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1.
Chemosphere ; 337: 139385, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37394189

RESUMEN

Mercury-thallium mining waste slag has the characteristics of extremely acidic, low fertility and highly toxic polymetallic composite pollution, making it difficult to be treated. We use nitrogen- and phosphorus-rich natural organic matter (fish manure) and calcium- and phosphorus-rich natural minerals (carbonate and phosphate tailings) individually or in combination to amend the slag, analyze their effects on the migration and transformation of potentially toxic elements (Tl and As) in the waste slag. We set up sterile and non-sterile treatments specifically to further investigate the direct or indirect effect of microorganisms attached to added organic matter on Tl and As. The results showed that addition of fish manure and natural minerals to the non-sterile treatments promoted the release of As and Tl, resulting in an increase in As and Tl concentrations in the tailing lixiviums from 0.57 to 2.38-6.37 µg/L and from 69.92 to 107.51-157.21 µg/L, respectively. Sterile treatments promoted the release of As (from 0.28 to 49.88-104.18 µg/L) and inhibited the release of Tl (from 94.53 to 27.60-34.50 µg/L). Use of fish manure and natural minerals alone or in combination significantly reduced the biotoxicity of the mining waste slag, in which the combination was more efficient. XRD analysis showed that microorganisms in the medium promoted the dissolution of jarosite and other minerals, which indicated that the release and migration of As and Tl in Hg-Tl mining waste slag were closely related to microbial activities. Furthermore, metagenomic sequencing revealed that microorganisms such as Prevotella, Bacteroides, Geobacter, and Azospira, which were abundant in the non-sterile treatments, had remarkable resistance to a variety of highly toxic heavy metals and could affect the dissolution of minerals and the release and migration of heavy metals through redox reactions. Our results may aid in the rapid soilless ecological restoration of related large multi-metal waste slag dumps.


Asunto(s)
Mercurio , Metales Pesados , Talio/análisis , Estiércol , Metales Pesados/análisis , Minerales/análisis , Fósforo
2.
Chemosphere ; 307(Pt 4): 136150, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36028131

RESUMEN

Benthic bioaccumulation of hazardous materials has been a great challenge to the health of lake ecosystems. As representative benthic macroinvertebrates, freshwater mussels and their accumulation characteristics have been regarded as effective indicators for assessing potential risks induced by sedimentary metal(loid)s in lakes. Here we profile organ-specific accumulation of 35 metal(loid)s in a freshwater mussel (Hyriopsis cumingii) and their correlations to metal speciation in sediments of Poyang Lake, the largest lake of China. Significant organ-specific characteristics of metal accumulation were found in gills, though higher thallium (Tl) and selenium (Se) were found in the hepatopancreas, and greater arsenic (As) mostly accumulated in gonads. Pearson correlation analysis revealed that the bioaccumulation of silver (Ag), cobalt (Co), and rare earth elements (ΣREE) in gills and As in gonads were closely associated with those in bioavailable fraction of sediments. Based on the biochemical analysis in the major organs, gills exhibited the highest enzymatic activity compared with hepatopancreas and gonads. Sedimentary metals, particularly for available Ag, Co, and ΣREE, play key roles in causing lipid peroxidation in gills and significantly promote the activities of superoxide dismutase (SOD)/glutathione reductase (GR), while many metals (e.g., cadmium, manganese, Se) inhibit the glutathione (GSH) content in gonads and hepatopancreas. Our study indicates a high physiological sensitivity of mussels to these target metals, which highlights the significance of organ-specific accumulation of metal(loid)s in understanding the potential ecological risks of sedimentary metal(loid)s in lake ecosystems.


Asunto(s)
Arsénico , Bivalvos , Metales Pesados , Selenio , Unionidae , Contaminantes Químicos del Agua , Animales , Arsénico/análisis , Bioacumulación , Cadmio/análisis , Cobalto/análisis , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos/química , Glutatión , Glutatión Reductasa , Sustancias Peligrosas/análisis , Lagos/química , Manganeso/análisis , Metales Pesados/análisis , Selenio/análisis , Plata/análisis , Superóxido Dismutasa , Talio/análisis , Contaminantes Químicos del Agua/análisis
3.
Environ Sci Pollut Res Int ; 29(40): 60269-60277, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35419687

