Arsenic

Assessment of the Exposure to Arsenic and Fluoride from Drinking Water in the City of Guadalupe, Zacatecas, Mexico.

by Osiel González Dávila

The paper "Assessment of the Exposure to Arsenic and Fluoride from Drinking Water in the City of Guadalupe, Zacatecas, Mexico" was presented at the World Congress on Water, Climate and Energy organised by the International Water Association (IWA-WCE 2012) in Dublin on May 15, 2012.

González Dávila, O. (2012) Assessment of the Exposure to Arsenic and Fluoride from Drinking Water in the City of Guadalupe, Zacatecas, Mexico. World Congress on Water, Climate and Energy. International Water Association.

In several areas of Northern Mexico, groundwater arsenic and fluoride levels above the limits established by the... more In several areas of Northern Mexico, groundwater arsenic and fluoride levels above the limits established by the Mexican guideline have been detected. An exploratory study found that in two of the extraction wells from the system that provides water to the city of Guadalupe, Zacatecas, the levels of arsenic were 10 and 16 times above the Mexican guideline. Further, the fluoride levels were two times above the guideline. There was an urgent need to characterize the risk areas for arsenic and fluoride exposure. In this study arsenic and fluoride exposures from drinking water were estimated and different risk areas in the city of Guadalupe were identified and mapped. It was found that 100% of the collected samples show levels of arsenic above the Mexican guideline of 0.025 mg/l arsenic and almost 50% of the samples have levels of fluoride above the 1.5 mg/l fluoride guideline. Women and children 0-12 years old were identified as particularly vulnerable groups. A comprehensive public policy is required to tackle this environmental problem.
Keywords: Arsenic, Fluoride, Mexico, Water Contamination

Speciation of Arsenic, Chromium, and Vanadium in Red Mud Samples from the Ajka Spill Site, Hungary

by William Mayes

Burke, I.T., Mayes, W.M., Peacock, C.L., Brown, A.P., Jarvis, A.P., Gruiz, K. (2012) Speciation of arsenic, chromium and vanadium in red mud samples from the Ajka spill site, Hungary. Environmental Science and Technology. doi: 10.1021/es3003475.

Results are presented from X-ray absorption spectroscopy based analysis of As, Cr and V speciation within samples of... more Results are presented from X-ray absorption spectroscopy based analysis of As, Cr and V speciation within samples of bauxite ore processing residue (red mud) collected from the spill site at Ajka, Western Hungary. Cr K-edge XANES analysis found that Cr is present as Cr3+ substituted into hematite, consistent with TEM analysis. V K-edge XANES spectra have E½ position and pre-edge features consistent with the presence of V5+ species, possibly associated with Ca-aluminosilicate phases. As K-edge XANES spectra identified As present as As5+. EXAFS analysis reveals arsenate phases in red mud samples. When alkaline leachate from the spill site is neutralised with HCl, 94 % As and 71 % V is removed from solution during the formation of amorphous Al-oxyhydroxide. EXAFS analysis of As in this precipitate reveals the presence of arsenate Al-oxyhydroxide surface complexes. These results suggest that in the circumneutral pH, oxic conditions found in the Torna and Upper Marcal catchments, incorporation and sorption respectively will restrict the environmental mobility of Cr and As. V is inefficiently removed from solution by neutralisation, therefore, the red mud may act as a source of mobile V5+ where the red mud deposits are not removed from affected land.

Plants and Soil Contamination with Heavy Metals in Agricultural Areas of Guadalupe, Zacatecas, Mexico

by Osiel González Dávila

The article "Plants and Soil Contamination with Heavy Metals in Agricultural Areas of Guadalupe, Zacatecas, Mexico" has been published as book chapter:

Osiel González Dávila, Juan Miguel Gómez-Bernal and Esther Aurora Ruíz-Huerta (2012). Plants and Soil Contamination with Heavy Metals in Agricultural Areas of Guadalupe, Zacatecas, Mexico, Environmental Contamination, Jatin Kumar Srivastava (Ed.), ISBN: 978-953-51-0120-8, InTech, Available from: http://www.intechopen.com/articles/show/title/plants-and-soil-contamination-with-heavy-metals-in-agricultural-areas-of-guadalupe-zacatecas-mexico

A geochemical comparative study was conducted in the municipality of Guadalupe in Zacatecas, Mexico. The objectives... more A geochemical comparative study was conducted in the municipality of Guadalupe in Zacatecas, Mexico. The objectives were to measure the bioconcentration factor in maize plants in function of their heavy metal absorption, to identify the toxicity order of heavy metals in plants of agronomic interest, to assess potential environmental impacts taking into account the particularities of the selected crop and to evaluate the potential consequences on the region’s food security. High levels of arsenic, lead and mercury contamination in agricultural soil were found in two irrigation zones. High levels of Zn and Cu were found both in soils and plants in all the areas.
Heavy metal absorption in maize plants aimed for human consumption was calculated using the bioconcentration and the translocation factors. The accumulation of Pb and As
in plants was very high. Those metals are highly toxic and could be bioaccumulated and transferred to the food chain. Further, high levels of Zn and Cu were found both in soils and plants. Although they are not considered toxic for humans, they are toxic for plants. These elements hinder the development of plants and could reduce land productivity.

