How do you know what's actually being removed from your water when using a 3M commercial water filter?

Commercial Water Filters - https://bit.ly/39bXyBx
Residential Water Filters - https://bit.ly/3sQ3CHu
Water Filter Buying Guide - https://bit.ly/39bwMca
3M Water Filter Buying Guide - https://bit.ly/3a24Ir9
3M Commercial Water Filters - https://bit.ly/3iF6jXC