Calendar An icon of a desk calendar. Cancel An icon of a circle with a diagonal line across. Caret An icon of a block arrow pointing to the right. Email An icon of a paper envelope. Facebook An icon of the Facebook "f" mark. Google An icon of the Google "G" mark. Linked In An icon of the Linked In "in" mark. Logout An icon representing logout. Profile An icon that resembles human head and shoulders. Telephone An icon of a traditional telephone receiver. Tick An icon of a tick mark. Is Public An icon of a human eye and eyelashes. Is Not Public An icon of a human eye and eyelashes with a diagonal line through it. Pause Icon A two-lined pause icon for stopping interactions. Quote Mark A opening quote mark. Quote Mark A closing quote mark. Arrow An icon of an arrow. Folder An icon of a paper folder. Breaking An icon of an exclamation mark on a circular background. Camera An icon of a digital camera. Caret An icon of a caret arrow. Clock An icon of a clock face. Close An icon of the an X shape. Close Icon An icon used to represent where to interact to collapse or dismiss a component Comment An icon of a speech bubble. Comments An icon of a speech bubble, denoting user comments. Comments An icon of a speech bubble, denoting user comments. Ellipsis An icon of 3 horizontal dots. Envelope An icon of a paper envelope. Facebook An icon of a facebook f logo. Camera An icon of a digital camera. Home An icon of a house. Instagram An icon of the Instagram logo. LinkedIn An icon of the LinkedIn logo. Magnifying Glass An icon of a magnifying glass. Search Icon A magnifying glass icon that is used to represent the function of searching. Menu An icon of 3 horizontal lines. Hamburger Menu Icon An icon used to represent a collapsed menu. Next An icon of an arrow pointing to the right. Notice An explanation mark centred inside a circle. Previous An icon of an arrow pointing to the left. Rating An icon of a star. Tag An icon of a tag. Twitter An icon of the Twitter logo. Video Camera An icon of a video camera shape. Speech Bubble Icon A icon displaying a speech bubble WhatsApp An icon of the WhatsApp logo. Information An icon of an information logo. Plus A mathematical 'plus' symbol. Duration An icon indicating Time. Success Tick An icon of a green tick. Success Tick Timeout An icon of a greyed out success tick. Loading Spinner An icon of a loading spinner. Facebook Messenger An icon of the facebook messenger app logo. Facebook An icon of a facebook f logo. Facebook Messenger An icon of the Twitter app logo. LinkedIn An icon of the LinkedIn logo. WhatsApp Messenger An icon of the Whatsapp messenger app logo. Email An icon of an mail envelope. Copy link A decentered black square over a white square.

Eulyn Pagaling: Knowing what’s in Scotland’s rivers can help us to take better care of them and ourselves

Data will help us to better understand the levels of pollution, including pharmaceuticals and microplastics, in our water.

Aberdeen's beautiful River Dee (Image: richardjohnson/Shutterstock)
Aberdeen's beautiful River Dee (Image: richardjohnson/Shutterstock)

In Scotland, we’re blessed with the most stunning landscapes. And, with 125,000km of rivers and streams in the country, from Highland burns to wide, lowland rivers like the Tay, we’re particularly lucky.

But it may come as a surprise that there are very many potential contaminants in these wonderful waters. It may also be a surprise that many of those contaminants are what we put into our systems. In other words, they come from us.

They’re what’s left of the paracetamol, ibuprofen, antibiotics and other medicines that we take on a daily basis. Our bodies don’t absorb a large amount of these, and they get flushed into the sewerage system. Because not all sewage treatment facilities can remove these chemicals, they ultimately end up in our rivers and/or the sea.

Here at The James Hutton Institute, we’ve looked at the pharmaceutical pollution in detail in the River Dee. It’s an iconic river, running 140km from high up in Scotland’s Cairngorm Mountains down to where it flows into the sea at Aberdeen harbour mouth. The results wouldn’t look out of place in the average bathroom cabinet.

Research by my colleague Dr Zulin Zhang discovered that paracetamol was the most commonly found compound. But there was also oestrogen (the female hormone), antibiotics and hallucinogens. While the concentrations of all were extremely low and around the Scottish average, over a year we estimated that 148kg of the most prevalent pharmaceutical – paracetamol – was going into the river per year.

It’s important to say that the levels of pollution found, even as a worst-case estimate, didn’t pose a risk to humans, and these pharmaceuticals don’t get released into rivers everywhere. In cities, where there’s a greater population density, the treatment works tend to be more intensive, so remove more of these contaminants.

While our waste dominates the pollution we’ve looked at, there are also other sources, like septic tank release and when sewage sludge applied to fields gets washed away into rivers. These have been found to contain paracetamol, too, but also antibiotics, caffeine and even insect repellent used to deter our famous midges.

It’s complex but, as so much of this pollution comes from us, we do have to ask questions about what and how much of it we’re consuming – do we always need it? Also, what about the effects the increasing mix of different things we’re putting into rivers could have on wildlife, as well as water quality?

And what happens when the hotter weather means rivers start to get shallower and the pollution more concentrated? What will be the impact on nature?

Without data it’s hard to build a picture of what’s going on

There are a lot of unknowns. We don’t yet fully know the impact all this has on the smallest life in our rivers – bacteria – which all other life relies on, for example. We don’t know much about how antibiotics in the water can create antimicrobial resistance in bacteria in the water, or if that can then reach us.

We don’t have the answers yet, but we’re working on it. We’re looking at what antibiotics are doing to bacteria. We’re also gathering data.

Without data it’s hard to build a picture of what’s going on. So, through a Scottish Government-funded project, my colleague Dr Lisa Avery is leading work to build a baseline to show levels of pollution, including pharmaceuticals, microplastics and forever chemicals, in Scotland’s rivers. It will be the first national baseline of Scottish river pollution to see trends, and predict what might happen in different scenarios.

An estimated estimated 148kg of paracetamol ends up in the River Dee every year (Image: Kenny Elrick/DC Thomson)

We’re using new types of sensors to gather data that we can then use to develop models to help us understand how pollutants enter and move around the environment, and help us to deal with them better. We’re even drilling right down to looking at what organisms are in our rivers by using environmental DNA. This lets us profile the life in our rivers.

Another colleague, Dr Miriam Glendell, is working with partners to help those who prescribe medicines to pick ones that are more environmentally-friendly. Looking at green and blue prescribing where appropriate could also be a great option – offering people time in nature, whether that’s woodlands or wetlands, instead of pills, for example.

There’s a lot of work to do, and we can all play our part in the decisions we make in our daily lives. We live on the doorstep of some stunning rivers. Let’s take the best care of them.


Dr Eulyn Pagaling is an environmental microbiologist for The James Hutton Institute