Office of National Drug Control Policy

Controlling Precursor Chemicals

Methamphetamine is often produced using chemicals and other products that are illegally diverted from legitimate sources. Some of the precursor chemicals needed to manufacture meth include pseudoephedrine (contained in over the counter cold medicines), anhydrous ammonia (used primarily as an agricultural fertilizer and industrial refrigerant), and red phosphorus (used in matches).

Some of the common ways used to divert products containing pseudoephedrine include:   

  • “Smurfing” – making multiple purchases at different locations
  • Shelf-Sweeping – the theft of all shelf stock
  • Shoplifting
  • Theft from wholesalers

Illegal drug makers often steal anhydrous ammonia from areas where it is stored and used, such as farms. Attempted thefts have also occurred at such places as refrigeration systems holding ammonia, underground pipelines carrying ammonia, and rail cars transporting anhydrous ammonia. Often thefts are aborted when thieves are injured or overcome by the toxic gas. 

Preventing the theft and diversion of precursor chemicals involves the coordination and cooperation of law enforcement, retailers, farmers, and others who may sell or work with these products. Some methods for preventing retail diversion include setting and enforcing thresholds on the amount of products that can be purchased by customers, storing products behind the retail counter, and establishing education programs for employees. 

Controlling Chemicals and Disrupting Drug Trafficking Operations

With the exception of cannabis, every illicit drug requires chemicals to be refined to its final, consumable form (e.g., the coca plant to cocaine, the poppy plant to heroin, etc.), or is purely the result of chemical synthesis (e.g., methamphetamine, ecstasy, etc).  Keeping these vital chemicals away from drug trafficking organizations is an effective way to prevent or reduce drug production.  However, many of these chemicals are also used for legitimate purposes. Thus, preventing the diversion of these chemicals from legitimate commerce to illicit drug manufacturing is especially challenging. Further, because so many chemicals listed as illicit drug precursors are manufactured all over the world, international cooperation is essential to achieve a lasting impact.

Methamphetamine Production and Chemical Control

Although significant U.S. efforts are made around the world to control the chemicals used for cocaine and heroin production, a major effort has been made to control the chemicals used in methamphetamine production.  This is because of the tremendous risks associated with methamphetamine consumption and production and because, unlike cocaine and heroin, there is no drug crop to eradicate since methamphetamine is a completely synthetic drug.  The chemicals used in methamphetamine production are pseudoephedrine, ephedrine, and pharmaceutical preparations containing these substances (commonly known as "combination products").  Additionally, producers have developed chemicals similar to these products– called analogues – in an effort to evade chemical control laws.

Domestic Methamphetamine Chemical Control

Although it is important to consider the public health benefits of convenient public access to cold medicines such as pseudoephedrine, domestic meth labs pose serious health and safety risks to the public, law enforcement, and children forced to live in or near such toxic environments. Current Federal and most state laws to control pseudoephedrine seek to prevent retail diversion of pseudoephedrine and combination products that contain pseudoephedrine through purchase limits and by keeping the products behind the pharmacy counter, consistent with the Combat Methamphetamine Epidemic Act passed in 2006.  At first, these measures were extremely effective, but meth laboratory incidents are now increasing.  Overall, methamphetamine laboratory incidents nationwide, including labs, dumpsites, and associated equipment, have increased from 6,095 incidents in 2007 to11,239 incidents in 2010.

Drug traffickers are evading these laws and domestically producing methamphetamine in increasing quantities.  “Smurfers,” or teams of pseudoephedrine purchasers, go from store-to-store to evade limits on pseudoephedrine and ephedrine purchases.  Smurfing is feeding not only small neighborhood user labs, but also large-scale “super labs” run by major drug trafficking organizations.

In an effort to address this growing threat, several states – including Alabama, Florida, Hawaii, Illinois, Indiana, Iowa, Kansas, Kentucky, Louisiana, Missouri, Nebraska, Oklahoma, North Carolina, North Dakota, South Carolina, Tennessee, Texas, and Washington – are now using electronic pseudoephedrine sales monitoring systems.  However, those efforts have been unable to prevent a resurgence of small-scale meth production in some states, such as Kentucky and Oklahoma. 

Facing a similar threat, the State of Oregon, in 2006, returned pseudoephedrine to a prescription drug, as it was prior to 1976.  The results have been impressive, with meth lab incidents dropping from 190 in 2005 to 12 in 2010.  In early 2010, Mississippi enacted a similar law, and has also seen encouraging results.  Additional states – such as Alabama, Missouri, Nevada, Oklahoma, and Tennessee – are considering returning to a prescription-only status in order to reduce methamphetamine production within their borders. 

International Controls of Methamphetamine Precursor Chemicals

Global efforts to prevent the diversion of methamphetamine precursors have made significant progress. This is a complex effort, requiring cooperation of the countries that produce these precursor chemicals – principally India, China, and Germany – as well as chemical companies around the world, government regulating and law enforcement agencies and multilateral organizations.  Two international entities have played a crucial role in this effort: the United Nations (U.N.) Commission on Narcotic Drugs (CND) and the International Narcotics Control Board (INCB).  The CND is the central policy-making body within the U.N. system dealing with drug-related matters.  The INCB is a quasi-judicial independent body that monitors the implementation of the three U.N. international drug control conventions.

Building on the passage of a United States-sponsored 2006 CND resolution that requested governments to provide an annual estimate of licit precursor requirements and to track the export and import of such precursors, the United Statescontinues to work with the INCB and other international allies to urge countries to take steps towards implementation of all aspects of this resolution.  This includes requests within the resolution for countries to permit the INCB to share such information with concerned law enforcement and regulatory agencies worldwide.  The INCB Secretariat's program to monitor licit shipments of precursor chemicals through its Pre-Export Notification (PEN) online system has been enhanced by the availability of these national licit estimates.  The data serves as a baseline for authorities in importing and exporting countries, facilitating verification of the chemicals and the quantities proposed in commercial transactions. Authorities can then determine whether importation is warranted – or, if no legitimate commercial use is apparent, whether pending shipments require additional law enforcement scrutiny.  Armed with this information, the INCB can work with the relevant countries to block shipments of chemicals before they are diverted to methamphetamine production.

The international community has taken a number of significant steps in 2010 and 2011 to stop traffickers from getting supplies of precursors to produce methamphetamine.  Specifically, through the recommendations of the United Nations, Members of the UN Commission on Narcotic Drugs voted in favor of the tightening controls on phenylacetic acid, a methamphetamine precursor.  A number of countries also changed their legislation and increased efforts to monitor imports and exports of ephedrine and pseudoephedrine—non-controlled precursor chemicals used to produce methamphetamine.  These changes are yielding impressive results, as demonstrated by Mexico’s July 2011 seizure of over 840 metric tons of precursor chemicals used to produce methamphetamine.

Related Resources:

For more information on precursor chemical control, refer to The Drug Enforcement Administration's Office of Diversion Control combats both the diversion of legal pharmaceuticals to illegal purposes and the diversion of chemicals to use in the production of illegal drugs.

The State Department's International Narcotics Control Strategy Report presents a more detailed global overview of International Chemical Control efforts at:

For more information on the 1988 United Nations Convention against Illicit Traffic in Narcotic Drugs and Psychotropic Substances and list of precursor chemicals frequently used in the illicit manufacture of narcotic drugs and psychotropic substances go to the International Narcotics Control Board website at