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Taxation and Customs Union

Drug precursors control

The production of illicit drugs such as heroin, cocaine and amphetamines requires the use of chemicals. These chemicals are called drug precursors.

What are drug precursors?

The production of illicit drugs such as heroin, cocaine and amphetamines requires the use of chemicals. These chemicals are called drug precursors.

A logical way to stop the production of illicit drugs is to prevent illicit drug producers from getting their hands on such drug precursors. This is precisely what drug precursor legislation aims to achieve.

Until some years ago, drug precursors were also legally used to produce legitimate products such as pharmaceuticals, plastics cosmetics, fertilizers and perfumes. That is why drug precursor legislation in the past focused on monitoring legal trade so as to prevent the diversion of drug precursors to illicit drug manufacturing.

However, for the last 5-10 years, illegal drug producers in the European Union are increasingly using so-called ‘designer-precursors’. Designer-precursors are close chemical relatives of traditional drug precursors, are purpose-made to circumvent the controls and usually do not have any known legitimate use.

This presents new challenges for the authorities in the European Union as traditional prevention of diversion is ineffective to address the trafficking of designer-precursors.

Two examples of drug precursors, which have legal use:

  • Acetic anhydride (AA) is used in many industrial processes for the production of plastics, textiles, dyes, photochemical agents, perfumes, explosives and cigarette filters. However, it is also an important reaction agent for the illicit production of heroin. For the production of 1 kg of heroin, 1 to 1.5 litre of AA is required.
  • Ephedrine or pseudo-ephedrine — strong nasal-decongestants — are legally used to manufacture medicinal products against flu or allergies, but they are also key products used in illicit production of methamphetamine. Only 1.5 kg of ephedrine/pseudoephedrine is needed to obtain 1 kg of methamphetamine.

Given the wide range of legitimate uses of drug precursors, their trade cannot be prohibited. Therefore, the legislation aims to strike a balance between the necessary control to prevent diversion of drug precursors and the facilitation of trade (by avoiding creating unnecessary administrative burdens).

An example of drug precursors that has no known legal use:

  • Alpha-phenylacetoacetonitrile (APAAN) is a substance which has no known legal use but it is frequently used in the production of illicit amphetamines.

At the EU level, these substances are "scheduled" (controlled) and they are divided into four categories:

  1. Category 1 covers the most sensitive substances, from which illicit drugs can be produced most easily;
  2. Category 2 covers less sensitive substances
  3. Category 3 covers bulk chemicals that can have different types of uses in the manufacturing process (feedstock, but also solvents, impurity remover, etc.).
  4. Category 4 covers medicinal products for human and veterinary use containing ephedrine or pseudoephedrine.

Who controls them?

In the EU, customs authorities, the police and other departments (health, medicines, internal affairs, etc.) are in charge of drug precursor control. They work in close cooperation with industry.

Article 12 of the 1988 United Nations Convention against Illicit Traffic in Narcotic Drugs and Psychotropic Substances highlights the essential role the industry and the economic operators (e.g. manufacturers, distributors, brokers, importers and exporters, wholesalers and retailers) have to play in combating diversion of drug precursor from legal trade.

These economic operators are the first line of defence against the diversion of drug precursors because they are best placed to know their customers. The purpose of this cooperation, based on a continuous exchange of information, is to facilitate the identification of suspicious transactions and to notify these to the competent authorities. This is compulsory for scheduled substances (categories 1 to 4) and voluntary (but strongly recommended) for non-scheduled substances.

This voluntary cooperation has proven to be effective, offering enough flexibility to quickly respond to changing trends and patterns in the diversion of drug precursors.

Why are they controlled?

Drug precursor policy is a key component of the drug supply reduction policy in the European Union.

Preventing legally traded drug precursors from being diverted into the illegal circuit contributes to the fight against the supply of illegal drugs – as it reduces the amount of available chemicals necessary to make the drugs.

Combating drug precursors' diversion and trafficking is therefore an important objective of the EU Drugs Strategy 2021-2025).

