Though the sampling linked to chemical/pharma/industry WWTP is on effluent basis, these effluents will still undergo municipal WWT if they are discharged from the factory and not reused in the process (based on volatility accumulation less likely?), so direct exposure is only relevant for “A” (scariness of that depending on the evaluation of Paustenbach 2024 and the overall fluctuations I guess). Regulators would agree and check specifications of the effluent prior to discharge, this can be process risk-based (non-compliance can lead to fines). The municipal WWTP as next step might have the “classic risk profile” for nitrosamines (as it seems Switzerland is a country still applying chlorination occasionally?
swiss-food.ch - Facts about drinking water and limit values)
Interestingly, pharmaceutical site sampling was done in an early phase in perspective of the call for review on nitrosamines (while it remains difficult to assess if the nitrosamines are linked to the water treatment itself (formation or limited removal compared to optimized processes) or the high nitrosamine content in the influent). It also concerns spot checks, no big dataset. To identify if nitrification in the WWTP is under control more data can be useful.
But it’s true that nitrosamines in waste water in a complicated science on its own with much historic research as well. And the call for review data and knowledge probably makes it easier to evaluate and understand risks for nitrosamines in pharmaceutical waste water and translate that to Environmental management and specifications for discharge of industrial water.
An interesting one to add is activated carbon as well, to remove some nasty chemicals from industrial/chemical/pharmaceutical waste water prior to discharge to the municipal waste stream (no industrial WWTP), however activated carbon can promote the formation of nitrosamines from certain amines in the waste, not necessarily retained on the activated carbon.