Full text
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| Author(s): |
Luis Fernando Amato Lourenço
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | São Paulo. |
| Institution: | Universidade de São Paulo (USP). Faculdade de Medicina (FM/SBD) |
| Defense date: | 2018-04-27 |
| Examining board members: |
Thais Mauad;
Claudia Maria Bógus;
Mitiko Saiki
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| Advisor: | Thais Mauad |
| Abstract | |
Urban vegetable gardens have steadily increased worldwide playing a significant role in the strengthening of sustainable urban food systems. Although urban gardens provide multiple benefits to society, the extent to which vegetables are contaminated by the absorption of chemical elements and compounds derived from atmospheric deposition is unclear raising questions about how safe is the cultivation of foods in superlative metropolises. This thesis was designed to evaluate the influence of air pollution on leafy vegetables cultivated in gardens of São Paulo, Brazil. We quantified the concentrations of 17 elements (traffic-related and those essential to plant biology) and 16 polycyclic aromatic hydrocarbons (PAHs) absorbed in the edible tissues of Brassica oleracea var. acephala (collard greens) and Tetragonia tetragonioides (Pall.) Kuntze (spinach). In addition, to verify a correlation between the chemical elements found in collard greens/spinach and those from air pollution particles, we simultaneously exposed specimens of the air plant Tillandsia usneoides L. (Bromeliaceae). Also, we evaluated the use of two biomonitoring methods: the micronuclei frequencies for early tetrads of Tradescantia pallida (Rose) Hunt. cv. \"Purpurea\" Boom (hereafter, Trad-MCN) as a short-term indicator of genotoxic response and tree barks to quantify the accumulation of traffic-related chemical elements as a long-term biomarker of air pollution in urban gardens. Multivariate analysis was used to correlate the elemental concentrations, biomonitoring results and the characteristics of the local urban environment, such as weather variables, traffic burden and vertical obstacles 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 vehicular traffic, vertical obstacles and local weather. 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. The frequency of Trad-MCN had a significant correlation with traffic variables and chemical elements related to road dust and tailpipe emissions deposited in tree barks. Negative associations between Trad-MCN and both the distance through traffic and the presence of vertical obstacles were observed in the vegetable gardens. The Mn and Zn concentration in tree barks were associated with increased Trad-MCN. The levels of PAHs in both vegetables over 45-day periods were < 1 ug kg-1. Air pollution exerts a direct influence in the absorption of urban particles, which may reach levels above the recommended values for consumption (AU) | |
| FAPESP's process: | 14/19201-9 - Determination of trace metals concentrations derived from atmospheric depositions in urban gardens of São Paulo city |
| Grantee: | Luís Fernando Amato Lourenço |
| Support Opportunities: | Scholarships in Brazil - Doctorate (Direct) |