The Department of Legal Medicine has been testing waste water for drugs since January 2023, and its first provisional results arrived this week.
On Friday and Saturday, the spring congress of the German Society of Forensic Medicine was held at the National Health Laboratories (LNS) in Dudelange. This was a first for Luxembourg Forensic Medicine, which is celebrating its 10th anniversary this year.
Luxembourg's forensic medicine also includes the Department of Analytical Chemistry, which has been testing wastewater for drugs in Luxembourg since January 2023 and presented its first provisional results at the congress.
The aim is to find out whether the consumption of recreational cannabis by Luxembourgers has increased following its legalisation in July 2023. To this end, samples were regularly taken from the three wastewater treatment plants in Bivange, Beringen and Mamer, explains Serge Schneider, head of the analytical chemistry department.
"We get a litre of water from these plants once a week and we measure it for a certain number of drugs, especially cannabis. The first preliminary results do not show huge differences."
Luxembourg among the top 20 consumers
While consumption has not increased significantly, Luxembourgers still smoke a lot. The Grand Duchy is in the top 20 on a European level.
"We found cannabis in all 150 analyses carried out last year. And cocaine too, by the way. We are definitely among the top consumers when it comes to cannabis, but other European countries face similar problems," Serge Schneider relativises.
After all, Luxembourg is not an island. The hard drug fentanyl has not yet been found in the Grand Duchy, but this might only be a matter of time.
© Anne Wolff
How are rates measured?
For each analysis, the laboratory needs about 100 millilitres of waste water. The cannabis content in the water is measured in nanogram per litre and then extrapolated to milligrams per thousand people per day.
The results are preliminary, more analyses and more time are needed to be definitive. There are also uncertainties that influence the results, such as the weather, the number of people connected to the sewage treatment plants, the stability of the drugs in the water and the large number of cross-border workers.
Nevertheless, Serge Schneider's team can compare consumption over time and with other countries. The sample has been expanded to include two further wastewater treatment plants in the country.
As far as the cleanliness of the water is concerned, there is no need to worry. The wastewater treatment plants filter out such residues thoroughly, Serge Schneider assures.
© Anne Wolff
