A bibliographic database of literature in the field of occupational safety and health. About 160 current, English language technical journals provide approximately 35 percent of the additions to NIOSHTIC annually. Retrospective information, some of which is from the 19th century, is also acquired and entered. Because NIOSH examines all aspects of adverse effects experienced by workers, much of the information contained in NIOSHTIC has been selected from sources that do not have a primary occupational safety and health orientation. Types of information selected include behavioral sciences; biochemistry, physiology, and metabolism; toxicology; pathology and histology; chemistry; control technology; education and training; epidemiological studies of diseases and disorders; ergonomics; health physics; occupational medicine; safety; and hazardous waste.