The main features of the current strategy and its first action plan, and how they aim to address Europe’s changing drugs problem, are presented in the analysis of the European Monitoring Center for Drugs and Drug Addiction (EMCDDA).

Further information on the EU drug policy can be found on the website of the European Commission's Directorate General Migration and Home Affairs.

Which legislation applies?

On international level: the UN Convention

The basis for precursor control is the United Nations Convention against Illicit Traffic in Narcotic Drugs and Psychotropic Substances adopted in Vienna on 19 December 1988.

Article 12 of the Convention specifically covers ‘substances frequently used in the illicit manufacture of narcotic drugs and psychotropic substances’ and requires that countries implement measures to control and monitor the legitimate trade in drug precursors as an essential way to prevent their diversion.

On EU level:

The legislation:

The implementation:

In order to implement these Regulations, the Commission can take Delegated Acts:

The evaluation:

On 30 November 2020, the European Commission published an Evaluation of the EU drug precursors regulations.

The European Commission is currently analysing possible options to address the challenges and shortcomings identified in the evaluation.

Practical tools for implementation

The European Commission, in cooperation with EU Member States competent authorities and industry representatives, developed practical tools to support the implementation of the EU legislation on drug precursors.

The list of countries of destination for exports of scheduled substances of Categories 2 and 3

This list contains the name of countries of destination for exports concerned by the controls further to (Article 10 of Commission Delegated Regulation (EU) No 2015/1011 (last update: 10/08/2022).

The EU Guidelines for operators 

The guidelines for operators aim at providing practical guidance for the implementation of the main provisions of the EU legislation on drug precursors. However, given their sensitive nature, they are only distributed by the competent authorities to trusted operators known to them.

The E-learning courses for operators and for customs 

These online courses support the implementation of EU legislation and ensure the dissemination of good practices throughout the European Union.

The courses are used in administrations and businesses as training material and can also be used individually as self-training.

They provide specific information to operators about the methods to identify suspicious transactions and orders at an early stage. They also assist customs officers on how to target suspicious consignments for controls.


25 OCTOBER 2023
Frequently asked questions and answers on the EU rules on drug precursors

International cooperation

Diversion of drug precursors is a global phenomenon, which therefore requires a global response. This is why international cooperation is essential to address the issue.

The UN and the INCB

The 1988 UN Convention against Illicit Traffic in Narcotic Drugs and Psychotropic Substances provides for measures to monitor legitimate trade in precursors to prevent their diversion into the illicit manufacture of drugs.

The International Narcotic Control Board (INCB) is an independent and quasi-judicial monitoring body of the UN in charge of monitoring, among others, the implementation of the 1988 UN Convention. It has also developed useful tools to further international cooperation, namely the Pre-Export Online system (PEN-Online) and the Precursor Incident Communication System (PICS). Further information on the INCB and in particular on the work carried out by its Precursors Control Section can be found on INCB's website.

EU agreements with non-EU countries

Specific bilateral agreements:

In addition to the multilateral framework of the UN 1988 Convention, the EU has established closer cooperation with certain third countries. It has done so by concluding bilateral agreements that seek to prevent drug precursors' diversion through monitoring the licit trade.

At present, the EU has such agreements with 11 countries: Bolivia, Chili, China, Colombia, Ecuador, Mexico, Peru, Russia, Turkey, the United States, and Venezuela.

These agreements provide for cooperation in trade monitoring and mutual administrative assistance (exchange of information). Furthermore, they offer the possibility to exchange information on trends and modus operandi in precursors' diversion and trafficking and to identify adequate solutions in tackling these challenges.

Trade Agreements:

In addition, the EU concludes trade or association Agreements with third countries, containing general provisions on combatting illicit drugs, including the prevention of diversion of drug precursors. These provisions create a legal basis for international cooperation on drug precursors.

Where to find more information?

The annual European Drug Report of the EMCDDA provides information on relevant drug precursor developments including on seizures and stopped shipments by EU Member States' competent authorities.