Effects of air pollution on passerine birds and small mammals

The effects produced by emissions from coal-fired power plants, including mainly SO2, NOx and particulates, on natural populations and caged specimens of birds and small mammals were studied. The field-captured species used to evaluate these effects were passerine birds: Parus major (coal tit) and Emberiza cia (rock bunting), and the rodent Apodemus sylvaticus (wood mouse). In parallel to this study on animals captured in the field, we used other animals, Mus musculus (house mouse) and Carduelis carduelis (goldfinch) which were placed in cages near the source of pollution. Some of the animals were killed and their tracheas were removed and prepared for conventional optic studies (1000x) and electron microscopy (TEM and SEM). The results show that atmospheric air pollutants from coal-fired power plants produce alterations in the tracheal epithelium. In passerine birds, an increase in the mucus which covers the tracheal epithelium, shortening of the cilia, and increase in the number of secretory granules and vesicles were observed. In mammals, variation of the uniformity of the pseudostratified epithelium with a wide stratum of mucus, shortening of the cilia, and increase in the number of secretory granules were observed.