Influence of hardpan layers on arsenic mobility in historical gold mine tailings

by Stephanie DeSisto

Inorganic Arsenic and Basal Cell Carcinoma in Areas of Hungary, Romania, and Slovakia: A Case-Control Study.

by Giovanni Leonardi

Leonardi G, Vahter M, Clemens F, Goessler W, Gurzau E, Hemminki K, Hough R, Koppova K, Kumar R, Rudnai P, Surdu S, Fletcher T. Inorganic Arsenic and Basal Cell Carcinoma in Areas of Hungary, Romania, and Slovakia: A Case-Control Study. Environ Health Perspect:120:721–726 (2012). http://dx.doi.org/10.1289/ehp.1103534 [Online 31 January 2012]

Biomonitoring of trace elements in the leaves and fruits of wild olive and holm oak trees

by Teodoro Marañón

Science of Total Environment 355: 187-203 (2006)

Biomonitoring of trace elements is essential to assess ecosystem health, in particular in landscapes influenced by... more Biomonitoring of trace elements is essential to assess ecosystem health, in particular in landscapes influenced by human activity. The Guadiamar Valley (SW Spain) was polluted in 1998 by a spill from an open-pit pyrite mine affecting about 55 km2. In this paper, we used two common species of tree, namely wild olive and holm oak, to biomonitor the concentration of nine trace elements–As, Cd, Cu, Fe, Mn, Ni, Pb, Tl and Zn–in this spill-affected area over the 3-year period 1999–2001. We analysed the leaves and fruits of trees growing in the spill-affected terraces, and compared them with adjacent trees in the non-affected upper terraces. The main trace elements polluting the soil were Zn, As, Pb and Cu. In general, the oak leaves were richer in trace elements than the olive leaves, reaching phytotoxic levels for As and Pb, while the olive fruits (pulp) were more polluted than the oak seeds (protected inside a hard pericarp), reaching toxic values for Cd and Pb. The concentration of trace elements in the leaves and fruits decreased with time and, in consequence, the toxicity risk to the food web diminished.

Arsenate Incorporation in Gypsum Probed by Neutron, X-ray Scattering and Density Functional Theory Modeling

by Alejandro Fernandez-Martinez

White poplar (Populus alba) as a biomonitor of trace elements in contaminated riparian forests

by Teodoro Marañón

Environmental Pollution 32: 145-155 (2004)

Trees can be used to monitor the level of pollution of trace elements in the soil and atmosphere. In this paper, we... more Trees can be used to monitor the level of pollution of trace elements in the soil and atmosphere. In this paper, we surveyed the content of eight trace elements (As, Cd, Cu, Fe, Mn, Ni, Pb and Zn) in leaves and stems of white poplar (Populus alba) trees. We selected 25 trees in the riparian forest of the Guadiamar River (S. Spain), one year after this area was contaminated by a mine spill, and 10 trees in non-affected sites. The spill-affected soils had significantly higher levels of available cadmium (mean of 1.25 mg kg−1), zinc (117 mg kg−1), lead (63.3 mg kg−1), copper (58.0 mg kg−1) and arsenic (1.70 mg kg−1), than non-affected sites. The concentration of trace element in poplar leaves was positively and significantly correlated with the soil availability for cadmium and zinc, and to a lesser extent for arsenic (log–log relationship). Thus, poplar leaves could be used as biomonitors for soil pollution of Cd and Zn, and moderately for As.

Afforestation of a trace-element polluted area in SW Spain: woody plant performance and trace element accumulation

by Teodoro Marañón

European Journal of Forest Research 129: 47-59 (2010)

Trace element soil pollution can have ecotoxic effects on plants, which could negatively affect the restoration of a... more Trace element soil pollution can have ecotoxic effects on plants, which could negatively affect the restoration of a degraded area. In this work, we studied the revegetation success in different sites within a trace element-polluted area (Guadiamar River Valley, SW Spain). We analysed the survival and growth patterns of afforested plants of seven Mediterranean woody species, and their relation to soil pollution, over 3 years. We also analysed the trace element accumulation in the leaves of these species. The area was polluted mainly by As, Cd, Cu, Pb and Zn (soil total concentrations up to 250, 3.6, 236, 385 and 510 mg kg−1, respectively). The woody plant performance was very different between sites and between species; in the riparian sites, plant survival rates were nearly 100%, while in the upland terrace sites species such as Quercus ilex and Ceratonia siliqua showed the lowest survival rates (less than 30%) and also the lowest relative growth rates. There were no significant relationships between plant performance and soil pollution in the riparian sites, while in the upland sites mortality, but not growth, was related to soil pollution, although that could be an indirect effect of different substrate alteration between sites. The accumulation of soil pollutants in the studied plants was low, with the exception of Salicaceae species, which accumulated Cd and Zn in the leaves above 1 and 200 mg kg−1, respectively. We discuss the results with regard to the afforestation of trace-element polluted areas.

