"The data shows that the city is the noisiest in the world and poses a serious threat to one's ears, brain and heart. Almost every area in Mumbai has high sound levels. The administration should have the strong will to implement a stringent enforcement mechanism," said environmental activist Sumaira Abdulali.

Air pollution has serious health implications, including strokes and heart attacks, and in extreme cases lung cancer, said Dr Altaf Patel, former professor at J J Hospital and presently a director of medicine at Jaslok Hospital. "The more you breathe fresh air, the more is your life expectancy," he said. "As for water pollution, especially by heavy metals, it can lead to heart attacks and cancer, besides causing hypertension and mental disturbance."