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Dr. Waleed Shetaya
Air Pollution Research Department, Environmental Research Division, National Research Centre, 33 El-Bohouth St., Dokki, Giza 12622, Egypt

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0 Air Pollution
0 Atmospheric Chemistry
0 Biogeochemistry
0 Isotope Geochemistry
0 Waste Management

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Air Pollution
soil pollution

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Review
Published: 07 April 2020 in Environmental Pollution
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Despite the mercury (Hg) control measures adopted by the international community, Hg still poses a significant risk to ecosystem and human health. This is primarily due to the ability of atmospheric Hg to travel intercontinentally and contaminating terrestrial and aquatic environments far from its natural and anthropogenic point sources. The issue of Hg pollution is further complicated by its unique physicochemical characteristics, most noticeably its multiple chemical forms that vary in their toxicity and environmental mobility. This meant that most of the risk evaluation protocols developed for other metal(loid)s are not suitable for Hg. Soil is a major reservoir of Hg and a key player in its global cycle. To fully assess the risks of soil Hg it is essential to estimate its bioavailability and/or availability which are closely linked to its toxicity. However, the accurate determination of the (bio)-available pools of Hg in soils is problematic, because the terms ‘bioavailable’ and ‘available’ are ill-defined. In particular, the term ‘bioavailable pool’, representing the fraction of Hg that is accessible to living organisms, has been consistently misused by interchanging with other intrinsically different terms e.g. mobile, labile, reactive and soluble pools. A wide array of physical, chemical, biological and isotopic exchange methods were developed to estimate the (bio)-available pools of Hg in soil in an attempt to offer a plausible assessment of its risks. Unfortunately, many of these methods do not mirror the (bio)-available pools of soil Hg and suffer from technical drawbacks. In this review, we discuss advantages and disadvantages of methods that are currently applied to quantify the (bio)-availability of Hg in soils. We recommended the most feasible methods and give suggestions how to improve the determination of (bio)-available Hg in soils.

ACS Style

Jen-How Huang; Waleed Shetaya; Stefan Osterwalder. Determination of (Bio)-available mercury in soils: A review. Environmental Pollution 2020, 263, 114323 .

AMA Style

Jen-How Huang, Waleed Shetaya, Stefan Osterwalder. Determination of (Bio)-available mercury in soils: A review. Environmental Pollution. 2020; 263 ():114323.

Chicago/Turabian Style

Jen-How Huang; Waleed Shetaya; Stefan Osterwalder. 2020. "Determination of (Bio)-available mercury in soils: A review." Environmental Pollution 263, no. : 114323.

Journal article
Published: 26 February 2020 in CHIMIA International Journal for Chemistry
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ACS Style

Waleed Shetaya; Jen-How Huang. Reactivity of Soil Mercury by Stable Isotope Dilution. CHIMIA International Journal for Chemistry 2020, 74, 58 -58.

AMA Style

Waleed Shetaya, Jen-How Huang. Reactivity of Soil Mercury by Stable Isotope Dilution. CHIMIA International Journal for Chemistry. 2020; 74 (1):58-58.

Chicago/Turabian Style

Waleed Shetaya; Jen-How Huang. 2020. "Reactivity of Soil Mercury by Stable Isotope Dilution." CHIMIA International Journal for Chemistry 74, no. 1: 58-58.

Journal article
Published: 09 October 2019 in International Journal of Molecular Sciences
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Greater Cairo (Egypt) is a megalopolis where the studies of the air pollution events are of extremely high relevance, for the geographical-climatological aspects, the anthropogenic emissions and the health impact. While preliminary studies on the particulate matter (PM) chemical composition in Greater Cairo have been performed, no data are yet available on the PM's toxicity. In this work, the in vitro toxicity of the fine PM (PM2.5) sampled in an urban area of Greater Cairo during 2017-2018 was studied. The PM2.5 samples collected during spring, summer, autumn and winter were preliminary characterized to determine the concentrations of ionic species, elements and organic PM (Polycyclic Aromatic Hydrocarbons, PAHs). After particle extraction from filters, the cytotoxic and pro-inflammatory effects were evaluated in human lung A549 cells. The results showed that particles collected during the colder seasons mainly induced the xenobiotic metabolizing system and the consequent antioxidant and pro-inflammatory cytokine release responses. Biological events positively correlated to PAHs and metals representative of a combustion-derived pollution. PM2.5 from the warmer seasons displayed a direct effect on cell cycle progression, suggesting possible genotoxic effects. In conclusion, a correlation between the biological effects and PM2.5 physico-chemical properties in the area of study might be useful for planning future strategies aiming to improve air quality and lower health hazards.

