Interestingly, these particles are present even in the weir box, which is the final point before discharge to the municipal wastewater stream. These particles have a mean diameter of 54 nm (SD ± 18 nm) and a spherical shape, making them similar in both size and shape to other samples as well as to CMP slurries used in the processes. Size distribution of these particles is shown in Fig. 5. EDX data indicates that these