Impacts of epigeic, anecic and endogeic earthworms on metal and metalloid mobility and availability

by Tom Sizmur

Earthworms increase the mobility and availability of As, Cu, Pb and Zn in a contaminated soil.

The introduction of earthworms into soils contaminated with metals and metalloids has been suggested to aid... more The introduction of earthworms into soils contaminated with metals and metalloids has been suggested to aid restoration practices. Eisenia veneta (epigeic), Lumbricus terrestris (anecic) and Allolobophora chlorotica (endogeic) earthworms were cultivated in columns containing 900 g soil with 1130, 345, 113 and 131 mg kg−1 of As, Cu, Pb and Zn, respectively, for up to 112 days, in parallel with earthworm-free columns. Leachate was produced by pouring water on the soil surface to saturate the soil and generate downflow. Ryegrass was grown on the top of columns to assess metal uptake into biota. Different ecological groups affected metals in the same way by increasing concentrations and free ion activities in leachate, but anecic L. terrestris had the greatest effect by increasing leachate concentrations of As by 267%, Cu by 393%, Pb by 190%, and Zn by 429% compared to earthworm-free columns. Ryegrass grown in earthworm-bearing soil accumulated more metal and the soil microbial community exhibited greater stress. Results are consistent with earthworm enhanced degradation of organic matter leading to release of organically bound elements. The degradation of organic matter also releases organic acids which decrease the soil pH. The earthworms do not appear to carry out a unique process, but increase the rate of a process that is already occurring. The impact of earthworms on metal mobility and availability should therefore be considered when inoculating earthworms into contaminated soils as new pathways to receptors may be created or the flow of metals and metalloids to receptors may be elevated.

Impact of gut passage and mucus secretion by the earthworm Lumbricus terrestris on mobility and speciation of arsenic in contaminated soil

by Tom Sizmur

Highlights

► Passage through the earthworm gut increased water soluble arsenic.
► 56-Day aged casts still contained more than nine times greater water soluble As.
► Changes were due to increases in As(V) mobility, with no change in As(III).
► Dilute mucus reduced As mobility due to As–amino acid–Fe–OH ternary complexes.
► Impact of earthworms on As mobility should be considered in risk assesment.

Earthworms inhabiting arsenic contaminated soils may accelerate the leaching of As into surface and ground waters. We... more Earthworms inhabiting arsenic contaminated soils may accelerate the leaching of As into surface and ground waters. We carried out three experiments to determine the impact of passage of As contaminated soil (1150 mg As kg−1) through the gut of the earthworm Lumbricus terrestris on the mobility and speciation of As and the effects of earthworm mucus on As mobility. The concentration of water soluble As in soil increased (from 1.6 to 18 mg kg−1) after passage through the earthworm gut. Casts that were aged for 56 days still contained more than nine times greater water soluble As than bulk earthworm inhabited soil. Changes were due to increases in As(V) mobility, with no change in As(III). Dilute mucus extracts reduced As mobility through the formation of As–amino acid–iron oxide ternary complexes. More concentrated mucus extracts increased As mobility. These changes, together with those due to the passage through the gut, were due to increases in pH, phosphate and soluble organic carbon. The mobilisation of As from contaminated soils in the environment by cast production and mucus secretion may allow for accelerated leaching or uptake into biota which is underestimated when bulk soil samples are analysed and the influence of soil biota ignored.

Fractionation and Bioavailability of Arsenic in the Bed Sediments of the Anllóns River (NW Spain)

by Remigio Paradelo

Water, Air & Soil Pollution (2008). Co-authored with R. Devesa-Rey, F- Díaz-Fierros & M.T. Barral.

