Bioavailability of Barium to Plants and Invertebrates in Soils Contaminated by Barite

Abstract

Barium (Ba) is a nonessential element to terrestrial organisms and is known to be toxic at elevated concentrations. In this study, the bioavailability and toxicity of Ba in barite (BaSO4) contaminated soils was studied using standard test organisms (Lactuca sativa L. "Great Lakes", Eisenia fetida). Contamination resulted from barite mining activities. Barium concentrations in contaminated soils determined by X-ray fluorescence were in the range 0.13-29.2%. Barite contaminated soils were shown to negatively impact both E. fetida and L. sativa relative to control soil. For E. fetida, pore-water concentrations and acid extractable Ba were linearly related to % body weight loss. In L. sativa, pore-water Ba and exchangeable Ba were both strongly related to shoot Ba and shoot biomass production. A negative linear relationship was observed between shoot Ba content and shoot weight (P < 0.0004, R(2) = 0.39), indicating that Ba accumulation is likely to have induced phytotoxicity. Plant weights were correlated to % weight loss in earthworm (r = -0.568, P = 0.028). Barium concentrations in pore-water were lower than predicted from barite solubility estimates but strongly related to exchangeable Ba, indicating an influence of ion exchange on Ba solubility and toxicity to E. fetida and L. sativa.

Concentrations of lead, cadmium and barium in urban garden-grown vegetables: The impact of soil variables

“…Recent research has indicated a potential for substantial Ba uptake into leafy crops in particular, with concentrations reaching 100 mg kg−1 (d.w.) or higher (Lamb et al, 2013; Nabulo et al, 2012). One greenhouse study demonstrated Ba uptake into vegetables grown in soils spiked with barium sulfate (Coscione and Berton, 2009).…”

“…Thus, the Ba contents of these urban garden vegetables can be reasonably attributed to plant uptake via roots, with minimal transfer into the fruiting parts of the vegetables. Despite the evidence for physiological uptake, soil total Ba failed to predict crop Ba content, probably because the solubility of Ba in soils is low and dependent on a number of soil properties (Lamb et al, 2013). Our limited survey suggests that similarly high Ba concentrations in leafy green and root vegetables purchased at the market are commonly encountered (Table 2).…”

Lead (Pb) and other metals in New York City community garden soils: Factors influencing contaminant distributions

“…Elemental mapping showed the Pb-rich particles to contain relatively high phosphorus (P) and chlorine (Cl) (results not shown), consistent with the presence of the lead phosphate mineral pyromorphite. In contrast, the Ba-rich particles were invariably associated with high S (Figure 4), suggesting the Ba is likely present in the form of barite (BaSO 4 ), which is highly insoluble and much less toxic than more soluble forms of the element (Lamb et al, 2013). …”

Can liming reduce barium uptake by agricultural plants grown on sandy soil?

“…Suwa et al (2008) observed phytotoxic effects of Ba in soybean plants, expressed as inhibition of photosynthesis. Despite the low solubility of BaSO 4 , uptake of Ba by test organisms from barite‐contaminated soils induced phytotoxicity ( Lamb et al, 2013). However, research on the mechanisms controlling Ba adsorption and uptake by plants from natural soils is scarce.…”