Inter Press Service: Olivia González has been a schoolteacher for 30 years in Cerro Navia, one of the districts in the Chilean capital with the highest concentration of air pollution between April and August. A first-hand witness to its effects on health, she is pessimistic about the air she’ll breathe this coming southern hemisphere winter. “Every year, the students in the municipal school where I work come down with many headaches and respiratory problems. As a result, they are constantly missing class …