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Cunha, K. Dias da; Lipsztein, J. L.; Azeredo, A. M. G. F.; Melo, Dunstana R.; Julião, L. M. Q. C.; Lamego, Fernando; Santos, M.; Leite, C. V. Barros

doi:10.1023/a:1015599406550

Cited by 9 publications

(6 citation statements)

References 10 publications

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“…The concentration levels found for most heavy metals in Salina Cruz were in the range of recent observations at Mexican [5,17] and other Latin American (e.g. [18]) and European (e.g. [6,8,[19][20][21]) urban sites, but below the levels found nowadays at urban sites in China (e.g.…”

Section: Mass Concentrations and Influences Of Possible Sourcescontrasting

confidence: 59%

“…For many elements, the number of samples determined is much smaller than the total number of samples (18), because the concentration could not be determined in one or more of the impactor stages. Listed are the results from complete sets of determinations across the four impactor stages as well as sets consisting of determinations from three stages, when either impactor stage 1 or 4 (those with the lowest concentrations), but not both, could not be determined.…”

Section: Mass Concentrations and Influences Of Possible Sourcesmentioning

confidence: 99%

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Evolution of anthropogenic aerosols in the coastal town of Salina Cruz, Mexico: part III size-segregated elemental composition analysed by total-reflection X-ray fluorescence spectrometry

Lammel

Baumgardner

Fittschen

et al. 2007

International Journal of Environmental Analytical Chemistry

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Heavy metals in various size modes of the atmospheric aerosol are a concern for human health. Their and other elements' concentrations are indicative for anthropogenic and natural aerosol sources. Si, Cl, K, Ca, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Br, Rb, Sr, Hg, and Pb were determined as a complementary contribution to a study on aerosol cycling during the wet season, June 2004, in a humid, subtropical climate, i.e. in the city of Salina Cruz, situated on the Pacific coast of the Isthmus of Tehuantepec (16.2 N, 95.2 W), Mexico. For mass (gravimetry) and elemental analyses, particles were collected by a Berner low-pressure round nozzle cascade impactor using four stages corresponding to 0.1-0.25, 0.25-1.0, 1.0-4.0, and 4-16 mm of aerodynamic particle size. The impaction plates were modified such that approx. 1/6 consisted of a plastic support (Persplex Õ ) for total reflection X-ray fluorescence spectrometry (TXRF). The elements' total content was determined by TXRF without any further sample pretreatment. Limits of quantification (LOQ) for elemental content in individual impactor stages corresponded to 25-60 ng m À3 for Si; 0.8-4 ng m À3 for Cl, K, Ca, Ti, and V; 3-20 pg m À3 for Cr, Mn, Fe, Cu, Ni, and Zn; and 7-50 pg m À3 for As, Se, Br, Rb, Sr, Hg, and Pb. In some samples, however, high blank values for the supports gave an LOQ ¼ 6-19 ng m À3 for Cl; 3-7 ng m À3 for Ca; 3-7 ng m À3 for Fe, Ni, Cu, and Zn; and 60-70 ng m À3 for Pb. The influence of local natural, industrial, and vehicle traffic sources for heavy-metal mobilization was obvious. Heavy-metal abundances did not coincide with regionally distributed pollutants. V and Ni were found at particularly elevated levels advected with the sea breeze, which points to ships as sources. Br and Pb were found at particularly low levels. The concentrations of Br, Rb, Sr, and Pb were found below LOQ at least in some, As, Co, Se, and Hg in all of the samples. The elements' characteristic differences in mass size distributions were obvious despite the coarse size resolution. During the cycling of air masses from land to sea and back again, enrichment of super-micrometre particles in the near ground aerosol was observed under dry weather conditions. Rain preferentially removed the large particles with which heavy metals have been associated. *Corresponding

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Section: Mass Concentrations and Influences Of Possible Sourcescontrasting

confidence: 59%

Section: Mass Concentrations and Influences Of Possible Sourcesmentioning

confidence: 99%

Evolution of anthropogenic aerosols in the coastal town of Salina Cruz, Mexico: part III size-segregated elemental composition analysed by total-reflection X-ray fluorescence spectrometry

Lammel

Baumgardner

Fittschen

et al. 2007

International Journal of Environmental Analytical Chemistry

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“…In the Brazilian plant, the workers were exposed to uranium-bearing particles in the respirable fraction of aerosols and there is some data in literature about worker exposure in this plant (Dias da Cunha et al 2002;Oliveira 2006). The specific parameters of uranium solubility determined in the present study were used to predict the uranium concentration in urine and feces samples from workers involved in mining and milling processes.…”

