Congress and a revitalized Environmental Protection Agency have two new bodies of evidence to buttress strong anti-pollution legislation and enforcement. They are reports by the Conservation Foundation and the National Science Foundation that reach the same conclusion: Despite contentions to the contrary, American industries do not tend to flee from areas that are tough on pollution to ''pollution havens.'' Reasons for moving do tend to be labor, markets, and raw materials.
Efforts are under way to weaken present federal requirements that air quality standards be set to protect public health without consideration of economic factors. The new reports suggest that one of these supposed factors - the flight of industry from environmental regulation - is not much of a factor after all.