Tryptophan-like fluorescence as a high-level screening tool for detecting microbial contamination in drinking water

Ward, Jade S.T.; Lapworth, Daniel J. ORCID: https://orcid.org/0000-0001-7838-7960; Read, Daniel S. ORCID: https://orcid.org/0000-0001-8546-5154; Pedley, Steve; Banda, Sembeyawo T.; Monjerezi, Maurice; Gwengweya, Gloria; MacDonald, Alan M. ORCID: https://orcid.org/0000-0001-6636-1499. 2021 Tryptophan-like fluorescence as a high-level screening tool for detecting microbial contamination in drinking water. Science of the Total Environment, 750, 141284. https://doi.org/10.1016/j.scitotenv.2020.141284

Before downloading, please read NORA policies.

Preview

Text (Open Access Paper)
1-s2.0-S0048969720348130-main.pdf - Published Version
Available under License Creative Commons Attribution 4.0.
Download (1MB) | Preview

Official URL: http://dx.doi.org/10.1016/j.scitotenv.2020.141284

Abstract/Summary

Regular monitoring of drinking water quality is vital to identify contamination of potable water supplies. Testing for microbial contamination is important to prevent transmission of waterborne disease, but establishing and maintaining a water quality monitoring programme requires sustained labour, consumables and resources. In low resource settings such as developing countries, this can prove difficult, but measuring microbial contamination is listed as a requirement of reaching the UN's Sustainable Development Goal 6 for water and sanitation. A nine-month water quality monitoring programme was conducted in rural Malawi to assess the suitability of tryptophan-like fluorescence (TLF), an emerging method for rapidly detecting microbial contamination, as a drinking water quality monitoring tool. TLF data was compared with thermotolerant coliforms (TTCs, E. coli) and inorganic hydrochemical parameters. A large (n = 235) temporal dataset was collected from five groundwater drinking water sources, with samples collected once or twice weekly depending on the season. The results show that TLF can indicate a broader contamination risk but is not as sensitive to short term variability when compared to other faecal indicators. This is likely due to a broad association of TLF with elevated DOC concentrations from a range of different sources. Elevated TLF may indicate preferential conditions for the persistence of TTCs and/or E. coli, but not necessarily a public health risk from microbial contamination. TLF is therefore a more precautionary risk indicator than microbial culturing techniques and could prove useful as a high-level screening tool for initial risk assessment. For widespread use of TLF to be successful, standardisation of TLF values associated with different levels of risk is required, however, this study highlights the difficulties of equating TLF thresholds to TTCs or E. coli data because of the influence of DOC/HLF on the TLF signal.

Item Type:	Publication - Article
Digital Object Identifier (DOI):	https://doi.org/10.1016/j.scitotenv.2020.141284
UKCEH and CEH Sections/Science Areas:	Soils and Land Use (Science Area 2017-)
ISSN:	0048-9697
Additional Keywords:	groundwater, water quality, faecal contamination, microbial risk assessment, drinking water, thermotolerant coliforms, GroundwaterBGS, International development, Groundwater and health
NORA Subject Terms:	Hydrology
Date made live:	07 Aug 2020 13:25 +0 (UTC)
URI:	https://nora.nerc.ac.uk/id/eprint/528315

Item Type:

Publication - Article

Digital Object Identifier (DOI):

https://doi.org/10.1016/j.scitotenv.2020.141284

UKCEH and CEH Sections/Science Areas:

Soils and Land Use (Science Area 2017-)

ISSN:

0048-9697

Additional Keywords:

groundwater, water quality, faecal contamination, microbial risk assessment, drinking water, thermotolerant coliforms, GroundwaterBGS, International development, Groundwater and health

NORA Subject Terms:

Hydrology

Date made live:

07 Aug 2020 13:25 +0 (UTC)

URI:

https://nora.nerc.ac.uk/id/eprint/528315