cant answer definitely re using recycled pooey water...am guessing if you put the wash water down the sink and just let the rinse water go on the garden itd be ok!
I have a top loader and we use Green Care laundry liquid (there is also a front loader version now so make sure u get the right one), I buy the big packs from Big W cause is cheaper. we use all the wash water (no kids yet so our clothes arent exactly really dirty lol) on the garden, mainly on our plum tree and a couple of other trees and none have died from it!