Emerging contaminants of concern
We collected 12 months of water samples from the River Chess to look at chemical content.
There are thousands of chemicals in use today in domestic, commercial and industrial settings, many of which fall outside of regulatory frameworks, meaning they are not monitored.
We therefore decided to explore what chemicals of potential ecological concern were present in the River Chess, and investigate where they might be entering the river by sampling different locations of the river on a monthly basis.
River water samples were collected entirely by our citizen scientists between July 2022 and June 2023.
Once collected, our water samples were sent off to Imperial College London who can identify concentrations of up to 200 chemicals, some of which are on the EU Water Framework Directive Watch List.
Eight sites were sampled along the River Chess from Chesham to Rickmansworth, including one groundwater source within Latimer Meadow.
Passive samplers
As part of this work, we also deployed passive samplers into the River Chess in June and November 2022, for one week at a time at nine different locations.
Passive samplers are 3D printed dots used to detect the presence (not concentrations) of up to 2,500 chemicals in the river.
The passive samplers absorb all chemicals within the river during their deployment, and will hopefully show us seasonal differences between dry (June) and wet (November) periods.
Results from the River Chess
We are pleased to share the final report detailing our results from th River Chess.
As you’ll see in the report below, we mainly found pharmaceuticals in the River Chess, followed by illicit drugs and insecticides.
What comes next?
After receiving the report and sharing this with our citizen scientist working group for those involved in the sampling, we have decided to further research 3 insecticides that were found to be of potential medium ecological risk in this study.
From this research, we aim to create a local awareness campaign detailing what products may contain these insecticides and what alternatives could be used that are less harmful to aquatic life.
Citizen scientists at work
Since this study started in summer 2022, we’ve had some incredible dedication shown by our citizen scientists in the collection of the water samples from both urban and rural locations – some requiring distance walking all while carrying a long-handled dipper stick!
We can’t thank each of them enough for their efforts.
Get involved
Keep up to date
