Recently an international cricket match in the Indian city of Delhi had to be temporarily halted in the middle of the game for an unusual reason. The cause: air pollution levels so high that a top player for India's opponent, Sri Lanka, began vomiting on the field. India has had pollution problems for years, but recently it has gotten significantly worse. Smog was so bad in New Delhi last month the government ordered thousands of schools closed and banned trucks from the road for a week. But