I've used quartz sand for years without a problem. I've had problems with things that had baking soda in them and with chinchilla dust but not handy sand. I even did an entire desert setup in one plastic storage container connected to others for food and cardboard destruction. My pairs produced offspring for 3-5 years with 20-30lbs of sand available and often buried their dirty bedding in parts of it daily which I would sift weekly with an aquarium net to remove the nonsand items and clumpy peed on parts. Never saw a respiratory problem. Healthier than putting them in a room with a couple small birds. We ended up with respiratory problems from parakeets and humans are known to have problems even with a single pet bird so I put silica dust at the bottom of my things to worry about list. Definitely below pine dust and volatile oils which I fill my 20 sq ft of indoor rabbit cages with. Even put it below raw oat dust. Ugh that stuff would have me coughing black for a week after we shoveled the horse feed every fall in to barrels. That's probably where my mild asthma comes from.