In-situ tryptophan-like fluorescence: A real-time indicator of faecal contamination in drinking water supplies

WATER RESEARCH

卷:81

Article

Sorensen, J. P. R.¹  Lapworth, D. J.¹  Marchant, B. P.²  Nkhuwa, D. C. W.³  Pedley, S.⁴  Stuart, M. E.¹  Bell, R. A.²  Chirwa, M.³  Kabika, J.³  Liemisa, M.⁵  Chibesa, M.⁵ 

[1] British Geol Survey, Wallingford OX10 8BB, Oxon, England

[2] British Geol Survey, Nottingham NG12 5GG, England

[3] Univ Zambia, Lusaka, Zambia

[4] Univ Surrey, Robens Ctr Publ & Environm Hlth, Guildford GU2 7XH, Surrey, England

[5] Lukanga Water & Sewerage Co Ltd, Kabwe, Zambia

关键词: Tryptophan-like;    Fluorescence spectrophotometry;    Thermotolerant coliforms;    Pathogens;    Africa;    Waste water;   

DOI  :  10.1016/j.watres.2015.05.035

来源: Elsevier

【 摘 要 】

Enteric pathogens are typically inferred from the presence of surrogate indicator organisms such as thermotolerant (faecal) coliforms (TTCs). The analysis of TTCs requires time-consuming incubation in suitable laboratories, which can limit sampling resolution, particularly during critical pollution events. Here, we demonstrate the use of in-situ fluorimeters targeting tryptophan-like compounds as a rapid, reagentless indicator of TTCs in groundwater-derived potable water supplies in Africa. A range of other common indicators of TTCs were also determined including nitrate, turbidity, and sanitary risk survey scores. Sampling was conducted during both the dry and wet seasons to investigate seasonality. Tryptophan-like fluorescence was the most effective predictor of both presence/absence and number of TTCs during both seasons. Seasonal changes in tryptophan-like fluorescence in deeper supplies suggest it is transported more efficiently through the aquifer than TTCs. Moreover, the perennial elevated concentrations in some wells suggest it is more resilient than TTCs in groundwater. Therefore tryptophan-like fluorescence could also be a better indicator of some smaller, more easily transported, and long-lived, pathogenic enteric viruses. These sensors have the potential to be included in real-time pollution alert systems for drinking water supplies throughout the world, as well as for mapping enteric pathogen risks in developing regions. (C) 2015 British Geological Survey (a component body of NERC). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

【 授权许可】

Free