This is a guest blog by Lydia Niemi from the Environmental Research Institute, University of the Highlands and Islands, on pharmaceutical pollution and its potential implications for the environment and human health in Scotland. SPICe was introduced to this research through the Scottish Policy and Research Exchange (SPRE), an organisation which helps to connect researchers with policymakers, including in the Scottish Parliament and Scottish Government, with a view to support evidence-based policy.
As with all guest blogs, what follows are the views of the authors, not those of SPICe or indeed the Scottish Parliament.
Pharmaceutical medicines are extensively used in everyday life. This is in response to our growing, ageing population, new technological advances, and the “pill for every ill” culture. According to the Scottish National Health Service (NHS), prescribing rates in Scotland have increased by approx. 37% over the past 14 years, with more than 103 million prescription items prescribed in 2018-19 (an increase from 75 million items in 2004-05). Pharmaceutical expenditure (include costs of manufacturing, packaging and distribution) also represents a large portion of the wider Scottish and UK economies. NHS Scotland spends more than £1 billion per year dispensing medicine items and services. However, pharmaceuticals are now classed as emerging environmental contaminants due to pollution associated with human use.
How do pharmaceuticals enter the environment?
After administration, many pharmaceuticals are not fully processed in the human body and are subsequently excreted into wastewater. Additional activity such as washing off topically applied medical creams, and improper disposal down the sink or toilet, adds to this. Hospitals and care facilities are key sources for pharmaceuticals entering municipal sewers. A study in Scotland reported hospital contribution of antibiotics and x-ray contrast agents accounted for 75 – 100% of the total load of these pharmaceuticals in municipal wastewater. However, other significant sources of pharmaceuticals into urban wastewater include waste from pharmaceutical manufacturers, homes, and businesses (see figure below). Veterinary medicines used in the agricultural and fisheries industry may add further compounds into water. In most cases this waste will not go through municipal wastewater treatment and may enter the environment directly.
The entrance of pharmaceuticals into wastewater treatment plants (WWTPS) across the UK and Europe has been well documented (see for example this study from 2017 or this one from 2018). WWTPs were not designed to remove micropollutants such as pharmaceuticals from wastewater, and many compounds undergo limited elimination during treatment. Advanced, chemically demanding disinfection techniques may offer further removal, but at the risk of forming partially degraded and unidentified compounds with unknown environmental effects. These advanced treatment techniques are also energy-intensive and may be financially or logistically challenging to implement. Small and conventional WWTPs, such as those used in rural communities, may struggle to cope with pollutant removal as infrastructure ages, populations grow, and pharmaceutical use and diversity continues to increase.
Why should we care about pharmaceuticals in the environment?
With the release of wastewater effluent into surface water, pharmaceuticals have a direct pathway into the environment. More than 630 pharmaceutical compounds have been detected in rivers, lochs, seas, and estuaries around the world, with number and concentrations of antibiotics, anti-inflammatories, and analgesics (medicines used to relieve pain) topping the list.
The subsequent environmental impact of this widespread presence is not fully understood. However, behavioural changes in aquatic species have been reported, such as altered salmon migration in the presence of anti-anxiety drugs. Similarly, impaired development was observed in frogs exposed to antidepressants and endocrine-disrupting disease (affecting reproduction, neurological and immune functions) in fish exposed to estrogen hormones. Also, antibiotics in surface water have been found to accelerate development of antimicrobial resistance in bacteria.
The impact is not limited to the environment. Pharmaceutical pollution may also result in contamination of potable drinking water sources. Presence has also been reported in soil after irrigation with reclaimed wastewater and after fertiliser application with treated sewage sludge. This may result in pharmaceutical detection in crops, as observed in potatoes, carrots, and tomatoes, and soybeans.
Concentrations of pharmaceuticals within drinking water and food would be below the effective concentration of the individual drugs. However, there is uncertainty on whether exposure to sub-therapeutic doses, and exposure to complex mixtures, will lead to negative effects in human health. More research is needed to assess the environmental risks of pharmaceuticals, and associated health impact.
In Scotland, monitoring pollutants in surface water is necessary under Scottish Water and Scottish Environment Protection Agency regulations. Currently, pharmaceuticals do not have environmental quality standards in the UK or Europe for maximum permissible concentrations in wastewater discharge and surface water. The Water Framework Directive surface water Watch List requires pollutant monitoring of priority substances (including pharmaceuticals) across the EU. This monitoring data is assessed to determine if significant environmental risks are posed by pollutants, and whether environmental quality standards should be set at the EU level.
Following the UK’s exit from the EU, Scotland will continue to be free to develop national standards for pharmaceuticals as river basin specific pollutants under the Scotland River Basin District (Standards) Directions. However, the Scottish and UK governments may work together to set environmental quality standards post EU exit to address common pollutants and sectoral issues across the UK.
Cross-sector work in Scotland and the One Health Breakthrough Partnership
Scotland has a vested interest in the Hydro Nation and One Health agendas, which are multi-sector strategies to effectively manage the water environment and improve public health (respectively). These concepts recognise that human health and environmental health are closely interconnected, and that water quality is a central and significant factor to the wellbeing of both.
Many parts of the private and public sectors across Scotland and the UK may be affected by pharmaceutical pollution and have an interest in addressing this issue. This includes pharmaceutical manufacturers and the healthcare sector, the food and drink sector (including agriculture and fisheries), and public organisations including water regulators, environmental protection bodies, researchers/academics, and policymakers.
In response, the Environmental Research Institute (University of the Highlands and Islands) formed a partnership with stakeholders (NHS Highland, Scottish Environment Protection Agency, Scottish Water, and Highlands and Islands Enterprise) and research institutes (the James Hutton Institute, Scotland’s Centre of Expertise for Waters) to investigate this issue.
This One Health Breakthrough Partnership (OHBP) is a cross-sector benchmark group providing leadership in the field and sharing expertise and resources to execute its vision for a non-toxic environment (see figure below). Work to date has included analysing pharmaceutical pollution in hospital wastewater, researching antimicrobial resistance in water, and preparing a national database on pharmaceuticals detected in the Scottish environment with Glasgow Caledonian University. The national database was mapped to visualise pharmaceutical pollution across Scotland and has been used to identify spatial trends in the dataset and assess the potential risk of antimicrobial resistance and environmental effects of pharmaceuticals. The project report is expected in autumn 2020.
The OHBP is also dedicated to raising public awareness and exploring sustainable solutions to address pharmaceutical pollution. This has involved:
- Media campaigns and panel discussions on the current issue and the OHBPs mission and work.
- Developing teaching tools on antimicrobial resistance and appropriate methods for medicine disposal.
- Piloting a “greener” prescription formulary (list of medicines) in the NHS Highland region to encourage a reduction in the prescription (where possible) of compounds of high environmental risk.
- Exploring separate treatment of hospital wastewater, and researching sustainable methods for enhancing pharmaceutical removal in WWTPs.
- Recently, the OHBP’s work resulted in Caithness General Hospital (Wick, Highlands) receiving the international Alliance for Water Stewardship award for its commitment to improve water use and reduce environmental impact from hospital waste.
Research undertaken by the OHBP and partner universities will provide evidence to policymakers on pharmaceutical pollution and sustainable solutions to reduce impact. This may support policy changes in future for new regulatory standards to safeguard Scotland’s environment.
Lydia Niemi, Environmental Research Institute, University of the Highlands and Islands