ACS Style

Sara Marchetti; Salwa K. Hassan; Waleed H. Shetaya; Asmaa El-Mekawy; Atef Mohamed; Atef M. F. Mohammed; Ahmed A. El-Abssawy; Rossella Bengalli; Anita Colombo; Maurizio Gualtieri; Paride Mantecca. Seasonal Variation in the Biological Effects of PM2.5 from Greater Cairo. International Journal of Molecular Sciences 2019, 20, 4970 .

AMA Style

Sara Marchetti, Salwa K. Hassan, Waleed H. Shetaya, Asmaa El-Mekawy, Atef Mohamed, Atef M. F. Mohammed, Ahmed A. El-Abssawy, Rossella Bengalli, Anita Colombo, Maurizio Gualtieri, Paride Mantecca. Seasonal Variation in the Biological Effects of PM2.5 from Greater Cairo. International Journal of Molecular Sciences. 2019; 20 (20):4970.

Chicago/Turabian Style

Sara Marchetti; Salwa K. Hassan; Waleed H. Shetaya; Asmaa El-Mekawy; Atef Mohamed; Atef M. F. Mohammed; Ahmed A. El-Abssawy; Rossella Bengalli; Anita Colombo; Maurizio Gualtieri; Paride Mantecca. 2019. "Seasonal Variation in the Biological Effects of PM2.5 from Greater Cairo." International Journal of Molecular Sciences 20, no. 20: 4970.

Journal article
Published: 26 April 2019 in Applied Geochemistry
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Chemical fractionation via sequential extraction (SEP) combined with isotopic analysis of Pb was used to investigate the origins and reactivity of Pb in 66 topsoil samples collected from 12 different locations in Egypt. The total soil Pb concentrations (TPb) covered a wide range (∼80–16,000 mg kg−1), but were only elevated in four industrial and urban locations within Cairo and Alexandria. In all the other locations values of TPb were generally low and were close to the average crustal Pb concentration of 14 mg kg−1. The largest Pb fraction in all soils, with the exception of two industrial locations, was the ‘residual’ fraction (38–63% of TPb) followed by Pb bound to ‘organic’ and ‘metal oxide’ phases. The Pb isotopic signatures (206Pb/207Pb vs 208Pb/207Pb) of all samples in all SEP fractions were highly variable, suggesting a heterogeneous mix of Pb contamination sources; however, they aligned closely to a binary mixing line between geogenic and petrol Pb sources. There were similar patterns across all of the non-residual fractions with measureable data (F2 – F4) suggesting that the non-residual anthropogenic-Pb and geogenic-Pb have been assimilated into common pools within the soil. Binary and ternary source-apportionment models based on Pb isotopic ratios and abundances showed that the relative contribution of petrol-Pb and geogenic-Pb can be ascribed with reasonable certainty. However, the contribution of further sources can only be accounted for if the isotopic abundance of all end-members are known and are at the periphery of the soils dataset.

ACS Style

Waleed H. Shetaya; Ezzat R. Marzouk; Elham F. Mohamed; Elizabeth H. Bailey; Scott D. Young. Chemical and isotopic fractionation of lead in the surface soils of Egypt. Applied Geochemistry 2019, 106, 7 -16.

AMA Style

Waleed H. Shetaya, Ezzat R. Marzouk, Elham F. Mohamed, Elizabeth H. Bailey, Scott D. Young. Chemical and isotopic fractionation of lead in the surface soils of Egypt. Applied Geochemistry. 2019; 106 ():7-16.

Chicago/Turabian Style

Waleed H. Shetaya; Ezzat R. Marzouk; Elham F. Mohamed; Elizabeth H. Bailey; Scott D. Young. 2019. "Chemical and isotopic fractionation of lead in the surface soils of Egypt." Applied Geochemistry 106, no. : 7-16.

