New York Times: The children Karolina Zolna knows huff and puff after a few minutes of exercise. Two years ago, her infant daughter spent four months in the hospital with pneumonia. The doctors did not identify a cause, but to Ms. Zolna, the reason for the babys illness was obvious. She blames the pollution that hangs heavy in the air of her gray hometown in Polands coal heartland, Silesia. In the still-chilly early days of spring, thick smoke wafted from most of the chimneys in Myslowice, wreathing the town...