New Delhi West Bengal has the highest number of red category industries causing high pollution, followed by Maharashtra and Tamil Nadu, while 43 industrial clusters have been identified as "critically polluted", the Lok Sabha was informed today.

Environment and Forest Minister Jayanthi Natarajan said during Question Hour that the Central Pollution Control Board (CPCB) and IIT-Delhi had conducted a survey based on Comprehensive Environmental Pollution Index (CEPI) for assessment of pollution load of industrial areas.