India has become one of the world's top three countries with the worst air quality, and its capital is the world's most polluted city. According to the World Air Quality Project, the air quality index above 150 is considered unhealthy, but the levels in New Delhi have well above 300, the highest indicator for hazardous air quality. In an effort to reduce the dangerous levels, the authorities have restricted vehicle use in the city. VOA's Zlatica Hoke has more.