We recently switched gyms, and I have noticed a white haze of chalk dust in the air every time I walk into the new gym to pick my daughter up. The entire gym looks like it is full of fog or cigarette smoke. Somehow this escaped my notice during her evaluation, perhaps because I was so impressed by the other aspects of the program.I found some old threads here suggesting that chalk dust is a respiratory irritant. Is anyone aware of any formal research on the long-term effects of inhaling chalk dust? I haven't been able to find any.