Those are Trane Air Conditioning lies, because their refrigerant (R-123) still depletes ozone. The only knock against R-134a is that it results in slightly decreased efficiency. Through some convoluted logic, one can postulate that adds to the "Greenhouse Effect" because more energy must be produced at power plants to cover that reduced efficiency, thereby resulting in a poorer environment. A huge stretch, at best.

R-134a has no direct effect on pollution. It's so safe for breathing, it's used for propellent in asthma inhalers.