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Abstract. Confined animal feeding operations generate air pollution that can affect food animal welfare, including animal health, productivity, and behavior. This paper reviews scientific research associated with agricultural air pollution and food animal health and welfare based on 167 journal research publications. Scientific studies in this area started in the 1930s and have continued for nine decades. The number of publications, which reflected research activities, in each decade increased dramatically since the 1960s and reached 41 in the 2010s. Twenty-two countries in Asia, Africa, Australia, Europe, and North America have contributed to the research. About half of the studies were conducted in the U.S. and U.K. On-farm scientific discoveries on air toxicity that resulted in animal death or injury were all from observational studies. About 80% of the reported studies have been designed experimentally and conducted mostly under laboratory conditions. Ammonia (NH₃) was the primary pollutant reported in about 70% of the studies, followed by dust, hydrogen sulfide (H₂S), carbon dioxide (CO₂), bacteria, endotoxin, sulfur dioxide (SO₂), odor, and nitrous oxide (N₂O). Approximately 23% of publications reported multiple pollutants in the same study, such as more than two types of gases, or one or few types of gases plus dust or other pollutants. Different animal species and egg/embryo were subjects of the nine-decade research. The most intensively studied animal species were poultry (broiler, chicken, hen, turkey, and duck) in about 47% of the journal publications and pig (41%), followed by cattle, sheep and goat, egg and embryo, and donkey.  Compared with air pollution from agriculture in general, scientific investigations into air pollution-related animal health and welfare are still relatively limited.