BGS-UKRI briefing note: tryptophan-like fluorescence (TLF) as a rapid in-situ screening tool for assessing faecal contamination risk in groundwater

Faecally contaminated drinking water, a leading cause of diarrhoeal diseases, is currently consumed by an estimated 1.8 million people globally1. Diarrhoeal diseases are a leading cause of death for children under five years old2,3. The United Nations’ Sustainable Development Goal (SDG) 6 calls for universal access to safe drinking water. Groundwater is a major source of drinking water globally1 – in many regions it is the only source of drinking water in the dry season – and faecal contamination of groundwater remains a major concern. There is now strong evidence for the suitability of tryptophan-like fluorescence (TLF) for assessing the risk of faecal contamination in groundwater. TLF provides a robust and rapid in-situ screening tool to enable more rapid monitoring of drinking water quality to help assess progress towards SDG 6.