A six-week experiment to track the long distance transport of airborne pollutants from Canadian and United States sources started early in September.

Some 200 kilograms of an inert, colorless, odorless and non-toxic tracer gas (perfluoro-monomethyl-cyclohexane) were to be released on three occasions from Sudbury, Ontario and Dayton, Ohio. Releases were to be about one week apart, depending on weather conditions.

Seven aircraft and 85 ground sampling stations would track the tracer for 1,000 kilometres across eastern North America.

The release sites are near two main sources of airborne pollution and are thought to contribute significantly to acid rain.

CAPTEX is expected to cost $2 to $3 million. Canada will contribute about 10 percent.

Canadian agencies participating include Environment Canada, the Ontario and Quebec environment ministries and the National Research Council. In the United States, the Department of Energy, The National Oceanic and Atmospheric Administration, the Environmental Protection Agency and the Electric Power Research Institute are involved.