Tracking changes in the occurrence and source of pharmaceuticals within the River Thames, UK: from source to sea

There is a growing interest in the occurrence and sources of pharmaceutical substances in the environment. This paper reports the first detailed transect of pharmaceutical occurrence along the River Thames, UK, from source to sea, undertaken during a period of high flow in 2016. In 37 samples a total of 41 pharmaceuticals and 2 lifestyle compounds (cocaine and sucralose) were detected. Total concentration of pharmaceuticals ranged from 0.0012 µg/l to 10.24 µg/l with a median of 2.6 µg/l. Sucralose concentrations varied from