Oxidative potential and water-soluble heavy metals of size-segregated airborne particles in haze and non-haze episodes: Impact of the “Comprehensive Action Plan” in China

The research study discussed in the paper investigated the adsorption/desorption behaviour of heavy metals commonly deposited on urban road surfaces, namely, Zn, Cu, Cr and Pb, for different particle size ranges of solids. The study outcomes, based on field studies and batch experiments, confirmed that road deposited solids particles contain a significantly high amount of vacant charge sites with the potential to adsorb additional heavy metals. Kinetic studies and adsorption experiments indicated that Cr is the most preferred metal element to associate with solids due to the relatively high electronegativity and high charge density of trivalent cation (Cr3+). However, the relatively low availability of Cr in the urban road environment could influence this behaviour. Comparing total adsorbed metals present in solids particles, it was found that Zn has the highest capacity for adsorption to solids. Desorption experiments confirmed that a low concentration of Cu, Cr and Pb in solids was present in water-soluble and exchangeable form, whilst a significant fraction of adsorbed Zn has a high likelihood of being released back into solution. Among heavy metals, Zn is considered to be the most commonly available metal among road surface pollutants.

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The Role of the Humic Substances in the Fractioning of Heavy Metals in Rodrigo de Freitas Lagoon, Rio de Janeiro - Brazil

Anais da Academia Brasileira de Ciências ◽

10.1590/0001-3765201371011 ◽

2013 ◽

Vol 85 (4) ◽

pp. 1289-1301 ◽

Cited By ~ 10

Author(s):

ESTEFAN M. DA FONSECA ◽

JOSE A. BAPTISTA NETO ◽

JOHN MCALISTER ◽

BERNARD SMITH ◽

MARCOS A. FERNANDEZ ◽

...

Keyword(s):

Heavy Metals ◽

Organic Matter ◽

Rio De Janeiro ◽

Water Soluble ◽

Metal Partitioning ◽

Fine Grain ◽

Soluble Phase ◽

The City ◽

South Zone

One of the main results of the processes related to urbanization is the contamination of the adjacent water bodies. Inserted in this context, the Rodrigo de Freitas lagoon is situated in the south zone of the city of Rio de Janeiro. This ecosystem receives several inputs containing all sorts of pollutants, including heavy metals. The present work aimed to study the partitioning of heavy metals in the sediments of Rodrigo de Freitas and the influence of organic matter in this fractionation dynamic. The results of these analyses presented the contents of organic matter as an important metal-capturing agent. Fractionation of organic matter resulted in a predominance of humine. Heavy metal partitioning showed that the metals bound by the water-soluble phase have no significant concentrations. Special features such as, reducing sediment, high levels of organic matter and fine grain size have transformed this ecosystem in an effective deposit of pollutants, where heavy metals are not available in easily reactive fractions.

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Heavy metals removal from wastewaters of phosphoric acid production: a comparison of hybrid liquid membrane (HLM) and aqueous hybrid liquid membrane (AHLM) technologies

Water Science & Technology Water Supply ◽

10.2166/ws.2001.0106 ◽

2001 ◽

Vol 1 (5-6) ◽

pp. 119-129 ◽

Cited By ~ 6

Author(s):

V. Kislik ◽

A. Eyal

Keyword(s):

