IPD - the process of heating and extruding the pine litter really cooks out the phenols and volatile oils. When you bust a bag open, it has a faint, faint pine aroma, but nothing like pine needles or fresh-milled pine wood. Because the cats are in and out, and the dissolved sawdust filters to the bottom where they are less likely to track it and ingest it, I'm comfortable with it. Additionally, with all my searching I wasn't able to find any hard evidence for heat-treated pine litter toxicity. For things like Pine-sol, sure - don't use that shit on your floors! - but not the heat-treated litters.
Sorry to hear about your dust allergies. Strangely enough, we originally started looking for new and better litters because my fat white atopic cat started getting sores between his pads from the wheat litter we were using.
arebelspy and daizy744 - I wish I could compost it! I live in a 700sf apartment with no dirt anywhere close. I have windowboxes :) The nice thing about the pine is that you can flush it in small amounts, though I generally chuck it. Little cat turds can be flushed even if they have pellets stuck to them, which isn't true for clay litters. If I could I'd compost in a heartbeat, though. The general rule is equal parts green matter and brown matter like sawdust, etc.
Also, for my post I was using the price I found online. At my local feed store, a 40lb bag goes for more like 5 or 6 dollars. So that's in the range of 60-72 dollars a year. And seriously, you cannot beat the odor control if you sift regularly. I tried about five kinds of litter before I found one that didn't PISS ME OFF every time I opened the front door coming home. GROSS!