Step 1: Establish the connection between tanning and chromium.
Chromium, especially hexavalent chromium, is a key component in leather tanning. Incorrect disposal of tannery waste significantly pollutes soil and water with chromium.
Step 2: Locate significant leather tanning centers in India.
Major Indian leather industry hubs include Kanpur in Uttar Pradesh and a large concentration in Tamil Nadu, encompassing cities such as Vellore, Ambur, and Dindigul.
Step 3: Assess the states most impacted by pollution from this industry.
Though Kanpur (Uttar Pradesh) also faces substantial pollution, Tamil Nadu is the state with the highest density of tanneries and a well-documented history of severe chromium contamination, particularly in the Palar river basin, making it the primary example of this environmental problem in India.