dangerous levels of toxic chemicals have been detected in the ambient air in and around Tamil Nadu's Cuddalore industrial estate. Residents of the area have constantly complained about widespread air and water pollution and related health problems, particularly among children. The industrial area comprises several chemicals manufacturing units. Residents in and around the area often complain about strong chemical odour. But the Tamil Nadu Pollution Control Board considers odour a mere nuisance and not an indicator of chemical pollution.

Ambient air samples from the area were collected and tested by the State Industries Promotion Corporation of Tamil Nadu (sipcot) during March 2004 to June 2004 . sipcot's Area Community Environment Monitors (sacem) collected these samples during five instances of strong chemical odour and detected 22 toxic chemicals in them. Thirteen of these are used as raw materials in one or more industrial units in the area and eight are known to be carcinogenic. In its report Gas Trouble, sacem has demanded continuous and long-term monitoring of emissions in the area, in addition to corrective action, to bring the levels of toxic gases below detection limits. Nearly 20,000 people live in the potential impact zone, according to sipcot's estimate.

sacem used a community-based air-sampling device called the "Bucket' to capture the air samples (See [2]