Heavy Metals ◽

Phosphoric Acid ◽

Cation Exchange ◽

Liquid Membrane ◽

Membrane Resistance ◽

Water Soluble ◽

Separation System ◽

Membrane Systems ◽

Membrane Pore ◽

Cyanex 302

Selective removal of heavy metal ions from industrial wet-process phosphoric acid (WPA) was studied, using the two liquid membrane systems: Hybrid Liquid Membrane (HLM) and Aqueous Hybrid Liquid Membrane (AHLM). Monothiophosphinic acid (Cyanex 302) in kerosene (for the HLM) and Polyvinylsulfonic acid (PVSA) aqueous solution (for the AHLM) were used as a liquid membrane (LM), separated from the feed and strip streams by neutral or cation-exchange membranes. On application of the HLM separation system, the permeation from the feed to the strip phase followed the selectivity sequence: Zn >> Cd > Cu with all types of membranes used. Results show that the selective separation of Cd and Zn from the WPA may be achieved by the HLM with cation-exchange membranes, using a single set-up installation at continuous processing. Copper is accumulated in the Cyanex 302, poisoning the carrier. So, this carrier and HCl as a strip solution can not be recommended for the HLM processing of WPA. Using the AHLM separation system, heavy metals such as cadmium and copper, were successfully recovered from the WPA: average fluxes (in mol/m2sec) to the strip phase were 3.7 × 10-7 and 6.7 × 10-7. Satisfactory dynamic selectivity to copper (≈16) was found. The transfer of iron and zinc species to the strip phase was below detection levels during the 144 hrs of the AHLM experiment. Contamination of the feed and strip solutions by PVSA was not observed during the 500 hrs of processing. The membranes were completely regenerable and used repeatedly. In comparison with the HLM and other liquid membrane systems, the AHLM can potentially provide many operational, economic and environmental advantages, some of them being higher transport rates, low carrier losses and low contamination of the feed and strip solutions by water-soluble polymers, long membrane lifetime, ambient temperature, low energy requirements and chemical consumption, no special requirements for membrane resistance in organic solvents, and fewer limitations on the variability of membrane pore sizes, etc.

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Characterization and comparison of PM<sub>2.5</sub> oxidative potential assessed by two acellular assays

Atmospheric Chemistry and Physics ◽

10.5194/acp-20-5197-2020 ◽

2020 ◽

Vol 20 (9) ◽

pp. 5197-5210 ◽

Cited By ~ 3

Author(s):

Dong Gao ◽

Krystal J. Godri Pollitt ◽

James A. Mulholland ◽

Armistead G. Russell ◽

Rodney J. Weber

Keyword(s):

Metal Ions ◽

Water Soluble ◽

Metal Species ◽

Urban Site ◽

Chemical Components ◽

Linear Regression Models ◽

Oxidative Potential ◽

Metal Interactions ◽

Metal Metal

Abstract. The capability of ambient particles to generate in vivo reactive oxygen species (ROS), called oxidative potential (OP), is a potential metric for evaluating the health effects of particulate matter (PM) and is supported by several recent epidemiological investigations. Studies using various types of OP assays differ in their sensitivities to varying PM chemical components. In this study, we systematically compared two health-relevant acellular OP assays that track the depletion of antioxidants or reductant surrogates: (i) the synthetic respiratory-tract lining fluid (RTLF) assay that tracks the depletion of ascorbic acid (AA) and glutathione (GSH) and (ii) the dithiothreitol (DTT) assay that tracks the depletion of DTT. Yearlong daily samples were collected at an urban site in Atlanta, GA (Jefferson Street), during 2017, and both DTT and RTLF assays were performed to measure the OP of water-soluble PM2.5 components. PM2.5 mass and major chemical components, including metals, ions, and organic and elemental carbon were also analyzed. Correlation analysis found that OP as measured by the DTT and AA depletion (OPDTT and OPAA, respectively) were correlated with both organics and some water-soluble metal species, whereas that from the GSH depletion (OPGSH) was exclusively sensitive to water-soluble Cu. These OP assays were moderately correlated with each other due to the common contribution from metal ions. OPDTT and OPAA were moderately correlated with PM2.5 mass with Pearson's r=0.55 and 0.56, respectively, whereas OPGSH exhibited a lower correlation (r=0.24). There was little seasonal variation in the OP levels for all assays due to the weak seasonality of OP-associated species. Multivariate linear regression models were developed to predict OP measures from the particle composition data. Variability in OPDTT and OPAA were not only attributed to the concentrations of metal ions (mainly Fe and Cu) and organic compounds but also to antagonistic metal–organic and metal–metal interactions. OPGSH was sensitive to the change in water-soluble Cu and brown carbon (BrC), a proxy for ambient humic-like substances.

