Just think, that glass of nice cool water out of your tap could've come fresh from Zek's bladder. Still, look on the bright side, all that second-hand oestrogen will probably take the edge of any impending male-pattern baldness. He's probably on birth control pills too (it's best not to ask) so you'll likely be chugging on
ethinyl estradiol as well. Yum Yum. Get it down you son. It'll put hairs on your ch... oh, no... it won't.
I jest of course. Reverse osmosis and UV light treatment should filter out unwanted chemicals and destroy pathogens in reclaimed water. Or at the very least reduce their occurence down to 'acceptable' levels, i.e. no worse than water from more traditional sources. Distillation would achieve the same results but this is a very expensive and energy intensive process when used on an industrial scale.