The arsenic bioavailability in the bed sediments from the Anllóns River (NW Spain) has been assessed by using several... more The arsenic bioavailability in the bed sediments from the Anllóns River (NW Spain) has been assessed by using several analytical approaches. A six-step sequential fractionation was compared to three general availability tests: the Toxicity Characteristic Leaching Procedure (TCLP) extraction, which estimates the leaching potential of As and its effect on the survival of microorganisms (Vibrio fischeri), an extraction with 1 M HCl extraction, which estimates the bioavailability to higher plants, and a physiologically based extraction test (PBET), which estimates the bioavailability to superior animals. Arsenic was found to be mainly associated to the least mobile fractions: bound to Fe-Al oxides and in the residual phase. Among the three single extractants considered, the PBET extracted the highest As concentrations (1–11% of the total As). The TCLP extracts showed toxicity to Vibrio fischeri whereas for the plants evaluated, aqueous extracts did not show adverse effects.

Interpretation of drinking water quality guidelines--The case of arsenic

by Michael Silberbauer

WaterSA, Vol. 33, No. 1. (2007), pp. 95-100. by PL Kempster, M Silberbauer, A Kühn

Drinking water quality guidelines are often interpreted by the non-expert as make or break cut-off values below which... more Drinking water quality guidelines are often interpreted by the non-expert as make or break cut-off values below which drinking water is absolutely safe, and above which it is totally unacceptable. In reality there is no such knifelike cut-off limit, and there is a large grey area between safe water and undrinkable water. The uncertainty of the boundaries of the grey area for each constituent presents a serious problem, both in the creation of sound drinking water quality guidelines or standards, and in the problem of how to interpret the risk to human health when guideline values are exceeded. In this paper this problem is discussed using the case of arsenic, where the definition of the boundaries of the grey area is particularly uncertain.

Keywords: drinking water quality, guideline interpretation, arsenic, uncertainties

Electrocoagulation as a tertiary treatment for paper mill wastewater: Removal of non-biodegradable organic pollution and arsenic

by Jean-Noël Louvet

Sources and controls of Arsenic contamination in groundwater of Rajnandgaon and Kanker District, Chattisgarh Central India

by Dericks Shukla

Factors influencing the metabolite pattern of urinary arsenic following exposure via drinking water

by Giovanni Leonardi

Lindberg, A.L.; Goessler, W.; Leonardi, G.; Rahman, M.; Person, L.A.; Ekstrom, E.C.; Kumar, R.; Vahter, M.
Toxicology Letters, 2006; 164:S199-S200

IC-ICP-MS and IC-ICP-HEX-MS determination of arsenic speciation in surface and groundwaters: preservation and analytical issues

by Miltiadis Nimfopoulos

Authors: D.A. Polya, P. Lythgoe, F. Abou-Shakra, A. Gault, J. R. Brydie, J.G. Webster, K.L. Brown, M.K. Nimfopoulos, K.M. Michailidis
Mineralogical Magazine 67(2), 247-261/Mineralogical Society UK, 2003

Understanding the biogeochemical behaviour of arsenic in the weathering and shallow subsurface environment depends... more Understanding the biogeochemical behaviour of arsenic in the weathering and shallow subsurface environment depends critically upon determining the nature and distribution of the chemical species present in natural waters. To this end, coupled ion chromatography-inductively coupled plasma mass spectrometry (IC-ICP-MS) is widely used, though species fractionation during ultrasonic nebulization, and matrix-dependent ionization in the plasma are analytical issues that need to be addressed. Hexapole collision cell technology is shown to be effective in suppressing chloride-based polyatomic interferences. Irrespective of the analytical technique used, As(III)/As(V) ratios of natural waters may change substantially during storage due to (1) differential adsorption of arsenic species on hydrated ferric oxides (HFOs); and (2) microbial activity. A wide range of apparently contradictory speciation changes observed by various workers can be rationalized in terms of the differences of microbial consortia present in different water samples. Arsenic speciation in certain water types can be stabilized for days or even weeks by combined filtration, acidification and refrigeration whilst the addition of EDTA and the use of 0.1 µm filters is indicated for iron-rich waters and waters with high activities of redox-active bacteria, respectively. Although the use of hydrochloric acid has been reported elsewhere as resulting in the apparent oxidation of As(III), we show that for certain water types it acts as an extremely effective preservative of arsenic speciation.

Estimating Previous Exposure to Arsenic for Populations Living in Parts of Hungary, Romania and Slovakia.

by Giovanni Leonardi

Reference:

Hough, R.L., Leonardi, G.S. & Fletcher, T. Estimating Previous Exposure to Arsenic for Populations Living in Parts of Hungary, Romania and Slovakia. In: Natural Arsenic in Groundwater (Eds. J. Bundschuh, P. Bhattacharya, D. Chandrasekharam). Taylor and Francis, London, 2005.

ISBN 041536700X

GEOSPECIATION OF ARSENIC USING MINTEQA2 FOR A POST-MINING LAKE

by Umi Ahmad

PUBLISHED IN WATER SCIENCE AND TECHNOLOGY, VOL 54, NO 11-12, PP 288-299

Voltammetric determination of arsenic in high iron and manganese groundwaters

by pascal salaun