Amphetamine-type stimulants (ATS) are the second most widely used stimulant drug in Europe today, far ahead of cocaine in some Member States. Eighty percent of ATS used in Europe is produced locally, most of it in industrial-sized facilities run by organised criminal groups. In addition to the societal implications, ATS production poses important health and safety risks even to non-users. Chemicals used in production can lead to fires and explosions and most production waste is typically dumped into the public sewer system, posing significant environmental and health hazards. All this illegal ATS-related discharge may be a goldmine for law enforcement authorities. The pioneering EU-funded microMole project set out to exploit it for the public good. As project coordinator Fernando Solano explains, “Our objective was to design and pilot a device for automatically detecting the production of amphetamine in urban environments using the sewage network to aid law enforcement agencies.”
Sewer networks provide cover that rivals that of Latin American jungles
Simplicity in concept is not reflected in the many technical challenges of device realisation given the complicated and hostile urban sewer environment. There are a myriad of small particles, organic compounds, chemicals, bacteria and other substances in sewers posing problems of filtration as well as sensitivity. Wireless transmission can be attenuated rapidly by the water stream, its sediments and the surrounding pipe materials and earth. Keeping the device running in the watery depths of the sewers is not a trivial task, yet imperative for continuous data retrieval, analysis and transmission. MicroMole brought together leading industry experts and engineers, law enforcement authorities and even lawyers with detailed knowledge of legal evidence collection and prosecution to get the job done. An active microfluidic system overcame clogging and enabled short sampling time along with the elimination of cross-contamination during sample collection. Augmented power availability with additional batteries and lowered power consumption with innovative solutions for low-power remote monitoring helped meet the challenges for power and data communications over time in the watery depths of an urban sewage system. Among innovations were low-power microcontrollers and novel algorithms for data compression and scheduling of wireless transmission. The team faced one last hurdle – placing the system in small pipes difficult to access by humans.
Planting the ‘mole’ where the action is
The prototype is a series of three hollow rings that fit to the walls of a pipe to avoid blocking wastewater flow. A patent-pending crawler robot carries the system through small pipes, and then assembles and mounts it at a fixed point in the sewer system. As Solano summarises: “There were many technical challenges that we had to overcome – a wireless network operating in the sewer environment, identification of a chemical substance in a sample containing anything and everything, and putting it in a small space without blocking sewage flow… and we did it!” The pilot demonstrated the feasibility of wireless monitoring of sewage waste and outcomes are already being exploited within the EU-funded project SYSTEM. The device has far-reaching potential for public and environmental health and safety, detecting not only drug-related activity but also the unlawful disposal of harsh chemicals of many kinds.
microMole, sewer, amphetamine-type stimulants (ATS), sewage, wireless, amphetamine, urban, authorities, law enforcement