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Impact of heavy metals on water, fish (Cyprinus carpio) and sediments from a water tank at Tumkur, India

Oceanological and Hydrobiological Studies ◽

10.2478/v10009-009-0017-5 ◽

2009 ◽

Vol 38 (2) ◽

Cited By ~ 4

Author(s):

B. Sreedhara Nayaka ◽

S. Ramakrishna ◽

Jayaprakash ◽

M. Delvi

Keyword(s):

Heavy Metals ◽

Total Concentration ◽

Atomic Absorption Spectrophotometry ◽

Water Soluble ◽

Water Tank ◽

Lead And Cadmium ◽

Nickel Chromium ◽

Soil Sediment ◽

Water Fish ◽

Tank System

Impact of heavy metals on water, fish (This study was carried out to assess the concentrations of various heavy metals and their distribution in a hyper-eutrophic urban Tumkur tank system, which is being polluted from industrial, domestic and sewage effluents. Samples of water, fish and soil sediment were analyzed for the concentration of seven heavy metals (iron, zinc, copper, nickel, chromium, lead and cadmium) using atomic absorption spectrophotometry. The water-soluble (bioavailable) fractions of heavy metals correlated positively with their total concentration, exhibiting the following sequence of bioavailability: Zn > Cd > Ni > Pb > Cu > Cr > Fe.

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Speciation of heavy metals in airborne particles, road dusts, and soils along expressways in China

Chinese Journal of Geochemistry ◽

10.1007/s11631-013-0651-1 ◽

2013 ◽

Vol 32 (4) ◽

pp. 420-429 ◽

Cited By ~ 5

Author(s):

Li Shao ◽

Huayun Xiao ◽

Daishe Wu

Keyword(s):

Heavy Metals ◽

Airborne Particles ◽

Road Dusts

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Study on water-soluble iron, heavy metals and harmful elements of Magnetitum

China Journal of Chinese Materia Medica ◽

10.4268/cjcmm20111205 ◽

2011 ◽

Author(s):

FU Xingsheng

Keyword(s):

Heavy Metals ◽

Water Soluble ◽

Soluble Iron

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Toxicity Assessment of Sediments with Natural Anomalous Concentrations in Heavy Metals by the Use of Bioassay

International Journal of Chemical Engineering ◽

10.1155/2010/101390 ◽

2010 ◽

Vol 2010 ◽

pp. 1-6 ◽

Cited By ~ 9

Author(s):

Francisco Martín ◽

Marlon Escoto ◽

Juan Fernández ◽

Emilia Fernández ◽

Elena Arco ◽

...

Keyword(s):

Heavy Metals ◽

Vibrio Fischeri ◽

Toxicity Assessment ◽

Water Soluble ◽

Ultramafic Rocks ◽

Moderate Degree ◽

Toxicity Bioassay ◽

Potential Toxicity ◽

Riverbed Sediments ◽

Low Degree

The potential toxicity in riverbed sediments was assessed with a bioassay using the bioluminescent bacteriaVibrio fischeri. The selected area was characterized by the presence of ultramafic rocks (peridotites), and the sediments had high values in Ni, Cr, and Co. For the toxicity bioassay withVibrio fischeri, water-soluble forms were used. The results indicated that most of the samples had a very low degree of toxicity, with 10% of reduction in luminescence in relation to the control; meanwhile 25% of the samples had a moderate degree of toxicity with a reduction in luminescence between 13 and 21% in relation to the control. The toxicity index correlated significantly with the concentrations of Ni and Cr in the water extracts. This toxicity bioassay was proved to be a sensitive and useful tool to detect potential toxicity in solutions, even with anomalous concentrations in heavy metals of natural origin.

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