Evaluating wastewater surveillance for estimating pharmaceutical use

Area of Science:

• Environmental Chemistry
• Pharmaceutical Sciences
• Public Health

Background:

• Regional medicine use data is vital for health management but often unavailable globally.
• Wastewater analysis offers a potential solution for estimating drug consumption where traditional data is lacking.

Purpose of the Study:

• To assess the efficacy of analyzing active pharmaceutical ingredients (APIs) in untreated municipal wastewater for predicting regional medicine use.
• To establish conversion factors (CFs) for estimating drug usage from wastewater data.

Main Methods:

• Measured 53 APIs in Stockholm wastewater treatment plant (WWTP) influent from 2004-2021.
• Correlated API measurements with comprehensive regional sales data as a proxy for medicine use.
• Generated and evaluated conversion factors (CFs) using wastewater and sales data, assessing variability and predictive performance.

Main Results:

• Wastewater-recovered API mass generally aligned with estimated daily use, with CFs varying significantly across APIs.
• Estimated typical prediction error was less than 2-fold for 68% of APIs when validated on independent data.
• CFs were stable over time for 43 APIs (variability <100%) and predictions correlated well with international studies.

Conclusions:

• Wastewater-based estimation of medicine use is feasible for most APIs with a typical error of less than 2-fold.
• This approach supports wastewater surveillance as a tool to address data gaps in regional drug consumption.
• Limitations exist, particularly for detecting small changes in medicine use.