A new diaper rash spray treatment designed to help “soothe the irritated baby bottom” is doing double-duty helping the environment, using a low global-warming propellant from Honeywell. The new product, Dr. Smith’s Diaper Rash Spray from San Antonio-based therapeutic products company Mission Pharmacal Co., complements the company’s tried-and-true ointment, offering an environmentally friendly and effective alternative to the traditional topical method.