Journal article
Published: 01 April 2019 in Chemosphere
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Understanding the sorption kinetics of Hg is the key to predicting its reactivity in soils which is indispensable for environmental risk assessment. The temporal change in the solubility of Hg spikes (6 mg kg) added to a range of soils with different properties was investigated and modelled. The sorption of Hg displayed a biphasic pattern with a rapid initial (short-term) phase followed by a slower (time-dependent) one. The overall reaction rate constants ranged from 0.003 to 4.9 h and were significantly correlated (r = 0.94) to soil organic carbon (SOC). Elovich and Spherical Diffusion expressions compellingly fitted the observed Hg sorption kinetics highlighting their flexibility to describe reactions occurring over multiple phases and wide timeframes. A parameterized Elovich model from soil variables indicated that the short-term sorption is solely controlled by SOC while the time-dependent sorption appeared independent of SOC and decreased at higher pH values and Al(OH) and MnO concentrations. This is consistent with a rapid chemical reaction of Hg with soil organic matter (SOM) which is followed by a noticeably slower phase likely occurring through physical pathways e.g. pore diffusion of Hg into spherical soil aggregates and progressive incorporation of soluble organic-Hg into solid phase. The model lines predicted that in soils with >4% SOC, Hg is removed from soil solution over seconds to minutes; however, in soils with <2% SOC and higher pH values, Hg may remain soluble for months and beyond with a considerable associated risk of re-emission or migration to the surrounding environments.

ACS Style

Waleed H. Shetaya; Jen-How Huang; Stefan Osterwalder; Adrien Mestrot; Moritz Bigalke; Christine Alewell. Sorption kinetics of isotopically labelled divalent mercury (196Hg2+) in soil. Chemosphere 2019, 221, 193 -202.

AMA Style

Waleed H. Shetaya, Jen-How Huang, Stefan Osterwalder, Adrien Mestrot, Moritz Bigalke, Christine Alewell. Sorption kinetics of isotopically labelled divalent mercury (196Hg2+) in soil. Chemosphere. 2019; 221 ():193-202.

Chicago/Turabian Style

Waleed H. Shetaya; Jen-How Huang; Stefan Osterwalder; Adrien Mestrot; Moritz Bigalke; Christine Alewell. 2019. "Sorption kinetics of isotopically labelled divalent mercury (196Hg2+) in soil." Chemosphere 221, no. : 193-202.

Journal article
Published: 24 March 2019 in Environmental Pollution
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The Minamata Convention entered into force in 2017 with the aim to phase-out the use of mercury (Hg) in manufacturing processes such as the chlor-alkali or vinyl chloride monomer production. However, past industrial use of Hg had already resulted in extensive soil pollution, which poses a potential environmental threat. We investigated the emission of gaseous elemental mercury (Hg0) from Hg polluted soils in settlement areas in the Canton of Valais, Switzerland, and its impact on local air Hg concentrations. Most soil Hg was found as soil matrix-bound divalent Hg (HgII). Elemental mercury (Hg0) was undetectable in soils, yet we observed substantial Hg0 emission (20–1392 ng m−2 h−1) from 27 soil plots contaminated with Hg (0.2–390 mg Hg kg−1). The emissions of Hg0 were calculated for 1274 parcels covering an area of 8.6 km2 of which 12% exceeded the Swiss soil remediation threshold of 2 mg Hg kg−1. The annual Hg0 emission from this area was approximately 6 kg a−1, which is almost 1% of the total atmospheric Hg emissions in Switzerland based on emission inventory estimates. Our results show a higher abundance of Hg resistance genes (merA) in soil microbial communities with increasing soil Hg concentrations, indicating that biotic reduction of HgII is likely an important pathway to form volatile Hg0 in these soils. The total soil Hg pool in the top 20 cm of the investigated area was 4288 kg; hence, if not remediated, these contaminated soils remain a long-term source of atmospheric Hg, which is prone to long-range atmospheric transport.

ACS Style

Stefan Osterwalder; Jen-How Huang; Waleed Shetaya; Yannick Agnan; Aline Frossard; Beat Frey; Christine Alewell; Ruben Kretzschmar; Harald Biester; Daniel Obrist. Mercury emission from industrially contaminated soils in relation to chemical, microbial, and meteorological factors. Environmental Pollution 2019, 250, 944 -952.

AMA Style

Stefan Osterwalder, Jen-How Huang, Waleed Shetaya, Yannick Agnan, Aline Frossard, Beat Frey, Christine Alewell, Ruben Kretzschmar, Harald Biester, Daniel Obrist. Mercury emission from industrially contaminated soils in relation to chemical, microbial, and meteorological factors. Environmental Pollution. 2019; 250 ():944-952.

