Live Q&A for this topic is Wednesday, April 22, 2020 at 4:00 pm EDT/1:00 pm PDT. Registered attendees can use the link in the Q&A session description to participate.
This research provides a three-tiered testing method to systematically examine the strengths and weaknesses of at-home lead in water test kits. Tiers 1 and 2 evaluate at-home lead in water test kit precision and detection of both high lead (150 ppb dissolved Pb and 50,000 ppb particulate Pb) and dissolved lead (5, 10, and 20 ppb) near the EPA Lead Action Level of 15 ppb. The most precise and sensitive test kit was challenged with various forms of particulate lead, including particulate lead from the pipes of Resident Zero in Flint, Michigan. Results demonstrate that many at-home test kits, including all color change based kits, are not suitable for measuring lead in drinking water, because they indicate either undetectable lead levels when water lead is high, or lead levels much higher than is present. However, binary strip at-home test kits are relatively fast (<15min) and effective screening tools for dissolved lead near or above the EPA Lead Action Level (i.e., 10 or 20 ppb). Further, results demonstrate that digestion using at-home acids (e.g. lemon juice or vinegar) may improve binary strip detection of various forms of particulate lead. Moving forward, this work will provide a roadmap to rigorously determine the strengths and weaknesses of drinking water lead at-home test kits over a wide practically relevant range of conditions.