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Reduction of pharmaceuticals in the water environment: Baseline assessment and recommendations


Wastewater treatment works are not able to fully remove all pharmaceuticals and their metabolites, leading to the unintended release of these compounds in the water environment. These substances can be ecotoxic, bio-accumulate, and contribute to the introduction/spread of anti-microbial resistant bacteria and other microorganisms in the environment. The waste streams containing these pharmaceutical compounds originate from many sources, but are particularly concentrated from hospitals and associated wastewater treatment plants although for commonly used medicines domestic use is widely recognised as the overall greatest source. Increased wastewater treatment alone is not a sustainable method to keep pharmaceutical compounds from entering the water environment. Source control is a key part of the solution to protecting the water environment. 

The concept of “Essential Medicines,” introduced by the World Health Organisation in the 1970s, provided a list of medicines that were selected based on safety, clinical effectiveness, and cost effectiveness. This idea has been widely adopted, with the Stockholm Wise List updating this concept to incorporate environmental considerations. Where clinical and cost effectiveness of medicines are equal, then the environmental impact of the medicines is considered to decide which should be the preferred choice on the formulary (i.e. list of medicines available to the prescriber). Updating local formularies to include environmental considerations potentially reduces negative impacts of pharmaceuticals and their metabolites on the water environment by ensuring prudent prescribing choices.  

Performing a similar formulary update in Scotland requires adapting this list to be relevant to the pharmaceuticals of concern in Scotland as well as developing a method to link this new information into the existing NHS prescribing system and inform prescribers and patients of the changes. The Green Breakthrough Partnership plans to update the NHS Highland formulary to incorporate environmental effects as a pilot.  Prior to making any changes to existing Scottish NHS formularies, the baseline levels for both the existing water environment data and prescription numbers for these pharmaceuticals need to be assessed. Establishing a baseline enables the future assessment of the impact of the study.

The project will focus on a list of pharmaceuticals, identified through consultation with the project steering group by prioritising chemicals that a) are of concern to Green Breakthrough Partners because of their environmental impact, b) have the potential to promote antimicrobial resistance, and c) are commonly prescribed by the NHS. 

Project Objectives

  1. Assess the spatial and temporal availability of baseline data in Scotland (e.g. prescription data, environmental monitoring data, discharge data), and identify gaps in the datasets, including any quality concerns.
  2. Provide recommendations for small-scale data gap filling i.e. targeting monitoring campaigns or changes to existing programmes (e.g. extension to SEPA’s WFD Watchlist monitoring).
  3. Provide initial recommendations on visualising the baseline dataset and related information based on the findings of objectives 1 and 2 to inform a potential follow-on project.