Before revision: Canada According to the Canadian Science Smog Assessment published in 2012, smog is responsible for detrimental effects on human and ecosystem health Rani Sharma, A.
After revision: Asia India 300px|During the autumn and spring months, some 500 million tons of rice and wheat crop residues are burnt, and winds blow from India's north and northwest towards east.Badarinath, K. V. S., Kumar Kharol, S., Rani Sharma, A.