Proposal of new distribution coefficients (K-d) of potentially toxic elements in soils for improving environmental risk assessment in the State of Sao Paulo, southeastern Brazil

Autor(es)

Soares, Marcio Roberto ^[1] ; de Souza Sarkis, Jorge Eduardo ^[2] ; Ferracciu Alleoni, Luis Reynaldo ^[3]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Agr Sci Ctr, Dept Nat Resources & Environm Protect, Rodovia Anhanguera, Km 174, POB 173, BR-13600970 Araras, SP - Brazil

^[2] Nucl & Energy Res Inst, Lasers & Applicat Ctr, Ave Lineu Prestes 2242, BR-05508000 Sao Paulo, SP - Brazil

^[3] Univ Sao Paulo, Luiz de Queiroz Coll Agr, Dept Soil Sci, Ave Padua Dias 11, BR-12418900 Piracicaba, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Journal of Environmental Management; v. 285, MAY 1 2021.
• Citações Web of Science: 0

Resumo

Soil solid-solution distribution coefficients (K-d) are used in predictive environmental models to assess public health risks. This study was undertaken to determine K-d for potentially toxic elements (PTE) Cd, Co, Cr, Cu, Ni, Pb, and Zn in topsoil samples (0-20 cm) from 30 soils in the State of Sao Paulo, southeastern Brazil. Batch sorption experiments were carried out, and PTE concentrations in the equilibrium solution were determined by High Resolution Inductively Coupled Plasma Mass Spectrometry (HR-ICPMS). Sorption data was fitted to the Freundlich model. The K-d values were either obtained directly from the slope coefficients of C-type isotherms or derived from the slope of the straight line tangent to the non-linear L-type and H-type isotherms. Stepwise multiple regression models were used to estimate the K-d values through the combined effect of a number of soil attributes {[}pH(H2O), effective cation exchange capacity (ECEC) and contents of clay, organic carbon, and Fe (oxy) hydroxides]. The smallest variation in K-d values was recorded for Cu (105-4598 L kg(-1)), Pb (121-7020 L kg(-1)), Ni (6-998 L kg-1), as variation across four orders of magnitude was observed for Cd (7-14,339 L kg(-1)), Co (2-34,473 L kg(-1)), and Cr (1-21,267 L kg(-1)). The K-d values for Zn were between 5 and 123,849 L kg(-1). According to median values of Kd, PTE were sorbed in the following preferential order: Pb > Cu > Cd > Ni > Zn > Cr > Co. The K-d values were best predicted using metal-specific and highly significant (p < 0.001) linear regressions that included pH(H2O), ECEC, and clay contents. The K-d values reported in this study are a novel result that can help minimize erroneous estimates and improve both environmental and public health risk assessments under humid tropical edaphoclimatic conditions. (AU)

• Processo FAPESP: 03/00192-5 - Comportamento de elementos potencialmente toxicos no solo.
• Beneficiário: Luís Reynaldo Ferracciú Alleoni
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 02/00003-5 - Avaliação do coeficiente de distribuição (Kd) de metais pesados e sua relação com propriedades físico-químicas de solos do estado de São Paulo
• Beneficiário: Marcio Roberto Soares
• Modalidade de apoio: Bolsas no Brasil - Doutorado