes a recrystallization process in which some impurities in the methamphetamine are removed. The finished product is allowed to dry into crystal chunks that are broken into rocks for sale.

The Drug Enforcement Administration’s website says that historically, criminal groups from South Korea, Taiwan, or China supplied ice to Hawaii and parts of California, but the availability of Mexican-produced ice has increased abuse in areas of the country that were previously untouched.

Because it metabolizes much slower than cocaine, methamphetamine has longer lasting effects. Agitation, tremors, hypertension, memory loss, hallucinations, psychotic episodes, paranoid delusions, and violent behavior can result from chronic abuse.

“The nation’s prisons and addiction treatment centers have also seen a dramatic increase in what is known as meth mouth, which is the extreme deterioration of dental health because of the damage caused by the chemicals used to make the drug and lack of proper nutrition,” says Kouri. “Withdrawal from high doses of methamphetamine often produces severe depression.”

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