||Bowden DH. Cell turnover in the lung. Am Rev Respir Dis. 1983 Aug128(2 Pt 2):S46-8. DOI: 10.1164/arrd.1983.128.2P2.S46 p.S47 right column bottom paragraph & p.S48 left column top paragraphPubMed ID6881708
||6) Bertalanffy FD, Leblond CP. The continuous renewal of the two types of alveolar cells in the lung of the rat. Anat Rec 1953 115:515-36 (7) Bowden DH, Davies E, Wyatt JP. Cytodynamics of pulmonary alveolar cells in the mouse. Arch Pathol 1968 86:666-70PubMed ID13031142, 5701640
||P.S47 right column bottom paragraph to p.S48 left column top paragraph: "Alveolar Macrophages: The turnover time of alveolar macrophages has been estimated to be approximately 7 days (primary sources) (table 3). To be precise, this is not a true turnover time but the average time the macrophage spends in the alveolus. Alveolar macrophages are temporary residents derived from the monocytic compartment of the blood and the interstitial compartment of the lung, they are destined to be eliminated through the tracheobronchial tree. As cells are in transit it is appropriate to speak of a transit or sojourn time. Usually, this is about 7 days (primary sources 6, 7, ref 21), and in response to an inhaled particulate load this figure may be halved because of a coordinated acceleration of the delivery and elimination of these phagocytic cells to and from the alveoli (ref 21)."