Pollution has been hitting dangerous levels across New Delhi and other parts of northern India this month, in a sharp deterioration from October when people breathed the cleanest air in four years. Devotees were seen taking a dip in the Yamuna river near Kalindi Kunj in Delhi on the first day of Chhath puja today as alarming white, toxic foam covered the river. The water of the river, considered holy, is barely visible in grim visuals shared by news agency ANI.