Hello, I'm Mark Lowen and welcome to the documentary from the BBC World Service. We bring people together to share their experiences, and this time we hear from residents of Pakistan's second-largest city, Lahore, and the Indian capital Delhi, as they experience the toxic effects of smog in Pakistan and India.

In recent weeks, dangerous levels of poor air quality has caused authorities to close a number of schools,

universities and businesses in India and Pakistan. We hear from residents and students about what

it's like to live, work and study in a city where going outside could damage your health.

Everything is so grey and bleak. I can't even see the sun anymore.

And not even like five minutes in, my throat starts burning, my eyes are burning.

I can't even go out without having to wear a mask.

Lahore and Delhi often experienced smog at this time of year.

It's caused by a combination of agricultural waste burning, industrial emissions and stagnant weather

that produces a thick, low-lying layer of smoke, gases and chemicals.

But recently, air pollution in both cities has climbed to such high levels that smog

can even be seen from space, and it's causing a lot of concern. Delhi has recorded levels

15 times above the air quality index level, or AQI, that the World Health Organization considers

satisfactory for breathing. Meanwhile, poor air quality in Lahore in neighbouring Pakistan

has also reached record levels and toxic air is disrupting everyday life.

It used to be known as the city of gardens,

but now many of its parks are closed.

Here's how the smog is affecting some of the people that live and work there,

starting with rickshaw driver Asif Ali.

We are compelled to go out because we have children.

If we stay home, what will we do?

We have to earn our livelihood.

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