I don't think its just because of India. I regularly travel on ring road and have seen thick clouds of black smoke from burning fields and brick kilns many times. Also this Dawn article covers how this smog is our own fault.
Snippets from the article:
While the majority of fires are indeed detected on the Indian side, it can also be observed that similar burning occurs in May every year, at the end of the Rabi crop season.
The claim that crop burning in India causes smog in Lahore is not only without evidence, but it is statistically false with a very small correlation coefficient, illustrating the lack of scientific understanding required to deal with the crisis.
In the past, a similar evidence-gathering exercise was conducted with the help of the World Bank, which outlined in detail policy actions needed to curtail the worsening air quality in Pakistan.
Both of these studies, instead of concluding crop fires as the cause, point towards the transport sector as the biggest culprit behind air pollution.
While both studies had different methodologies and study areas, they rank agricultural sources as the third largest in proportion (In the World Bank study, ‘Other’ includes agriculture).