Chicago/Turabian Style

Stefan Osterwalder; Jen-How Huang; Waleed Shetaya; Yannick Agnan; Aline Frossard; Beat Frey; Christine Alewell; Ruben Kretzschmar; Harald Biester; Daniel Obrist. 2019. "Mercury emission from industrially contaminated soils in relation to chemical, microbial, and meteorological factors." Environmental Pollution 250, no. : 944-952.

Journal article
Published: 01 March 2018 in Science of The Total Environment
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The current availability of Pb in Egyptian soils and associated plants were studied in 15 locations (n=159) that had been historically subjected to industrial and automobile Pb emissions. Isotopic dilution with enriched (204)Pb was used to estimate the soil Pb labile pool (PbE); results showed that %PbE values were mostly <25% which is likely due to the alkaline nature of the soils. Nonetheless, lability of Pb was significantly higher in urban and industrial locations indicating greater reactivity of anthropogenic Pb in comparison to geogenic-Pb. A plot of (206)Pb/(207)Pb vs (208)Pb/(207)Pb showed that all soils were aligned close to a virtual binary line between two apparent end member signatures (petrol and geogenic-Pb) suggesting that they are the major sources of Pb in the Egyptian environment. Soils with greater Pb concentrations (urban and industrial locations) displayed a significantly greater ratio of labile petrol-Pb to labile geogenic-Pb in comparison to less-contaminated soils. However, this difference was marginal (±5%) suggesting that historically emitted petrol-Pb has substantially mixed with geogenic-Pb into a common pool as a result of prolonged contact with soil. The proportion of petrol-Pb in fruits and leaf vegetables was significantly (P<0.005) greater than that of the associated soils suggesting preferential uptake of the more labile petrol-Pb as opposed to the relatively immobile geogenic-Pb. However, it is also possible that the major source of Pb intake by Egyptian consumers is extraneous Pb dust enriched with petrol Pb rather than systematic Pb via roots uptake.

ACS Style

W.H. Shetaya; Ezzat Marzouk; E.F. Mohamed; M. Elkassas; Elizabeth Bailey; S.D. Young. Lead in Egyptian soils: Origin, reactivity and bioavailability measured by stable isotope dilution. Science of The Total Environment 2018, 618, 460 -468.

AMA Style

W.H. Shetaya, Ezzat Marzouk, E.F. Mohamed, M. Elkassas, Elizabeth Bailey, S.D. Young. Lead in Egyptian soils: Origin, reactivity and bioavailability measured by stable isotope dilution. Science of The Total Environment. 2018; 618 ():460-468.

Chicago/Turabian Style

W.H. Shetaya; Ezzat Marzouk; E.F. Mohamed; M. Elkassas; Elizabeth Bailey; S.D. Young. 2018. "Lead in Egyptian soils: Origin, reactivity and bioavailability measured by stable isotope dilution." Science of The Total Environment 618, no. : 460-468.

Rapid communication
Published: 04 December 2017 in Environmental Science & Technology Letters
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The accurate estimation of soil mercury lability is crucial for risk assessment. In comparison to chemical fractionation and speciation, isotopic dilution (ID) offers precise definition of labile mercury fractions while maintaining the natural equilibrium. We developed and applied an ID protocol with 199Hg to estimate the soil mercury (Hg) isotopically exchangeable (labile) pool or HgE using a range of industrially contaminated soils in Switzerland. The measured HgE values were consistent for the same soil against different spike levels (50, 100, and 200% of native 199Hg), indicating that the spiked and soil isotopes achieved required dynamic equilibrium at the soil–water interface. Total soil Hg (THg; mg kg–1) was the best predictor of HgE (mg kg–1) and %HgE and accounted for 96 and 63% of the variance, respectively. Nonetheless, despite the wide range of THg values (0.37–310 mg kg–1) in the studied soils, Hg lability spanned a narrow range (∼12–25% of THg), highlighting the large capacity of soils to sequester Hg in a very stable form. The “exchangeable pool” of Hg extracted by CH3COONH4 and MgCl2 (<0.25 and <0.32% of THg, respectively) largely underestimated Hg lability in comparison to ID, suggesting the potential usefulness of the ID approach.

ACS Style

Waleed H. Shetaya; Stefan Osterwalder; Moritz Bigalke; Adrien Mestrot; Jen-How Huang; Christine Alewell. An Isotopic Dilution Approach for Quantifying Mercury Lability in Soils. Environmental Science & Technology Letters 2017, 4, 556 -561.

