Water is the essence of life, yet millions worldwide still lack access to safe drinking water. Among the numerous challenges in achieving universal water safety, the time-consuming and costly nature of traditional water quality testing remains a significant barrier—particularly in remote areas where sample collection, transportation, laboratory analysis, and result interpretation consume substantial resources.
The World Health Organization (WHO) and UNICEF are collaborating to revolutionize this process through the development and deployment of portable water testing tools. These innovations aim to make on-site water quality assessment faster, more affordable, and easier to implement, bringing the world closer to achieving global water safety goals.
To ensure the reliability of portable testing devices, WHO established a technical advisory group in 2019 and developed a comprehensive evaluation protocol. The assessment focuses on tools designed to detect Escherichia coli (E. coli), a key indicator of fecal contamination in water.
The evaluated tools fall into two categories based on their quantification methods: colony counting systems and suspension-based measurements that use Most Probable Number (MPN) statistical methods.
Most quantitative portable tools in the evaluation employ colony counting techniques. The majority use membrane filtration with 100 mL samples, though two products analyze 1 mL samples without filtration. One innovative system utilizes a gel medium that enables direct colony counting without membrane filtration.
Participating colony counting systems include:
This category includes tools that partition samples into multiple subsamples using proprietary compartments or wells, then calculate contamination levels through standard statistical MPN methods. For instance, the Fluidion ALERT LAB measures optical changes in absorbance and fluorescence over time to determine contamination levels.
Other suspension-based tools use 10 or 100 mL samples to indicate E. coli presence. For quantitative results, 100 mL samples are divided into 96 subsamples of approximately 1 mL each in deep-well plates. The MPN value is calculated based on positive well counts after incubation.
Participating suspension-based systems include:
In collaboration with WHO, UNICEF launched the Rapid Water Testing project to accelerate the development of next-generation field testing tools. The initiative established a Target Product Profile (TPP) outlining the ideal characteristics for field testing devices, first published in September 2016 and updated in December 2019 and November 2022.
In May 2022, UNICEF partnered with Nigeria's Federal Ministry of Water Resources to field-test two new rapid water testing methods in Abuja's rural communities. The week-long evaluation assessed various water sources including boreholes, river water, and treatment facilities from the Abuja Water Board.
One prototype device provided total coliform and E. coli results within one hour, while another delivered general biological readings in just 15 minutes. The field tests provided developers with crucial feedback about usability in resource-limited settings and practical implementation challenges.
UNICEF and WHO continue to collaborate with developers and industry partners to establish an evaluation framework for these products. They've partnered with AOAC International to develop performance testing methods for innovative products that don't rely on incubation, colony counting, or MPN analysis.
Through these concerted efforts, portable water testing tools are poised to play an increasingly vital role in achieving global safe water objectives, particularly in underserved communities where traditional laboratory testing remains impractical.
Water is the essence of life, yet millions worldwide still lack access to safe drinking water. Among the numerous challenges in achieving universal water safety, the time-consuming and costly nature of traditional water quality testing remains a significant barrier—particularly in remote areas where sample collection, transportation, laboratory analysis, and result interpretation consume substantial resources.
The World Health Organization (WHO) and UNICEF are collaborating to revolutionize this process through the development and deployment of portable water testing tools. These innovations aim to make on-site water quality assessment faster, more affordable, and easier to implement, bringing the world closer to achieving global water safety goals.
To ensure the reliability of portable testing devices, WHO established a technical advisory group in 2019 and developed a comprehensive evaluation protocol. The assessment focuses on tools designed to detect Escherichia coli (E. coli), a key indicator of fecal contamination in water.
The evaluated tools fall into two categories based on their quantification methods: colony counting systems and suspension-based measurements that use Most Probable Number (MPN) statistical methods.
Most quantitative portable tools in the evaluation employ colony counting techniques. The majority use membrane filtration with 100 mL samples, though two products analyze 1 mL samples without filtration. One innovative system utilizes a gel medium that enables direct colony counting without membrane filtration.
Participating colony counting systems include:
This category includes tools that partition samples into multiple subsamples using proprietary compartments or wells, then calculate contamination levels through standard statistical MPN methods. For instance, the Fluidion ALERT LAB measures optical changes in absorbance and fluorescence over time to determine contamination levels.
Other suspension-based tools use 10 or 100 mL samples to indicate E. coli presence. For quantitative results, 100 mL samples are divided into 96 subsamples of approximately 1 mL each in deep-well plates. The MPN value is calculated based on positive well counts after incubation.
Participating suspension-based systems include:
In collaboration with WHO, UNICEF launched the Rapid Water Testing project to accelerate the development of next-generation field testing tools. The initiative established a Target Product Profile (TPP) outlining the ideal characteristics for field testing devices, first published in September 2016 and updated in December 2019 and November 2022.
In May 2022, UNICEF partnered with Nigeria's Federal Ministry of Water Resources to field-test two new rapid water testing methods in Abuja's rural communities. The week-long evaluation assessed various water sources including boreholes, river water, and treatment facilities from the Abuja Water Board.
One prototype device provided total coliform and E. coli results within one hour, while another delivered general biological readings in just 15 minutes. The field tests provided developers with crucial feedback about usability in resource-limited settings and practical implementation challenges.
UNICEF and WHO continue to collaborate with developers and industry partners to establish an evaluation framework for these products. They've partnered with AOAC International to develop performance testing methods for innovative products that don't rely on incubation, colony counting, or MPN analysis.
Through these concerted efforts, portable water testing tools are poised to play an increasingly vital role in achieving global safe water objectives, particularly in underserved communities where traditional laboratory testing remains impractical.
