Surface adsorption, intracellular accumulation and compartmentalization of Pb(II) in batch-operated lagoons with Salvinia minima as affected by environmental conditions, EDTA and nutrients

Abstract

The effects of environmental factors and nutrients on the various possible removal mechanisms (surface adsorption, intracellular accumulation and precipitation to sediments) and partitioning of lead among various compartments (plant biomass, water column and sediments) in Salvinia minima batch-operated lagoons, were evaluated. Surface adsorption was found to be the predominant mechanism for Pb(II) removal under all environmental conditions tested in the absence of nutrients (an average of 54.3%) and in a nutrient medium (modified Hutner 1/10 medium) free of EDTA and phosphates (54.41%) at "high" initial Pb(II) concentrations (in the range of 10.3+/-0.13 to 15.2+/-0.05 mg/L). Under these conditions, the bioconcentration factors (BCFs) were 2,431+/-276 and 2,065+/-35, respectively. Lead removal was very rapid during the first 4 h and reached 70% in the absence of nutrients at the "medium" light intensity and temperature (LIT) tested, 88% in nutrient medium free of EDTA and supplemented with synthetic wastewater (at the "lowest" LIT tested), and 85% in medium free of EDTA and phosphates. It was concluded that the mechanisms of lead removal by S. minima, and the compartmentalization of this metal in the microcosm of batch-operated lagoons, are primarily a function of the presence of certain nutrients and chelants, with secondary dependence on environmental conditions. In addition, the results indicate that the percentage of lead removed is only a gross parameter and that the complementary use of BCF and compartmentalization analysis is required to gain a full insight into the metal removal process.

Assessment of the Hyperaccumulating Lead Capacity of Salvinia minima Using Bioadsorption and Intracellular Accumulation Factors

“…To assess the distribution of lead among various compartments of the experimental microcosms (the plant tissue, the water column and the sediments), a compartmentalization analysis was carried out as described by Olguín et al (2005). Biomass was collected and washed with deionized water to remove residues from the medium at the end of each exposure time in the kinetic experiments.…”

“…It has many advantages for use in phytoremediation, including its higher capacity for treating high-strength organic wastewater compared to that of Spirodela polyrrhiza (Olguín et al 2007) and its efficiency for nutrient removal from coffee processing plant wastewaters (Olguín et al 2003). S. minima has also been reported as a hyperaccumulator of Cd 2+ and Pb 2+ (Olguín et al 2005). Surface adsorption and intracellular accumulation were found to be the main mechanisms for lead removal using a free EDTA and phosphate medium in batch systems.…”

“…Surface adsorption and intracellular accumulation were found to be the main mechanisms for lead removal using a free EDTA and phosphate medium in batch systems. The relevance of using a compartmentalization analysis complementary to the use of Bioconcentration Factors (BCF) and metal removal kinetics, to gain full insight into the process of heavy metal removal by plants, has also been demonstrated (Olguín et al 2005).…”

Biological Control of Heavy Metal Pollutants in Water by Salvinia molesta

“…As the concentration of contaminants increased, at high concentrations, Mercury was recorded to have been accumulated more in Salvinia molesta (up to 74%). Dushenkov et al, 1995;Rai et al, 1995;Schneider and Rubio, 1999;Skinner et al, 2007;Olguín et al, 2002;Sune et al, 2007;Sánchez-Galván et al, 2008;Xu et al, 2009;Banerjee and Sarkar, 1997;Hoffman et al, 2004;Espinoza-uinones et al, 2005;Mukherjee and Kumar, 2005;Molisani et al,2006;Sune et al, 2007;Olguin et al, 2005;Heike Bradl, 2005;Sweta kumara et al, (2016) etc.…”

Copper Removal Efficiency in a Surface Water and Compartmentalization in the Floating Fern Salvinia minima

“…Generally, EDTA (Ethylenediaminetetraacetic acid) is one of the more widely used extractants in the analysis of metals compartmentalization in plants. More recently, compartmentalization analysis was applied to macrophytes [6,7], encouraged by the use of emergent or floating aquatic plants for heavy metals removal from wastewaters.…”