Bincike da aka wallafa a mujallar labaran kiwon lafiya ta Lancet yace, gurbataccen iska wanda ke fili da na cikin wani abu, sun kashe mutane miliyon tara a shekarar 2015, ko kuma sune sanadin daya a cikin kowace mutuwa shida.
A India iska mai guba dake tashi daga kone-kone wasu sanadari tana shiga babban birnin kasar inda miliyoyin mutane ke zaune. Birnin New Delhi ne kan gaba a fadin duniya inda mututne suka fi mutuwa sakamakon gurbatar yanayi.
Wanda ya wallafa bincike yace gurbatar iska na barazana ga yancin bil adama, kamar yancin rayuwa, yancin samun koshin lafiya, yancin kyautatuwar rayuwa da kuma yancin kare yara da marasa galihu.