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GROWTH – DEDICATED CALL – 10/99
TOPIC II.11
The use of novel isotopic methodologies to determine the origin of illicit
substances
1. CONFORMITY WITH THE WORK PROGRAMME
This topic is directly related to the R & D activity Fight against Fraud (R & D) under
the Competitive and Sustainable Growth Programme (1.1.3). It falls under the generic
activity 1.1.3-6 Measurement and Testing. Specifically, it is related to that part of the
Objective 1.1.3-6.2 Methodologies for Measurement and Testing for which expressions
of interest have been called.
2. KEYWORDS
Anti-fraud regulations, illegal drugs, stable isotope analysis, NMR, origin assignment.
3. SUMMARY OF OBJECTIVES AND JUSTIFICATION
In the criminal investigation which follows the seizure of illicit drugs, the Customs and
police authorities rely on various physical and chemical evidence of the samples taken
to establish the origin and more particularly the distribution network involved.
Commonly used analytical procedures compare chemical composition obtained mainly
by chromatographic techniques and the judgement is based on the level of impurities or
adulterants in the sample. The results are not always conclusive, particularly when
impurities are only present in trace amount. Work is required to develop methodology,
such as that based on stable isotope ratio analysis, to provide further proof of origin in
difficult cases.
4. BACKGROUND
Each seizure of illicit drugs generally undergoes a thorough physical and chemical
examination to obtain evidence of the probable origin of the drugs for use in the
criminal investigation. Preliminary information can be obtained from a visual inspection
of the product, the nature of packaging used and from questioning the carrier. The
sample is then subject to comparative chemical analyses and the combined information
used to identify the source of the product to establish whether or not products from
different seizures are from a common origin. The latter is especially useful in helping
customs and/or police authorities identify routes of importation and distribution
networks.
Illicit drug samples may differ considerably in their chemical characteristics :
percentage purity, relative concentrations of constituents, presence of adulterants,
diluents, impurities. Chemical fingerprinting (TLC, GC) of an illicit heroin sample can
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provide information of geographical origin based on the relative concentrations of the
principle narcotics diamorphine, 6-acetylmorphine, acetylcodeine, morphine and
codeine. Further evidence can be obtained from the total morphine/papaverine ratio, and
from the relative abundance of main adulterants such as caffeine, procaine,
phenobarbital, and so on.
The main disadvantage of chemical profiling is that it varies with time depending on
storage and transport conditions. To provide further conclusive proof, isotopic analysis
has been introduced recently as an additional step in a systematic methodology of origin
assignment. These techniques are based on the fact that the major elements of organic
exist in their naturally-occurring isotopic form (13C, 2H, 18O, 15N). The isotopic
composition of natural products is determined by the biosynthetic pathway that has
produced the compound, and depends also on geographical origin. Their use in the
authentication of food products, for example to distinguish between cane and beet
sucrose, is now a routine application for a majority of food control laboratories.
There are two means of measuring isotopic ratios. Isotope ratio mass spectrometry
(IRMS) measures overall isotope content of a product or isolated compound. Nuclear
Magnetic Resonance (NMR) on the other hand can be used to determine site specific
isotope ratios on individual sites in a molecule. The combination of both techniques
provides a complete characterisation of a chemical compound.
Isotopic analysis can provide information on the geographical origin of natural drugs
from plant origin such as cocaine. In addition, the isotopic fingerprint can be used to
identify the synthetic process used in semi-synthetic drugs, such as heroin or LSD, and
in synthetic products, such as amphetamines. This information can be used to identify
common batches of products and lead the investigators to the producing laboratories.
13
C measurement using on-line GC-IRMS have been used to differentiate between
different seizures of illicit heroin. The acetylation of morphine leads to a modified 13C
content in the resulting diacetylmorphine which can be linked to the acetylating agent
used. A multi element isotope determination of cocaine and heroine based on IRMS
measurements of 15N, 13C and 2H have shown the potential of this technique to
discriminate between batches of similar or different origin.
Work has also been carried out using combined site specific NMR and IRMS on
chemically related compounds such as nicotine and caffeine. The multi-element and
multi-site isotopic analysis of nicotine extracted from tobacco leaves has provided
information of the intramolecular distribution patterns in tobacco alkaloids which can
be interpreted in terms of biosynthetic metabolism and the influence of environmental
factors. Combined with compositional data, this information has been used for the
origin assignment of tobacco. Using similar methodology, an intramolecular distribution
pattern could be built up for various illicit substances which would provide considerable
insight into the synthetic methods used to produce the drugs.
5. SCIENTIFIC AND TECHNOLOGICAL OBJECTIVES
The main research objectives are :

To extend existing stable isotope methodology based on IRMS determinations of
13
C and 15N to other compounds

To investigate the potential of 18O data in origin assignment of illicit substances
DC 10/99/Topic II.11/ Pg 3

To apply site specific isotopic techniques using NMR to develop intramolecular
isotopic distribution patterns in order to investigate synthetic processes and
geographical origin
The priority list of illicit substances to be studied is as follows :
- Heroin
- Cocaine
- Cannabis
- Synthetic products (synthetic phenylacoylamines such as ecstasy, serenity, 2CB)
6. ECONOMIC AND SOCIAL BENEFITS
Drug abuse is not just a national but a European, even International, problem. Any
methodology that can contribute to identifying distribution networks and to providing
clear and conclusive evidence for use in criminal investigations has considerable social
benefits.
The figures published every year show that drug abuse in particular by younger and
younger members of the population is on the increase. Amphetamines have been used
by 1 to 13% of 15-16 year-olds. Ecstacy by 1 to 9% and LSD by 1 to 10%. Lifetime
cannabis use of 15-16 year-olds ranges from 3 to 5% (Finland, Greece and Portugal) to
around 40% (Ireland and the United Kingdom1. A pilot study by the OEDT2 reported on
the increased incidence of urban delinquency linked to drug taking. It particularly made
the point that the problem was a European one, affecting European towns and that only
a concerted effort on a European scale, a sharing of experience and transfer of expertise,
would be effective in reducing the extent of the problem.
A further worry for European citizens is the increasing number of synthetic drugs now
available on the market. A further report by the OEDT Department of Epidemiology
published in 1997 based on drug seizures showed that the consumption of ecstacy and
other amphetamines was increasing. In addition mixtures of different compounds and
products of dubious quality and purity have been found on the market – sometimes with
disastrous, even mortal, consequences.
Methods which aid in the international control of drug abuse can only be of benefit to
society as a whole.
7. TIME SCALE
There are no specific time-scale requirements for this topic.
1
2
Annual report on the state of the drugs problem in the European Union, 1999
Observatoire Européen des Drogues et de Toxicomanies, 1996