My vet told me to avoid pine based litters (like feline pine) for my asthmatic cat because pine can be a problematic allergen. Also, I've read that feline pine breaks down into sawdust after it gets wet, so I don't imagine it's a good idea as far as dust goes.
I have used Yesterday's News, and it also breaks down after getting wet. You say you don't like it; have you tried it in a sifting box? Not a regular sifting box, but one with space between the grate and the real bottom of the pan. You put the YN (or feline pine) on top, and when it gets wet with urine and then dries, it breaks up and sifts to the bottom.
I've made a different choice, though; have you heard of The Breeze from Tidy Cats? It's inert pellets (unfortunately, I have been completely unable to get any information about the contents of the pellets) over a grate that drains into a tray with a urine pad. There are small pieces of sand/dust that come from the pellets in the pellet bag, but they quickly fall to the bottom and don't appear to ever be airborne when cats are using the box. It's not the cheapest solution, and it took a long transition to get my cats used to, but they seem to enjoy it and my asthmatic cat hasn't coughed in months! (She also had a corticosteroid shot, but she got that some time ago. I've been using Yesterday's News and transitioning to the Breeze in this time period.)Here's
the official page.
You should be able to get the box and the refills from WalMart, but I don't live by one so ordered mine from amazon.com.
When/if you buy/order them, be sure to buy an extra bag of pellets at the same time. They give you one bag, which is enough to go into the Breeze, but just barely. It's a system that relies on a fairly thin layer of pellets to allow the urine to easily flow through, and that, in addition to the fact that it's pellets, makes it hard for cats to adjust. So it helps to have at least that much in the box, and you'll have to sprinkle some pellets in with your old litter to help you cats figure out what the pellets are for. You may have to mix a lot of Breeze litter into your old litter, increasing the proportion slowly, in order to get your cats to transition.
There have been, by my count, three threads on this forum about the breezeThe first thread, from a skeptical early adopter. Includes pictures at the top.The second one, started by a big fan. Includes pictures, on page 2.The most recent one, started by a hopeful person who isn't having a lot of luck with the transition.