title: The influence of atmospheric particles on the elemental content of vegetables in urban gardens of Sao Paulo, Brazil.
abstract: Although urban horticulture provides multiple benefits to society, the extent to which these vegetables are contaminated by the absorption of chemical elements derived from atmospheric deposition is unclear. This study was designed to evaluate the influence of air pollution on leafy vegetables in community gardens of Sao Paulo, Brazil. Vegetable seedlings of Brassica oleracea var. acephala (collard greens) and Spinacia oleracea (spinach) obtained in a non-polluted rural area and growing in vessels containing standard uncontaminated soil were exposed for three consecutive periods of 30, 60 and 90 days in 10 community gardens in Sao Paulo and in one control site. The concentrations of 17 chemical elements (traffic-related elements and those essential to plant biology) were quantified by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Tillandsia usneoides L. specimens were used as air plant biomonitors. The concentrations of As, Cd, Cr and Pb found in vegetables were compared to the recommended values for consumption. Principal Component Analysis (PCA) was used to cluster the elemental concentrations, and Generalized Linear Models (GLMs) were employed to evaluate the association of the factor scores from each PCA component with variables such as local weather, traffic burden and vertical barriers adjacent to the gardens. We found significant differences in the elemental concentrations of the vegetables in the different community gardens. These differences were related to the overall traffic burden, vertical obstacles and local weather. The Pb and Cd concentrations in both vegetables exceeded the limit values for consumption after 60 days of exposure. A strong correlation was observed between the concentration of traffic-related elements in vegetables and in Tillandsia usneoides L. An exposure response was observed between traffic burden and traffic-derived particles absorbed in the vegetables. Traffic-derived air pollution directly influences the absorption of chemical elements in leafy vegetables, and the levels of these elements may exceed the recommended values for consumption.
authors.affiliation: Department of Pathology, Faculty of Medicine of University of Sao Paulo, Sao Paulo, Sao Paulo, Brazil; National Institute for Integrated Analysis of Environmental Risk (INAIRA), Brazil.
authors.forename: Luís Fernando
authors.initials: LF
authors.lastname: Amato-Lourenco
authors.affiliation: Department of Pathology, Faculty of Medicine of University of Sao Paulo, Sao Paulo, Sao Paulo, Brazil.
authors.forename: Tiana Carla Lopes
authors.initials: TCL
authors.lastname: Moreira
authors.affiliation: Faculty of Pharmaceutical Sciences of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil.
authors.forename: Vanessa Cristina
authors.initials: VC
authors.lastname: de Oliveira Souza
authors.affiliation: Faculty of Pharmaceutical Sciences of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil.
authors.forename: Fernando
authors.initials: F
authors.lastname: Barbosa
authors.affiliation: Nuclear and Energy Research Institute - IPEN-CNEN/SP, Sao Paulo, Sao Paulo, Brazil; National Institute for Integrated Analysis of Environmental Risk (INAIRA), Brazil.
authors.forename: Mitiko
authors.initials: M
authors.lastname: Saiki
authors.affiliation: Department of Pathology, Faculty of Medicine of University of Sao Paulo, Sao Paulo, Sao Paulo, Brazil; National Institute for Integrated Analysis of Environmental Risk (INAIRA), Brazil.
authors.forename: Paulo Hilário Nascimento
authors.initials: PHN
authors.lastname: Saldiva
authors.affiliation: Department of Pathology, Faculty of Medicine of University of Sao Paulo, Sao Paulo, Sao Paulo, Brazil; National Institute for Integrated Analysis of Environmental Risk (INAIRA), Brazil. Electronic address: tmauad@usp.br.
authors.forename: Thais
authors.initials: T
authors.lastname: Mauad
mesh_terms: D001937:Brassica / Q000737:chemistry / Q000378:metabolism; D001938:Brazil; D002947:Cities; D004784:Environmental Monitoring; D004787:Environmental Pollution / Q000032:analysis; D000072506:Gardens; D016014:Linear Models; D013058:Mass Spectrometry; D019216:Metals, Heavy / Q000032:analysis* / Q000378:metabolism; D025341:Principal Component Analysis; D012987:Soil / Q000737:chemistry; D018724:Spinacia oleracea / Q000737:chemistry / Q000378:metabolism; D031232:Tillandsia / Q000737:chemistry* / Q000378:metabolism; D014675:Vegetables / Q000737:chemistry* / Q000378:metabolism
chemical_list: D019216:Metals, Heavy; D012987:Soil
keywords: Food safety; ICP-MS; Risk assessment; Urban gardens; Urban horticulture