RESUMEN

Human beings are exposed to heavy metals through various ways in daily life. However, the effect of heavy metal mixtures on muscle strength in children and adolescents remains unclear. We aimed to investigate the relationship of exposure to heavy metal mixtures (barium, cadmium, cobalt, manganese, molybdenum, lead, antimony, strontium, tin, thallium, tungsten, uranium, and cesium) with muscle strength in children and adolescents. A total of 1357 (boys, 50.8%) participants aged between 8 and 17 were extracted from the National Health and Nutrition Examination Surveys 2011-2014. Urine metals were measured by inductively coupled plasma-mass spectrometry. Muscle strength was measured through a grip test using a handgrip dynamometer. Weighted quantile sum regression was performed to estimate the mixture effect of urinary metals on muscle strength. After adjusting for potential confounders, comparing participants in the highest versus lowest quartiles of cobalt, molybdenum, lead, antimony, strontium, thallium, and cesium, the handgrip strength decreased by - 4.48 kg (95% CI: - 6.93, - 2.03), - 6.13 kg (- 8.76, - 3.51), - 2.26 kg (- 4.22, - 0.30), - 2.38 kg (- 4.68, - 0.08), - 2.29 kg (- 4.45, - 0.13), - 4.78 kg (- 7.13, - 2.44), and - 5.68 kg (- 9.20, - 2.17), respectively. Furthermore, exposure to a mixture of metals were also significantly associated with decreased muscle strength (ß: - 2.62 kg; 95% CI: - 3.71, - 1.54). Findings from the present study suggest that higher heavy metal exposure and the exposure levels of a mixture of metals in urine are inversely related to handgrip strength, implying that children's grip strength is not entirely explained by energy intake or lack of exercise, but may be related to environmental pollutants.


Asunto(s)
Metales Pesados , Uranio , Adolescente , Antimonio/análisis , Cesio/análisis , Niño , Cobalto/análisis , Exposición a Riesgos Ambientales/análisis , Fuerza de la Mano , Humanos , Masculino , Metales Pesados/análisis , Molibdeno/análisis , Estroncio/análisis , Talio/análisis , Uranio/análisis
4.
J Hazard Mater ; 407: 124402, 2021 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-33189469

RESUMEN

Thallium (Tl) pollution caused by the exploitation of uranium (U) mines has long been neglected due to its low crustal abundance. However, Tl may be enriched in minerals of U ore because Tl has both sulfurophile and lithophile properties. Herein, a semi-dynamic leaching experiment combined with statistical analysis, geochemical speciation and multi-characterization provided novel insight into the distinct features and mechanisms of Tl release from uranium mill tailings (UMT). The results showed that particle size effects prevail over the pH on Tl release, and surface dissolution is the pivotal mechanism controlling Tl release based on Fick's diffusion model. The study revealed that long-term leaching and weathering can lead to the increased acid-extractable and oxidizable fractions of Tl in UMT, and that the exposure and dissolution of Tl-containing sulfides would largely enhance the flux of Tl release. The findings indicate that UMT containing (abundant) pyrite should be paid particular attention due to Tl exposure. Besides, critical concern over the potential Tl pollution in universal U mining and hydrometallurgical areas likewise may need to be seriously reconsidered.


Asunto(s)
Contaminantes Radiactivos del Suelo , Uranio , Contaminantes Radiactivos del Agua , Minería , Talio/análisis , Uranio/análisis , Contaminantes Radiactivos del Agua/análisis
5.
Ecotoxicol Environ Saf ; 195: 110475, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-32208212

RESUMEN

Risk assessment regarding heavy metals in tea is crucial to ensure the health of tea customers. However, the effects of geological difference on distribution of heavy metals in soils and their accumulation in tea leaves remain unclear. This study aimed to estimate the impacts of geological difference on distribution of cadmium (Cd), lead (Pb), thallium (Tl), mercury (Hg), arsenic (As), antimony (Sb), chromium (Cr), nickel (Ni), and manganese (Mn) in soils and their accumulation in tea leaves, and further evaluate their health risks. 22 soils and corresponding young tea leaves (YTL) and old tea leaves (OTL), from geologically different plantations, were sampled and analyzed. Results showed that heavy metals concentrations in soils, derived from Permian limestone and Cambrian weakly mineralized dolomite, were obviously greater than those from Silurian clastic rock. The geological difference controlled the distribution of soil heavy metals to a large extent. Contents of Cd, Tl, and Mn in tea leaves mainly depended on their contents in soils. Soil Hg, Pb, As, and Sb contents may not be the only influencing factors for their respective accumulation in tea leaves. More attentions should be paid to soil acidification of tea plantations to ensure the tea quality security. Target hazard quotients (THQ) of Cd, Pb, Tl, Hg, As, Sb, Cr, and Ni and hazard index (HI) via tea intake were below one, indicating no human health risk. The non-mineralized Silurian area was less at risk of heavy metals accumulation in tea leaves than the Cambrian metallogenic belt and the Permian Cd-enriched zone. This study could provide an important basis to understand and mitigate the potential risks of heavy metals in tea.


