Advanced search
Start date
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Evaluation of chemical extractants to assess metals phytoavailability in Brazilian municipal solid waste composts

Full text
Asensio, Veronica [1, 2] ; Abreu-Junior, Cassio H. [1] ; da Silva, Fabio Cesar [3] ; Chitolina, Jose Carlos [4]
Total Authors: 4
[1] Univ Sao Paulo, Ctr Energia Nucl Agr, BR-13400970 Piracicaba, SP - Brazil
[2] Univ Sao Paulo, ESALQ, Dept Soil Sci, Av Padua Dias 11, BR-13418900 Piracicaba, SP - Brazil
[3] Embrapa Informat Agr, Empresa Brasileira Pesquisa Agr EMBRAPA, BR-13083886 Campinas, SP - Brazil
[4] Fundacao Municipal Ensino Piracicaba FUMEP, Escola Engn Piracicaba, BR-13414040 Piracicaba, SP - Brazil
Total Affiliations: 4
Document type: Journal article
Source: Environmental Pollution; v. 243, n. B, p. 1235-1241, DEC 2018.
Web of Science Citations: 0

Municipal solid wastes (MSW) can be composted to become an organic fertilizer. However, besides plant nutrients, it can also contain high concentration of some toxic metals than can pollute agricultural soils, contaminate food, animals and human being. A greenhouse experiment was carried out for two purposes: i) to evaluate the concentrations of cadmium, copper, chromium, nickel, lead and zinc in four Brazilian MSW composts, and, ii) to know which is the best solution for extracting those metals in phytoavailable form from the composts. In order to evaluate the phytoavailability of metals, they were extracted with six chemical extractants: i) water, ii) 0.05 mol L-1 Ca(NO3)(2). iii) 0.1 mol L-1 HCl, iv) 0.005 mol L-1 DTPA at pH 7.3, v) 0.05 mol L-1 CaCl2 and vi) Mehlich 3 solution. In addition, lettuces were cultivated as a test plant in pots containing 1.8 kg of MSW compost as substrate. Fifty-six days later, lettuce plants were harvested. New lettuces were then planted for a second cycle, and then harvested after fifty-six days. Semi-total concentration of metals in composts and total in plants was also determined through an extraction with nitric-perchloric acid. Semi total concentration of Cd and Pb exceeded the intervention limits from Brazil in the four studied composts, and lettuce plants were polluted by those two elements. Therefore, compost made of MSW must be characterized before being used for agricultural soils. Copper and nickel in phytoavailable were effectively extracted with the strongest chelating agents used, HCl and Mehlich 3, probably because most metal is bound to organic matter in the compost. Cadmium, chromium, lead and zinc were no efficiently extracted with any of the tested extractants. (C) 2018 Elsevier Ltd. All rights reserved. (AU)