BENGALURU: India may have taken the term "filthy rich" literally. Indian cities' growth remains tied to polluting fossil-fuel use and consequent pollution while China and several other countries have pulled ahead on cleaner urbanisation, according to a study in Nature Cities in which researchers analysed 5,435 cities worldwide between 2019 and 2024 using satellite-based nitrogen dioxide data and GDP estimates.Of the 390 cities globally classified as 'dirtier and richer', where economic growth coincided with rising pollution, 138, or nearly 35.4%, were in India. While metros such as Delhi, Mumbai and Kolkata showed cleaner growth trends, the study says many Indian…