Why is everything you write, underlined?
Confused me, I thought it was a link to a worksheet of the data you'd collected, or something.
Because by underling the entire question, he covers the fact that he threw a link in.
He's a spammer
Just the durability issue, I think, puts cast well over acrylic. The tub in my bathroom is 109 years old. Try that with acrylic! It's been re-enameled (a few times, I think, and it's due to get re-enameled again); but it's the original tub. You'd have to strip the plaster off my bathroom walls, then either tear open a load-bearing wall, or gut out my whole kitchen, to replace it; there's no indication that any of those walls have ever been taken out.
Cast iron is recyclable, and often made from recycled scrap iron. Whereas acrylic, is made from petroleum, and ends up in a landfill.
Iron is non-toxic, and it breaks down completely; it rusts slowly, but it does rust. The enamel coating on a cast tub is slightly toxic, and doesn't break down... But it's no contest, compared to the acrylic & glass in a plastic tub. I used to work in a boatyard, so I know a bit about resins, and let me tell you, acrylic resin is nasty stuff. As for fiberglass, it never breaks down, and we use it so much that they've found traces of it on the peak of Mt Everest. It's not toxic, per se, but it is a respiratory irritant.
This is just off the top of my head, and I've never studied it in detail; but I don't see how they could rate anywhere close to each other. Cast is way greener than acrylic.