Psychoactive Substances in Airborne Particles in the Urban Environment

Abstract

The Earth’s atmosphere is affected by the presence of psychotropic chemicals, both licit and illicit substances, not only in major city centres but also in suburban and rural regions. Dedicated analytical procedures, most of them based on gas or liquid chromatography coupled to mass spectrometry, have been optimised for the detection of these substances. Nicotine and caffeine (licit substances), are widespread in the world at concentrations sometimes reaching 100ng/m3. Conversely, drugs of abuse (namely cocaine, cannabinoids, heroin and amphetamines, which are in most countries illicit) rarely exceed 1ng/m3 each. However, their presence in airborne particles is virtually ubiquitous in agreement with what was observed in the past for surface and waste waters. The spatial and temporal variability of psychotropic substances in the atmosphere has been an object of study in different types of urban areas, whereas data are scarcer for rural areas. In the current ambient concentrations, personal exposure to airborne drugs of abuse may be considered negligible, posing no harm to human health. The possibility of drawing abuse prevalence indicators from the drug contents in the air merits, however, to be explored.