Mechanisms of Mobilization and Attenuation of Inorganic Contaminants in Coal Ash Basins

Sandhu, Shingara S.; Mills, Gary L.

doi:10.1021/bk-1991-0468.ch017

Cited by 4 publications

(4 citation statements)

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“…Presumed CCW contaminated toads were collected from (1) an ash settling basin that is partially filled (∼7 ha) with CCW and has become revegetated and (2) a floodplain wetland approximately 600 m from the ash basin that received CCW effluents from the 1950s through the 1970s. Sediments in this area are comprised almost entirely of CCW that is enriched with trace elements, the primary contaminants of concern in this waste material. , Most organic contaminants are volatilized during the combustion process, and the remaining organic compounds (e.g., PAHs) in CCW tend to not be readily bioavailable. − The reference site was Rainbow Bay, a ∼1-ha Carolina bay wetland, , with no previously known contamination, , located approximately 12 km from the contaminated site. Both locations contain amphibian breeding sites that are surrounded by mixed pine–hardwood forest with some open field habitats.…”

Section: Methodsmentioning

confidence: 99%

Maternal Transfer of Contaminants and Reduced Reproductive Success of Southern Toads (Bufo [Anaxyrus] terrestris) Exposed to Coal Combustion Waste

Metts

Buhlmann

Tuberville

et al. 2013

Environ. Sci. Technol.

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Bioaccumulation of contaminants and subsequent maternal transfer to offspring are important factors that affect the reproductive success of wildlife. However, maternal transfer of contaminants has rarely been investigated in amphibians. We examined maternal transfer of trace elements in southern toads ( Bufo[Anaxyrus] terrestris) residing in two locations: (1) an active coal combustion waste (CCW) disposal basin and adjacent 40-ha floodplain contaminated with CCW over 35 years ago and (2) an uncontaminated reference site. Our study is among the few to document tissue concentration-dependent maternal transfer of contaminants and associated adverse effects in amphibians. We found that females collected from the CCW-contaminated area had elevated concentrations of Ni, Se, and Sr; these females also transferred elevated levels of Cu, Pb, Se, and Sr to their eggs compared to females from the reference site. Overall reproductive success, estimated as a function of clutch size and offspring viability, was reduced by 27% in clutches collected from parents from the contaminated site compared to the reference site. Offspring viability negatively correlated with female and/or egg concentrations of Se and Ni. Reproductive success negatively correlated with Se and Cu concentrations in females, and Se concentrations in eggs. Our study highlights how exposure to CCW can negatively affect amphibian reproduction.

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Section: Methodsmentioning

confidence: 99%

Maternal Transfer of Contaminants and Reduced Reproductive Success of Southern Toads (Bufo [Anaxyrus] terrestris) Exposed to Coal Combustion Waste

Metts

Buhlmann

Tuberville

et al. 2013

Environ. Sci. Technol.

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“…Polyak et al (1994) reported only 2% of total Ni and 13% of the total Cu extracted in this fraction of coal fly ash samples. Sandhu and Mills (1991) found 90% of Ni in ash basin in this fraction and concluded that Ni must have been incorporated into the organic carbon as black coatings on minerals during combustion. Complexation of trace elements by organic ligands plays an important role in their transport in aquatic system, influencing their solubility and uptake by biota.…”

Section: Organic Boundyoxidisable Fractionmentioning

confidence: 98%

Speciation of some heavy metals in coal fly ash

Chaudhary

Banerjee

2007

Chemical Speciation & Bioavailability

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Selected heavy metals Cu, Ni, Zn and Pb were studied in two different types of coal fly ash samples, dyke and field, collected from Badarpur Thermal Power Station, Delhi, India for their total metal concentration as well as geochemical differentiation in different chemical fraction namely exchangeable, easily reducible or Fe -Mn bound, organic or sulfide bound and residual fractions. The total concentration of heavy metals in both types of fly ash samples followed the order Cr4Zn4Pb4Ni4Cu. Among the two types of samples, field fly ash samples were more enriched in these heavy metals compared with the dyke type samples. The fine grain size of field type samples possibly provided the sufficiently large surface area for the adsorption of these metals, resulting in higher concentrations compared with those in the coarse grained dyke samples. But, interestingly, the dyke type fly ash samples contain most of the metals in the exchangeable fraction. Metals in this fraction are easily mobilisable or can be made mobile depending upon the environmental conditions of Eh and pH. This suggests that the dyke type samples with low bulk metal content can even pose serious environmental hazards compared to the high total metal containing samples of field type. This suggests that it is the presence of metal in particular fraction(s) and not the total metal concentrations which are harmful to the environment, in particular to the soil and aquatic life.

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“…[3] Among the three major industrial waste, coal fly ash was selected for its' incomparable abundance, fairly good content of rare earths, no radioactivity issues involved like beach sand sources, and no comminution is required to start the recovery process thereby avoiding the energy intensive step in the first place itself. On the other hand, coal fly ash is environmentally hazardous [4][5][6][7][8][9][10][11] too. So utilization of the wastes coupled with garnering values from them kindles the research and developmental works upon them.…”

Section: Introductionmentioning

confidence: 99%

Combined Experimental and Theoretical Insights on Selectivity of Rare Earth Elements with Tetra‐2‐ethylhexyl Diglycolamide

Mondal,

Singh,

Sharma

et al. 2023

ChemistrySelect

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A diglycolamide based extractant namely tetra‐2‐ethylhexyl diglycolamide [TEHDGA] has been synthesized and characterized for extraction of rare earths from coal fly ash (CFA). The formation rare earth‐TEHDGA complex in the organic phase was determined from slope analysis method. The same structure was further corroborated by the density functional theoretical calculation. Furthermore, DFT approach was adopted to explain the relative stability of rare earth complex with TEHDGA over other matrix elements like Fe, Ca, Al, Mg of CFA by determining their free energy of extraction. The calculated selectivity trend from the free energy of extraction is obtained after consideration of 1 : 3 stoichiometry for Europium – the representative of all rare earth elements. Thus the correct selectivity order was established from a combined experimental and density functional theoretical studies.

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Mechanisms of Mobilization and Attenuation of Inorganic Contaminants in Coal Ash Basins

Cited by 4 publications

References 0 publications

Maternal Transfer of Contaminants and Reduced Reproductive Success of Southern Toads (Bufo [Anaxyrus] terrestris) Exposed to Coal Combustion Waste

Maternal Transfer of Contaminants and Reduced Reproductive Success of Southern Toads (Bufo [Anaxyrus] terrestris) Exposed to Coal Combustion Waste

Speciation of some heavy metals in coal fly ash

Combined Experimental and Theoretical Insights on Selectivity of Rare Earth Elements with Tetra‐2‐ethylhexyl Diglycolamide

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