In this article from Issue 15 of the Analytix Reporter, it is shown that while a quality drinking water standard must always be maintained, regulations by USEPA, EU, and others have increasingly allowed for more method flexibility in recent years to allow also rapid photometric tests, for example.
Contaminated water is a threat to human health and the environment. As a result, national and international regulatory agencies like the U.S. Environmental Protection Agency (USEPA), World Health Organization (WHO), EU, and other regulators have set official drinking water testing methods and wastewater testing methods. For the analysis of drinking water, these methods must be used to assure a certain quality of the results and to ensure a benchmark of health and safety.
While a quality standard must always be maintained, regulations have increasingly allowed for more method flexibility in recent years. For example, the USEPA criteria for the recognition of slightly modified methods were pioneers in terms of simplifications. This paved the way to use test kits with the same chemistry like in official water testing methods. The revisions of the EU drinking water directives are also pursuing a similar approach. In the latest update of December 2020 [EU Directive 2020/2184], the measurement of uncertainty in conjunction with the limit of detection was defined as the criteria for method applicability. This means that any method can now be used in principle for the analysis, provided it meets the criteria. This also applies to the use of alternative methods like rapid tests.
To provide more convenient, while still reliable methods for users, rapid test methods following recognized standards (ISO, USEPA, and others) were developed. Respective certifications like ISO accordance or equivalency to EPA methods assure users that the ready-to-use test kits deliver comparable results so they can be used to comply with national regulations. These methods offer several additional benefits. One notable advantage is the reduced use of chemicals and sample volumes, resulting in decreased waste generation and enhanced user safety.
*The life science business of Merck operates as MilliporeSigma in the U.S. and Canada.