AMA Style

Waleed H. Shetaya, Stefan Osterwalder, Moritz Bigalke, Adrien Mestrot, Jen-How Huang, Christine Alewell. An Isotopic Dilution Approach for Quantifying Mercury Lability in Soils. Environmental Science & Technology Letters. 2017; 4 (12):556-561.

Chicago/Turabian Style

Waleed H. Shetaya; Stefan Osterwalder; Moritz Bigalke; Adrien Mestrot; Jen-How Huang; Christine Alewell. 2017. "An Isotopic Dilution Approach for Quantifying Mercury Lability in Soils." Environmental Science & Technology Letters 4, no. 12: 556-561.

Journal article
Published: 06 April 2017 in Journal of Applied Biotechnology
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A batch process was used to evaluate the potential of regeneration of spent activated carbon (AC) by solvent extraction technique with synergetic to ultra-sonication. Experiments were undertaken as a function of the initial concentration of toluene. Freundlich and Langmuir models were used to study the adsorption isotherms and the data well fitted the Langmuir expression. The maximum adsorption capacities of toluene were found to be 0.108 µg/g activated carbon for Type-I Langmuir. Extraction of the used AC by both methanol solvent and ultrasonic radiation yielded up to 95% reactivation of the spent AC in the first run. Nearly up to 88 % recovery of activity could be achieved after further regeneration and reusing of the spent AC. The results indicate that the coupling of solvent extraction with ultrasonic waves in the AC treatment is comparable and perhaps superior to the conventional regeneration techniques in many cases. This is mainly due to the single step process applied which is less energy consuming; in addition to the nearly comprehensive recovery of the adsorptive capacity of spent AC.

ACS Style

Elham F. Mohamed; Waleed H. Shetaya; Asmaa El-Mekawy; Alia A. Shakour; Gamal Awad. Coupling of Solvent Extraction and Ultrasonic Waves for Regeneration of Spent Activated Carbon after Treatment of Polluted Air with Toluene Vapor. Journal of Applied Biotechnology 2017, 5, 1 .

AMA Style

Elham F. Mohamed, Waleed H. Shetaya, Asmaa El-Mekawy, Alia A. Shakour, Gamal Awad. Coupling of Solvent Extraction and Ultrasonic Waves for Regeneration of Spent Activated Carbon after Treatment of Polluted Air with Toluene Vapor. Journal of Applied Biotechnology. 2017; 5 (2):1.

Chicago/Turabian Style

Elham F. Mohamed; Waleed H. Shetaya; Asmaa El-Mekawy; Alia A. Shakour; Gamal Awad. 2017. "Coupling of Solvent Extraction and Ultrasonic Waves for Regeneration of Spent Activated Carbon after Treatment of Polluted Air with Toluene Vapor." Journal of Applied Biotechnology 5, no. 2: 1.

Technical papers
Published: 25 November 2015 in Journal of the Air & Waste Management Association
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Agricultural wastes such as rice straw, sugar beet, and sugarcane bagasse have become a critical environmental issue due to growing agriculture demand. This study aimed to investigate the valorization possibility of sugarcane bagasse waste for activated carbon preparation. It also aimed to fully characterize the prepared activated carbon (BET surface area) via scanning electron microscope (SEM) and in terms of surface functional groups to give a basic understanding of its structure and to study the adsorption capacity of the sugarcane bagasse-based activated carbon using aqueous methylene blue (MB). The second main objective was to evaluate the performance of sugarcane bagasse-based activated carbon for indoor volatile organic compounds removal using the formaldehyde gas (HCHO) as reference model in two potted plants chambers. The first chamber was labeled the polluted chamber (containing formaldehyde gas without activated carbon) and the second was taken as the treated chamber (containing formaldehyde gas with activated carbon). The results indicated that the sugarcane bagasse-based activated carbon has a moderate BET surface area (557 m2/g) with total mesoporous volume and microporous volume of 0.310 and 0.273 cm3/g, respectively. The prepared activated carbon had remarkable adsorption capacity for MB. Formaldehyde removal rate was then found to be more than 67% in the treated chamber with the sugarcane bagasse-based activated carbon. The plants’ responses for this application as dry weight, chlorophyll contents, and protein concentration were also investigated. Implications: Preparation of activated carbon from sugarcane bagasse (SCBAC) is a promising approach to produce cheap and efficient adsorbent for gas pollutants removal. It may be also a solution for the agricultural wastes problems in big cities, particularly in Egypt. MB adsorption tests suggest that the SCBAC have high adsorption capacity. Formaldehyde gas removal in the plant chambers indicates that the SCBAC have potential to recover volatile gases. The results confirmed that the activated carbon produced from sugarcane bagasse waste raw materials can be used as an applicable adsorbent for treating a variety of gas pollutants from the indoor environment.