Section: In Vitro Solubility Testmentioning

confidence: 99%

“…In order to predict U concentration in excreta samples, it was used as commercially available computer program (activity and internal dose estimation, AIDE; Bertelli et al 2008) samples from worker exposed, it was considered inhalation as the only way of intake, particle size (activity median aerodynamic diameter) equal to 1.5 μm (Dias da Cunha et al 2002), the specific time of exposure for each worker (Oliveira 2006), and the ICRP solubility parameters for uranium oxides (f r = 0.001, λ r =100 day −1 , and λ s =0.0001 day −1 ) and the parameters proposed for pyrochlore in this study. The values of uranium concentration in urine and feces were predicted using the AIDE program assuming our solubility parameters and the solubility parameters provide by ICRP for uranium oxides (f r = 0.001, λ r =100 day −1 , and λ s =0.0001 day −1 ).…”

Section: In Vitro Solubility Testmentioning

confidence: 99%

“…Biokinetic behavior of several compounds of Th and U are well known (International Commission on Radiological Protection (ICRP) 1959, publication no. 2), but there is little data about the biokinetic behavior of Th and U associated to mineral crystal lattice (Dias da Cunha et al 2002;Wan et al 2006;Stradling et al 2003;Sutton and Burastero 2004;Chen et al 2005;Li et al 2007). While there are available several data about the effects of Th and U in the human body, there is very few data about Ta toxicity and these few studies are not conclusive.…”

Section: Introductionmentioning

confidence: 99%

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Dissolution Factors of Ta, Th, and U Oxides Present in Pyrochlore

Cunha

Santos

Zouain

et al. 2009

Water Air Soil Pollut

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Air pollution can be a problem in industrial processes, but monitoring and controling the aerosols in the work place is not enough to estimate the occupational risk due to dust particle inhalation. The solubility in lung fluid is considered to estimate this risk. The aim of this study is to determine in vitro specific dissolution parameters for thorium (Th), uranium (U), and tantalum (Ta) associated to crystal lattice of a niobium mineral (pyrochlore). Th, U, and Ta dissolution factors in vitro were obtained using the Gamble solution (simulant lung fluid, SLF), particle induced X-ray emission, and alpha spectrometry as analytical techniques. Ta, Th, and U are present in the pyrochlore crystal lattice as oxide; however, they have shown different dissolution parameters. The rapid dissolution fraction (f r ), rapid dissolution rate (λ r ), slow dissolution rate (f s ), and slow dissolution fraction (λ s ) measured for tantalum oxide were equal to 0.1 and 0.45 and 0.00007 day −1 , respectively. For uranium oxide, f r was equal to 0.05, λ r was equal to 1.1 day −1 , and λ s was equal to 0.000068 day −1 . For thorium oxide, f r was 0.025, λ r was 1.5 day −1 , and λ s was 0.000065 day −1 . These results show that chemical behavior of these three compounds in the SLF could not be represented by the same parameter. The ratio of uranium concentration in urine and feces samples from workers exposed to pyrochlore dust particle was determined. These values agree with the theoretical values of estimated uranium concentration using specific parameters for uranium oxide present in pyrochlore.

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Geochemical assessment, distribution, and dynamics of trace elements in urban agricultural soils under long‐term wastewater irrigation in Kano, northern Nigeria

Abdu

Agbenin

Buerkert

2011

Z. Pflanzenernähr. Bodenk.

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A study was conducted to evaluate the distribution and origin of trace elements (Ti, Fe, Nb, Pb, Rb, Sr, Y, and Zr) in five representative long‐term wastewater‐irrigated urban vegetable gardens of Kano, Nigeria. Surface‐soil concentrations (0–15 cm) of Ti (4600–14 300 mg kg–1), Fe (4000–31 800 mg kg–1), Pb (96–355 mg kg–1), and Y (33–98 mg kg–1) were high compared to mean concentrations in comparable soils elsewhere. However, soil‐pollution assessment yielded no evidence of anthropogenic input of the trace elements studied. Indices such as the enrichment factor, the contamination factor, and the geoaccumulation index (Igeo) revealed little to no contamination with trace elements. The Igeo calculated for these metals varied across locations between 0.00 and 0.12 with Nb having the highest Igeo value. Similarly, the contamination factor was low for all metals with the exception of Fe reaching a contamination factor of 4.2 at one location. Geochemical‐balance evaluations showed depletion of all trace elements except for Fe which was 176% higher than in a natural uncultivated and unirrigated reference soil. Correlation and factor analyses showed that all determined trace elements likely originated from the same natural sources, which probably are the soil parent material and atmospheric depositions.

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Cited by 9 publications

References 10 publications

Evolution of anthropogenic aerosols in the coastal town of Salina Cruz, Mexico: part III size-segregated elemental composition analysed by total-reflection X-ray fluorescence spectrometry

Evolution of anthropogenic aerosols in the coastal town of Salina Cruz, Mexico: part III size-segregated elemental composition analysed by total-reflection X-ray fluorescence spectrometry

Dissolution Factors of Ta, Th, and U Oxides Present in Pyrochlore

Geochemical assessment, distribution, and dynamics of trace elements in urban agricultural soils under long‐term wastewater irrigation in Kano, northern Nigeria

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