We used to use TSP all the time at the silk screen shop in the 80’s. I was under the impression one could no longer get it, thanks to the tree huggers. I haven’t noticed it in the paint dept. of the hardware stores for a long time...but then again, I wasn’t lookin’. : )
That's because they changed the old orange box that was so familiar. You have to ask for it, you'd never recognize it now.
TSP and other phosphates pass through our laundry and dishwashers, through the waste water system, and into the ecosystem. TSP and related phosphates are blamed for algae blooms that create dead zones as they die, pulling oxygen from the water. Thus the chemicals were removed from our cleaning supplies in the name of helping wild-life.