A friend of mine from school who has a kitty said she heard on the news this weekend that clumping clay litter is very hazardous to both our kitties and us. She said there were 3 ingredients to watch out for in litter...sodium bentonite, quartz silica, and I don't remember the 3rd. Of course, litter containers don't list their ingredients. I have not heard this news, but found some info online this afteroon about it. Apparently the sodium bentonite expands and becomes "cement" inside cats if the litter gets inside them (ex. licking their paws) and the dust from litter can coat their lungs and cause respiratory probs in cats. The quartz silica is apparently a known carcinogen for both humans and cats. Has anyone else heard this most recent news? Should I be concerned? I use Tidy Cats Long Lasting Odor Control For Mulitple Cats. I'm not sure if it's clumping litter or not, it doesn't say it is on the bag. Anyone recommend an alternative type of litter?