Delhi on November 8, 2017. Delhi shut all primary schools on November 8 as pollution levels hit nearly 30 times the World Health Organization safe level, prompting doctors in the Indian capital to warn of a public health emergency. Dense grey smog shrouded the roads of the world's most polluted capital, where many pedestrians and bikers wore masks or covered their mouths with handkerchiefs and scarves.
“Childhood and adolescent noise pollution exposure could increase anxiety by increasing stress and disrupting sleep, with high noise potentially leading to chronic physiological arousal and disruption to endocrinology,” they added. “Noise pollution could also impact cognition, which could increase anxiety by impacting concentration during school years. It was interesting that noise pollution was associated with anxiety but not with psychotic experiences or depression.