The chemicals used by traffickers in the manufacture of illicit drugs, known as "precursors", are a key element of the clandestine laboratories that are developing in Europe, and a real regulatory and environmental headache for the authorities.
Misappropriation of legal products
“ The emergence of new synthetic products leads to a resurgence "clandestine, makeshift laboratories set up" by low-level traffickers seeking to generate traffic with new products" , summarizes the Anti-Narcotics Office (OFAST) in a note from April 2026.
To do this, they diverting legally sold products and used in the perfume industry or by the chemical or agri-food sectors. Acetic anhydride, for example, used in pharmaceuticals to manufacture aspirin or in industry to produce plastics, is a component of heroin.
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Precursors, "pre-precursors" and chemical engineering
As compounds are identified and placed under international control, new precursors are developed. The increasing use of "pre-precursors" also complicates regulation, notes the French Monitoring Centre for Drugs and Drug Addiction (OFDT). The history of synthetic drug production in Europe is also a history of chemical engineering", summarizes Rita Jorge, of the European Union Drugs Agency (EUDA).
Traffickers adapt recipes and ingredients
This is the case with MDMA, which was long manufactured from sassafras essential oil. When this oil came under regulatory control, traffickers developed alternative recipes. Another possibility is to modify the molecule just enough so that it is no longer subject to control. New measures are being implemented to counter the agility and speed of adaptation of criminal organizations." , notes the OFDT.
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Banning precursor groups?
The solution would be to apply the principle of a generic classification (by groups of precursors) rather than a classification based on names. This measure is the subject of debate within the European Commission. When we talk about drugs in general, we're talking about relatively complex molecules. Applying generic controls to them means saying that anything sharing this complex structure is prohibited." explains Ms. Jorge.
With the forerunners, " We generally talk about smaller, simpler building blocks: those from which everything else is assembled." , THE " smaller Lego from the box" . Gold " if we apply generic legislation to a molecule of this size (…) It is very likely that molecules used to manufacture something other than drugs will be intercepted.“.
Dough, base or salt: " It's all about solubility.
Precursors are involved in the cocaine transformation chain, from coca leaves grown in Peru, Bolivia or Colombia to cocaine hydrochloride (salt) or its concealment by reacting the molecule with a product to make it undetectable.
Initially, the leaves are moistened with limewater or another alkali, then extracted using kerosene. Using sulfuric acid, a neutralized aqueous solution is obtained with lime, causing precipitation. The addition of an oxidant makes the paste more homogeneous. At this stage, it is referred to as "cocaine base."
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Next, there are " optional steps "in the processing of cocaine, which traffickers approach in various ways." Sometimes they re-oxidize and reduce it again, claiming this yields higher-quality cocaine; others don't. It all comes down to solubility." said Ms. Jorge.
Of three of the typical precursors (including atropine), none are listed in the 1988 United Nations Convention against Illicit Traffic in Narcotic Drugs, notes Euda.
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Environmental impact
Another challenge posed by the pioneers is the environmental impact. Once used, they are indeed discharged into wastewater systems or... rivers, sometimes miles from the laboratory to cover their tracks. For every 1 kg of drugs, between 5 and 38 kg of waste are generated. Often, notes the UN, The mixture of chemicals generates substances even more dangerous than each product taken individually.“.
Among French authorities, this concern is becoming ingrained in their thinking. We're at the beginning", commented a gendarme from the Command for the Environment and Health (CesanThe discovery of illegal dumps can help track down criminals, and in the event of a conviction, help cover the cost of restoring the site.
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