Thirty pollutants are identified that are potentially harmful contaminants. Available information about them has been summarized in a series of reports describing their sources, distribution, effects, and control technology for their abatement. The mild symptoms of mercury intoxication are psychopathological in nature and can present serious problems in diagnosing the cause. The mining and refining of mercury and its use in laboratory applications can be serious sources of air pollution. Methods of controlling mercury air pollution are available but may not be adequately employed. A bibliography is included.