Governments were doing that kind of sampling before Covid too, eg for drugs. https://www.bath.ac.uk/announcements/study-tracks-illicit-drug-use-through-europes

Governments were doing that kind of sampling before Covid too, eg for drugs. https://www.bath.ac.uk/announcements/study-tracks-illicit-drug-use-through-europes-sewage-system/ https://www.bath.ac.uk/announcements/study-tracks-illicit-dr...