Background concentrations and quality reference values for some potentially toxic elements in soils of São Paulo State, Brazil

Abstract

Quality reference values (QRV) for potentially toxic elements (PTE) in soils are established as a tool for prevention and monitoring of soil pollution. These values should be periodically revised in order to ensure soil safety for agricultural purposes. Brazil is market leader for several commodities; therefore, the safety of Brazilian soils is of worldwide strategic importance. The objective of this study was to determine the natural background concentrations and the QRV for As, Ba, Cd, Cr, Ni, Pb, Se, and Zn by investigating 30 representative pedotypes in the São Paulo State, one of the most important agro-industry economy at worldwide level. Multivariate statistical analysis was applied to determine the sources of PTE and their variability. The mean natural background concentrations of PTE in the soils were generally lower to those reported in literature. QRV, calculated for each element as the 75th and 90th percentiles, were lower (75th for As, Cd, Pb, and Zn), similar (75th for Ba, Cr, and Se) or above (90th for Ba, Cr, and Se and 75-90th for Ni) those previously proposed by the Brazilian environmental protection agencies. The results indicate that 75th percentile may be too restrictive. The PTE in the investigated soils appear to have comes mainly from two primary natural sources: a prevalent one of geogenic and a secondary of pedogenic origin. These results confirm the predominant natural source of selected PTE in the investigated soils, thus sustaining the possibility of using the data set to develop QRV for the State of São Paulo.

Adsorption of lead (Pb) in strongly weathered tropical soil (Ribeira Valley region - Brazil)

“…These concentrations are similar to results available in the literature (Wedepohl 1995) for soils collected in uncontaminated areas (0.10 mg/kg Cd; 17 mg/kg Pb, 52 mg/kg Zn). The results are also comparable to the background concentrations of PTE found by Nogueira et al (2018) for natural soils from São Paulo state, Brazil (0.1 mg/ kg Cd; 10.1 mg/kg Pb, 21.8 mg/kg Zn). Table 3 and Fig.…”

Total and bioaccessible heavy metals in cabbage from major producing cities in Southwest China: health risk assessment and cytotoxicity

“…34 Based on Chen et al, 35 the mean concentrations of As, Cd, Pb and Cr in soils in Yunnan are 19.2, 0.22, 57.6, and 106 mg kg À1 (Table 2), which are 1.2-14 times higher than other regions (except for Cd). [36][37][38][39] In fact, they are higher than the Chinese soil guidelines for Grade I, which are 15, 0.2, 35, and 90 mg kg À1 (Table 2). So, the high metal concentrations in cabbage may contribute to the high metal concentrations in the soils.…”

Distribution of rare earth elements in soils of contrasting geological and pedological settings to support human health assessment and environmental policies

“…420/2009). The 75th percentile is adopted in most studies of QRVs and prioritized by governmental and environmental institutions in Brazil, since it meets its standardization more rigidly and avoids the insertion of anomalous values (Nogueira et al 2018;Santos & Alleoni, 2013). Geostatistical modeling was used to evaluate the spatial distribution of the REE contents.…”