Chemical Engineering @ChemengFiles.Com

Investigators from the Consejo Superior de Investigaciones Científicas (CSIC), the Research Center for Energy, Environment and Technology (CIEMAT) and the Catalan Institute for Water Research have developed the first method of analysis for the detection of drugs in the air. The system, described in Analytical Chemistry, a tool that can provide insight into the evolution of drug use in the population, quickly and anonymously using the samples collected by the network of air quality.

To develop the methodology, the team analyzed 17 compounds belonging to five classes of drugs (cocaine, amphetamines, opiates, cannabinoids and lysergic acid) in various air samples collected at two air quality stations in Barcelona and Madrid. In all samples found levels of cocaine and a cannabinoid, the tetrahydrocannabinol (THC). In any case, the results, the researchers caution, are not representative of the whole city, because "at this early stage we have focused on fine-tune the methodology and therefore the samples are only very specific areas ", explains researcher Xavier Querol CSIC, one of the directors of the study.

By quantity, the higher levels correspond to cocaine, which was found in concentrations of 29 to 850 picograms per cubic meter of air (a picogram is one billionth of a gram). Heroin has also been found in detectable levels in samples from Madrid, but not in Barcelona, with levels up to 143 picograms per cubic meter. One possible explanation, say the authors of the paper is that the sampling and measurement station in Madrid is relatively close to a neighborhood where there is a potential drug trade, and also in the vicinity there is a dilapidated building that is believed to Used for consumption.

The tetrahydrocannabinol, the benzoylecgonina (a derivative of cocaine, for example in the present crack) and 6ACM (derived from heroin) were found in samples at levels of between 23 and 33 picograms per cubic meter, while the compounds amphetamines were detected in all cases at levels less than 5 picograms per cubic meter.

Another interesting fact is that the samples collected over several days, show higher concentration of the compounds over the weekend, suggesting an increase in consumption during this period of time.

CSIC researcher Damian Barceló explained that the levels measured do not pose any danger to human health. According to Xavier Querol, research professor of the CSIC, "In the case of cocaine in Barcelona, it is at levels similar to those of some heavy metals such as cadmium and bismuth, the usual air pollutants." Moreover , according to Miren Lopez de Alda, CSIC researcher, "or living 1000 years come to consume the equivalent of one dose of cocaine to breathe this air."

Furthermore, the researcher Xavier Querol insisted that "in no case these levels should be considered as representative of the air of Madrid and Barcelona, because the study was conducted based on two very specific points and knowing that there were drugs in their environment. "However Viana Mar, another of the researchers of the CSIC's research work and stresses that" the results of this study show relatively high levels when compared with the few areas of Europe where similar studies have been performed " . The latest study is one conducted in 2007 in the Italian cities of Rome and Taranto, where levels of cocaine were found about 100 picograms per cubic meter, Viana added.

To perform the analysis, the researchers installed two air quality stations around quartz microfiber filters that retain particles that are suspended. This allows pollutants to accumulate that are present in about 730 cubic meters of air (a person breathes between 15 and 20 cubic meters per day). Subsequently, the filters are analyzed with a methodology that combines liquid chromatography and mass spectrometry, a technique that provides a high reliability of results. "Samples of the air quality networks can be used to detect and monitor drug use," says Mar Viana and Xavier Querol.

The work is led by researchers at the CSIC and Damia Barceló Xavier Querol. Authors are also researchers at the CSIC Miren Lopez de Alda, Mar Viana and Andrew Alastuey also Begoña Artiñano researcher CIEMAT.

Importantly, this study is one of the first joint work between the departments of Chemistry and Environmental Geosciences of the newly established Institute for Environmental Assessment and Analysis of Water (CSIC) in Barcelona.