Hi all…a just published review article on the risk of engineered and incidental nanoparticles in drinking water concludes risks to human health are low. The authors have examined a substantial number of articles and justify this by stating that “engineered nanoparticles (ENPs) are currently orders of magnitude less common than NNPs in waters that flow into drinking water treatment plants. Because such plants are designed to remove small-sized NNPs, they are also very good at removing ENPs. Consequently, ENP concentrations in tap water are extremely low and pose low risk during ingestion.” The one caveat is that ‘incidental’ nanoparticles may be released from distribution system or in-home pipes/plumbing and that future research should focus on these.

They draw a parallel with pharmaceuticals stating that “nearly two decades of intensive data collection on low-level pharmaceutical occurrence at DWTPs has allowed water professionals to better communicate with the public, pre-empt regulations due to the lack of data, bring together aquatic ecosystem and human health communities, and provide tools for individual DWTPs to install technologies as needed to address concerns regarding this class of chemical pollutants.”

The article is a good source of science-based information to assist drinking water providers and regulators with responding to public concerns. I don’t think that it is ‘open access’ though.

Bill


Low risk posed by engineered and incidental nanoparticles in drinking water

Paul Westerhoff, Ariel Atkinson, John Fortner, Michael S. Wong, Julie Zimmerman, Jorge Gardea-Torresdey, James Ranville & Pierre Herckes
Nature Nanotechnology, Volume 13, pages 661–669 (2018) http://www.nature.com/articles/s41565-018-0217-9

ABSTRACT

“Natural nanoparticles (NNPs) in rivers, lakes, oceans and ground water predate humans, but engineered nanoparticles (ENPs) are emerging as potential pollutants due to increasing regulatory and public perception concerns. This Review contrasts the sources, composition and potential occurrence of NNPs (for example, two-dimensional clays, multifunctional viruses and metal oxides) and ENPs in surface water, after centralized drinking water treatment, and in tap water. While analytical detection challenges exist, ENPs are currently orders of magnitude less common than NNPs in waters that flow into drinking water treatment plants. Because such plants are designed to remove small-sized NNPs, they are also very good at removing ENPs. Consequently, ENP concentrations in tap water are extremely low and pose low risk during ingestion. However, after leaving drinking water treatment plants, corrosion by-products released from distribution pipes or in-home premise plumbing can release incidental nanoparticles into tap water. The occurrence and toxicity of incidental nanoparticles, rather than ENPs, should therefore be the focus of future research.”