Antimicrobial resistant genes (ARGs, group C, Table ) were also included in this study to explore an integrated approach towards risk assessment. As a range of AAs were explored in this project, an additional three river samples were collected to investigate several ARG targets via digital PCR (dPCR). All PCR reagents were purchased from Thermo Fischer. The chosen ARG targets were ermB, sul1, intI1, qnrS, bla-CTX and bla-TEM. Additionally, 16S rRNA was analysed for information about bacterial population and a TaqMan™ Universal DNA Spike in Control (Thermo Fisher) was spiked into the lysis step of the DNA extraction kit (10 μL) to assess extraction efficiency of the kit. To filter river water on site for DNA extraction, Whatman ® plastic filter holders (47 mm) were purchased along with sterilised cellulose filter papers (0.2 μm, Merck). Holders and filter papers were autoclaved inhouse following manufacturer's instructions.