title: Source and pathway analysis of lead and polycyclic aromatic hydrocarbons in Lisbon urban soils.
abstract: One hundred soil samples were collected from urban spaces, in Lisbon, Portugal, in two surveys that were carried out in consecutive years, to assess the potential adverse human health effects following exposure to potentially toxic elements and organic compounds in the urban soils. The study hereby described follows on from the earlier work of the authors and aims at performing a source-pathway-fate analysis of lead (Pb) and polycyclic aromatic hydrocarbons (PAHs) in the urban soils in order to increase current knowledge on factors influencing exposure of the population. Various techniques were combined to achieve the proposed goal. Geogenic and anthropogenic sources were apportioned by means of Pb isotope mixing models. Isotope data was further coupled with geographic information system mapping to assess local mixed sources of Pb and PAHs. Unleaded vehicle exhaust and cement production show the largest relative contribution to the total soil-Pb, but their respective importance depends on factors such as location and urban landscape. The primary sources of PAHs to the urban soils are probably air and land traffic. Multivariate analysis was used to investigate which soil properties could influence mobility and fate of the contaminants. Whilst principal components analysis indicates carbonates and other calcium phases as probable factors controlling the dispersion of Pb in the urban soils, the linear models obtained from stepwise multiple regression analysis show that soil phosphorous (P) and manganese (Mn) are good predictors of the total soil Pb content. No robust model was obtained for the PAHs, impeding identifying environmental factors most likely to influence their dispersion in the urban soils. The solid-phase distribution study provided critical information to untangle the, at a first glance, contradictory results obtained by the multivariate analysis. Carbonates and other calcium phases, having these a probable anthropogenic origin, are soil components containing major fractions of Pb, P, and Mn.
authors: GEOBIOTEC, Departmento de Geociências, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal. Electronic address: pmarinho@ua.pt.
authors: Amélia Paula
authors: AP
authors: Marinho Reis
authors: Department of Earth Sciences, Durham University, CESAM, Durham DH1 3LE, United Kingdom.
authors: Thomas
authors: T
authors: Shepherd
authors: Department of Earth Sciences, Durham University, CESAM, Durham DH1 3LE, United Kingdom; CERENA, Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
authors: Geoff
authors: G
authors: Nowell
authors: Departmento de Química, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors: Anabela
authors: A
authors: Cachada
authors: Departmento de Química, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors: Armando Costa
authors: AC
authors: Duarte
authors: British Geological Survey, Keyworth, Nottingham NG12 5GG, United Kingdom.
authors: Mark
authors: M
authors: Cave
authors: British Geological Survey, Keyworth, Nottingham NG12 5GG, United Kingdom.
authors: Joanna
authors: J
authors: Wragg
authors: GEOBIOTEC, Departmento de Geociências, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors: Carla
authors: C
authors: Patinha
authors: GEOBIOTEC, Departmento de Geociências, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors: Ana
authors: A
authors: Dias
authors: GEOBIOTEC, Departmento de Geociências, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors: Fernando
authors: F
authors: Rocha
authors: GEOBIOTEC, Departmento de Geociências, Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro, Portugal.
authors: Eduardo Ferreira
authors: EF
authors: da Silva
authors: LNEG, Estrada da Portela, Zambujal, 2720-866 Amadora, Portugal.
authors: António Jorge
authors: AJ
authors: Sousa
authors: LNEG, Estrada da Portela, Zambujal, 2720-866 Amadora, Portugal.
authors: Cátia
authors: C
authors: Prazeres
authors: LNEG, Estrada da Portela, Zambujal, 2720-866 Amadora, Portugal.
authors: Maria João
authors: MJ
authors: Batista
mesh_terms: D004784:Environmental Monitoring / Q000379:methods*; D007854:Lead / Q000032:analysis*; D015999:Multivariate Analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D011174:Portugal; D012987:Soil / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*; D014507:Urbanization; D001335:Vehicle Emissions / Q000032:analysis*
chemical_list: D011084:Polycyclic Aromatic Hydrocarbons; D012987:Soil; D012989:Soil Pollutants; D001335:Vehicle Emissions; D007854:Lead
keywords: Geographical information system; Lead isotope ratios; Solid-phase fractionation study; Source apportionment; Spatial modelling; Statistical techniques