title: Before the first breath: prenatal exposures to air pollution and lung development.
abstract: Various environmental contaminants are known to impair the growth trajectories of major organs, indirectly (gestational exposure) or directly (postnatal exposure). Evidence associates pre-gestational and gestational exposure to air pollutants with adverse birth outcomes (e.g., low birth weight, prematurity) and with a wide range of diseases in childhood and later in life. In this review, we explore the way that pre-gestational and gestational exposure to air pollution affects lung development. We present results in topics underlining epidemiological and toxicological evidence. We also provide a summary of the biological mechanisms by which air pollution exposure possibly leads to adverse respiratory outcomes. We conclude that gestational and early life exposure to air pollutants are linked to alterations in lung development and function and to other negative respiratory conditions in childhood (wheezing, asthma) that may last into adulthood. Plausible mechanisms encompass changes in maternal physiology (e.g., hypoxia, oxidative stress and inflammation) and DNA alterations in the fetus. Evidence for pre-gestational and gestational effects on the lung is scarce compared with that on early life exposure and further studies are needed. However, the suggested mechanisms are credible and the evidence of pre-gestational and gestational air pollution exposure is robust for adverse birth outcomes. Air pollutants might change lung developmental trajectories of the unborn child predisposing it to diseases later in life highlighting the urgent need for controls on urban air pollution levels worldwide.
authors.affiliation: Laboratory of Environmental Air Pollution, LIM05, Department of Pathology, University of Sao Paulo School of Medicine, Av. Dr. Arnaldo 455 (1st floor, Room 1220), 01246-903, Sao Paulo, SP, Brazil. verasine@usp.br.|Department of Surgery, Sector of Anatomy, Faculty of Veterinary Medicine and Animal Sciences, University of Sao Paulo, Sao Paulo, Brazil. verasine@usp.br.
authors.forename: Mariana Matera
authors.initials: MM
authors.lastname: Veras
authors.affiliation: Laboratory of Environmental Air Pollution, LIM05, Department of Pathology, University of Sao Paulo School of Medicine, Av. Dr. Arnaldo 455 (1st floor, Room 1220), 01246-903, Sao Paulo, SP, Brazil.
authors.forename: Nilmara
authors.initials: N
authors.lastname: de Oliveira Alves
authors.affiliation: Laboratory of Environmental Air Pollution, LIM05, Department of Pathology, University of Sao Paulo School of Medicine, Av. Dr. Arnaldo 455 (1st floor, Room 1220), 01246-903, Sao Paulo, SP, Brazil.|Advanced Study Institute, University of Sao Paulo (IEA-USP), Sao Paulo, Brazil.
authors.forename: Lais
authors.initials: L
authors.lastname: Fajersztajn
authors.affiliation: Laboratory of Environmental Air Pollution, LIM05, Department of Pathology, University of Sao Paulo School of Medicine, Av. Dr. Arnaldo 455 (1st floor, Room 1220), 01246-903, Sao Paulo, SP, Brazil.|Advanced Study Institute, University of Sao Paulo (IEA-USP), Sao Paulo, Brazil.
authors.forename: Paulo
authors.initials: P
authors.lastname: Saldiva
mesh_terms: D000397:Air Pollution / Q000009:adverse effects*; D000818:Animals; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D008168:Lung / Q000196:embryology*; D011247:Pregnancy; D047928:Premature Birth; D011297:Prenatal Exposure Delayed Effects / Q000453:epidemiology / Q000473:pathology* / Q000503:physiopathology*; D012119:Respiration
keywords: Air quality; Fetal development; Lung function; Prenatal exposure; Respiratory health