ACS Style

Elham F. Mohamed; Mohammed A. El-Hashemy; Nasser Abdel-Latif; Waleed Shetaya. Production of sugarcane bagasse-based activated carbon for formaldehyde gas removal from potted plants exposure chamber. Journal of the Air & Waste Management Association 2015, 65, 1413 -1420.

AMA Style

Elham F. Mohamed, Mohammed A. El-Hashemy, Nasser Abdel-Latif, Waleed Shetaya. Production of sugarcane bagasse-based activated carbon for formaldehyde gas removal from potted plants exposure chamber. Journal of the Air & Waste Management Association. 2015; 65 (12):1413-1420.

Chicago/Turabian Style

Elham F. Mohamed; Mohammed A. El-Hashemy; Nasser Abdel-Latif; Waleed Shetaya. 2015. "Production of sugarcane bagasse-based activated carbon for formaldehyde gas removal from potted plants exposure chamber." Journal of the Air & Waste Management Association 65, no. 12: 1413-1420.

Journal article
Published: 28 October 2011 in Geochimica et Cosmochimica Acta
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We investigated changes in iodine (129I) solubility and speciation in nine soils with contrasting properties (pH, Fe/Mn oxides, organic carbon and iodine contents), incubated for nine months at 10 and 20 °C. The rate of 129I sorption was greater in soils with large organic carbon contents (%SOC), low pH and at higher temperatures. Loss of iodide (I−) from solution was extremely rapid, apparently reaching completion over minutes–hours; iodate (IO3-) loss from solution was slower, typically occurring over hours–days. In all soils an apparently instantaneous sorption reaction was followed by a slower sorption process for IO3-. For iodide a faster overall reaction meant that discrimination between the two processes was less clear. Instantaneous sorption of IO3- was greater in soils with high Fe/Mn oxide content, low pH and low SOC content, whereas the rate of time-dependent sorption was greatest in soils with higher SOC contents. Phosphate extraction (0.15 M KH2PO4) of soils, ∼100 h after 129I spike addition, indicated that concentrations of sorbed inorganic iodine (129I) were very low in all soils suggesting that inorganic iodine adsorption onto oxide phases has little impact on the rate of iodine assimilation into humus. Transformation of dissolved inorganic 129IO3- and 129I− to sorbed organic forms was modelled using a range of reaction- and diffusion-based approaches. Irreversible and reversible first order kinetic models, and a spherical diffusion model, adequately described the kinetics of both IO3- and I− loss from the soil solution but required inclusion of a distribution coefficient (kd) to allow for instantaneous adsorption. A spherical diffusion model was also collectively parameterised for all the soils studied by using pH, soil organic carbon concentration and combined Fe + Mn oxide content as determinants of the model parameters (kd and D/r2). The kinetic model parameters were not directly related to a single soil parameter; inclusion of pH, SOC, oxide content and temperature was necessary to describe the observed behaviour. From the temperature-dependence of the sorption data the activation energy (Ea) for 129IO3- transformation to organic forms was estimated to be ∼43 kJ mol−1. The Ea value was independent of %SOC and was consistent with a reaction mechanism slower than pore diffusion or physical adsorption, but faster than most surface reactions.

ACS Style

W.H. Shetaya; S.D. Young; M.J. Watts; E.L. Ander; E.H. Bailey. Iodine dynamics in soils. Geochimica et Cosmochimica Acta 2011, 77, 457 -473.

AMA Style

W.H. Shetaya, S.D. Young, M.J. Watts, E.L. Ander, E.H. Bailey. Iodine dynamics in soils. Geochimica et Cosmochimica Acta. 2011; 77 ():457-473.

Chicago/Turabian Style

W.H. Shetaya; S.D. Young; M.J. Watts; E.L. Ander; E.H. Bailey. 2011. "Iodine dynamics in soils." Geochimica et Cosmochimica Acta 77, no. : 457-473.