Assessment of bioavailability and mobility of major and trace elements in agricultural soils collected in Port St Johns, Eastern Cape, South Africa using single extraction procedures and pseudo-total digestion

Abstract

Purpose The aim of this study was to evaluate the applicability of ultrasound assisted single extraction and pseudo-total digestion procedures to investigate the bioavailability and mobility of major and trace elements collected from agricultural soil collected in Mzimvubu farmstead area located in Port St Johns, Eastern Cape Province (South Africa). Materials and methods The potential metal availability was assessed using complexing agent (ethylenediaminetetraacetic acid (EDTA)), mild (cacium chloride (CaCl 2 ) and ammonium nitrate (NH 4 NO 3 )), deionized water and acidic (CH 3 COOH) extractants with the assistance of ultrasound to evaluate mobility and bioavailability of metals. The ultrasound radiation was used to assist the single extraction of major and trace metals from agricultural soils as well shortening the extraction time. The pseudo-total metal content in agricultural soils was obtained using pseudo-total digestion employing aqua-regia. Results and discussionThe results obtained using different solvents for single extraction procedures, revealed that higher extraction of Al (256-681 mg kg −1 ), Fe (172-430 mg kg −1 ) and Mn (35-136 mg kg −1 ), was observed compared to other metals. Among the investigated solvents, deionized water, acetic acid and EDTA proved to be the most aggressive extractants. The geoaccumulation index (2-6) and contamination factor (3-6) demonstrated that Fe, Cr, Mn, Co, Cu, Ni, and Zn could pose significant environmental contamination risk. Conclusions Based on the results obtained, it can be concluded that the high levels of some studied metals was due to anthropogenic activities.

Evaluation of Element Mobility in River Sediment Using Different Single Extraction Procedures and Assessment of Probabilistic Ecological Risk

“…Calcium chloride extractable About 2 g of the sediment sample was weighed into a 50 mL centrifuge tube, and mL 0.01 M CaCl 2 was added. The solution thus prepared was shaken for 3 h on a rotary shaker (Heidolph) [21][22][23].…”

Comparative assessment of phytoavailable cadmium by using various extractants in texturally different contaminated soils during the growth of maize crop

“…Single extraction technique can be used to provide useful information on bioavailability and toxicity fractions of potentially harmful Cd metal that is present in the soil for plant uptake (Milicevic et al, 2017;Jalali and Hurseresht, 2020). Single extraction technique is cost-effective approach for extracting the trace elements fractionation from soils according to their different mobility and potential bioavailability (Sihlahla et al, 2020). The lack of consistency among the various procedures used, which prevents the standardization of these methods and makes data comparison difficult is the fundamental drawback of single extraction methods (Pueyo et al, 2004;Zhu et al, 2019).…”

“…Sequential extraction methods are time-consuming and laborious methods as compared to single extraction method which uses a single extractant to extract the trace metal (Kumkrong et al, 2022;Mbodji et al, 2022). Several single extraction techniques which are using single extracting solvents such as neutral salts NaNO3, NH4AOc, and CaCl2 are used to evaluate the mobility and availability of Cd metal fractions in soil (Jalali and Hurseresht, 2020;Ma et al, 2020;Sihlahla et al, 2020).…”

Physiological Responses and Adaptations of the Halophyte Atriplex halimus to Soil Contaminated with Cd, Ni, and NaCl

“…Their persistent nature is a severe threat to the environment, and affects the lives of plants, animals, and humans. Once they enter the body, they accumulate in vital organs for years causing severe health problems [1]. Effects of PTE poisoning can be toxic, carcinogenic, mutagenic, or teratogenic [2].…”