Scientists at the Spanish Council for Scientific Research (CSIC) in Barcelona have developed a new method for monitoring the consumption of drugs of abuse in the general population
This method, which was developed using analytical laboratory technology from Applied Biosystems/MDS Analytical Technologies, can measure the levels of substances such as cocaine, amphetamines and cannabis in water from sewage treatment plants to estimate the amounts of various illegal drugs being consumed within specific regions of the country.
The method provides a fully automated, faster and more specific way for estimating drug abuse than has previously been possible, and was published in the May 2008 issue of the scientific journal Analytical Chemistry.
Traditional methods for estimating drug abuse in the population can be costly and inaccurate, relying on surveys and on social, medical, and criminal statistics.
In contrast, this new method uses mass spectrometry to test water from sewage treatment plants and provide accurate, real-time data extremely quickly and without invading the privacy of members of the public.
The method's increased speed and efficiency also reduces labour and administrative costs.
The use of mass spectrometry-based methods to determine drugs of abuse in sewage and surface waters was developed a few years ago, and this latest development is the first fully automated technique for detecting and measuring multiple compounds simultaneously, offering improved analytical performance and reliability.
This enabled the CSIC scientists in Barcelona to investigate sewage water samples from regions of Barcelona and Valencia for the presence of 19 different compounds simultaneously.
The compounds were from five different classes of drugs: cocaine and related substances, amphetamine-like drugs including ecstasy (MDMA), opiates including heroin and morphine, cannabinoids and LSD and related products.
Eight of these compounds, including heroin and LSD products, had not previously been analysed in water samples.
The scientific team reported that cocainics were found in the highest quantities, followed by amphetamine-like compounds, opiates, cannabinoids, and LSD and metabolites.
Samples from Barcelona showed higher levels of cocainics and morphine, and lower levels of cannabinoids, when compared with drug levels in samples from Valencia.
The presence of morphine may be due at least in part to its use as a strong analgesic for medicinal purposes.
The levels of cocainics and amphetamine-like compounds reported in this study were generally higher than those reported in previous studies.
"The new method offers considerable cost and time savings to water analysis laboratories, and will assist the authorities in monitoring drug abuse on a regional basis," said Damia Barcelo, full research professor and head of the CSIC department of environmental chemistry, in Barcelona.
"The Applied Biosystems/MDS Analytical Technologies mass spectrometry technology is essential to the process because it can work with much smaller sample volumes than other available systems require." The investigations were conducted using a 4000 QTrap LC/MS/MS system from Applied Biosystems/MDS Analytical Technologies to analyse the water samples.
The 4000 QTrap is a premier hybrid triple quadrupole/linear ion trap mass spectrometer that can identify, characterise and quantitate metabolites with high mass accuracy and resolution.
It offers unmatched quantitative and qualitative performance within a single system, making compound identification faster and easier, and providing researchers with confidence in their results.
The 4000 QTrap was an essential technology for enabling the new method because of unique features that include its ability to work with much smaller sample volumes than previously established methods, which allows easy storage and freezing of the samples.
This not only halts any biological activity within the samples that might affect the analysis, but also avoids the risk of contamination or alteration of the sample that could be caused by addition of preservatives.
Until now, small sample volumes were not used because they risked compromising the method sensitivity; however, the detection capabilities of the 4000 QTrap system overcome this issue.
This system allows the simultaneous analysis of multiple compounds in a single run and at very low detection limits, in the low nanogrammes or picogrammes per litre range after sample pre-concentration of 5ml.
