NDMA Formation from Gaskets Used In Water Storage Tanks

摘要

Elevated concentrations of N-nitrosodimethylamine (NDMA) were detected in a distribution system during routine monitoring. The high concentrations were localized, and a temporary storage tank was suspected to be the source of the problem. Samples of the gaskets used in the construction of the temporary tank were gathered and subjected to bench-scale tests. These tests demonstrated that the gaskets, when exposed to system water, did produce NDMA as well as other nitrosamines. Scaling up the surface-area-to-volume ratios from bench-scale to full-scale, the concentrations of NDMA measured in the bench-scale tests were not high enough to account for all of the NDMA measured in the full-scale tank, assuming complete mixing.