Asunto(s)
Metales Pesados/análisis , Contaminantes del Suelo/análisis , Té/química , Antimonio/análisis , Arsénico/análisis , Cadmio/análisis , China , Cromo/análisis , Monitoreo del Ambiente , Fenómenos Geológicos , Humanos , Plomo/análisis , Manganeso/análisis , Mercurio/análisis , Níquel/análisis , Hojas de la Planta/química , Medición de Riesgo , Suelo/química , Talio/análisis
6.
Hum Exp Toxicol ; 39(6): 808-815, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32009467

RESUMEN

CONTEXT: Heavy metals, including thallium and lead, are introduced to illicit drug users' body as a result of using drugs such as cocaine and heroin. OBJECTIVE: This study aimed to determine urine, blood, and hair thallium (Tl) concentrations in illicit opioid users along with the relevant clinical signs and symptoms consistent with thallotoxicosis and to compare them with the corresponding variables in the control non-opioid user group. MATERIALS AND METHODS: This case-control study was conducted on 50 illicit opioid users who had abused opioids continuously for more than a year, referred to Amirie Drug Abuse Treatment Clinic in Kashan, Iran. The control group included 50 non-opioid users. Thallium concentrations in urine, blood, and hair were assessed in both groups (n = 100) using electrothermal (graphite furnace) atomic absorption spectrometry (ET AAS, GF AAS). RESULTS: In the studied group, the median (interquartile range) concentrations of thallium in urine, blood, and hair were 54.8 ± 79.9 µg/L, 14.5 ± 11.1 µg/L, and 5.4 ± 3.7 µg/g, respectively; these values were 4.8 ± 5.2 µg/L, 2.5 ± 2.4 µg/L, and 1.4 ± 1.1 µg/g, respectively, in the control group. There were significant differences in urine, blood, and hair thallium concentrations between the study group and the control group (p < 0.001). There were significant correlations between duration of illicit opioid use and urine thallium concentrations (r = 0.394, p = 0.005) and hair thallium concentrations (r = 0.293, p = 0.039), but not with blood thallium concentrations (r = 0.246, p = 0.085). Urine and blood thallium concentrations of illicit opioid users with clinical signs and symptoms consistent with thallotoxicosis of weakness (p = 0.01), depression (p = 0.03), and headache (p = 0.03) were higher than users without these problems. DISCUSSION AND CONCLUSION: The results of the study showed that thallium concentrations in urine, blood, and hair in illicit opioid users were significantly higher than the comparable concentrations in the control group. This can be due to the use of illicit opioids adulterated with thallium. Also, this study showed long-term illicit opioid use may lead to thallium exposure. In addition, cigarette smoking was associated with increased thallium exposure.


Asunto(s)
Cabello/química , Trastornos Relacionados con Opioides , Talio , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos Opioides/toxicidad , Estudios de Casos y Controles , Femenino , Heroína/toxicidad , Humanos , Drogas Ilícitas/toxicidad , Irán/epidemiología , Masculino , Persona de Mediana Edad , Trastornos Relacionados con Opioides/sangre , Trastornos Relacionados con Opioides/epidemiología , Trastornos Relacionados con Opioides/metabolismo , Trastornos Relacionados con Opioides/orina , Opio/toxicidad , Talio/análisis , Talio/sangre , Talio/toxicidad , Talio/orina , Adulto Joven
7.
Forensic Sci Int ; 291: 230-233, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30227370

RESUMEN

In cases of criminal thallium poisoning, forensic investigation is required to identify the amount and time of thallium exposure. Usually, blood and urine thallium levels are respectively used as biomarkers. Additionally, hair has the unique potential to reveal retrospective information. Although several studies have attempted to clarify how thallium is distributed in hair after thallium poisoning, none have evaluated the time course of changing thallium distribution. We investigated changes in the distribution of thallium in hair at different time points after exposure in five criminal thallotoxicosis patients. Scalp hair samples were collected twice, at 2.6 and 4.2-4.5months after an exposure incident by police. Results of our segmented analysis, a considerable amount of thallium was detected in almost all hair sample segments. The thallium exposure date estimated from both hair sample collections matched the actual exposure date. We found that determination of thallium amounts in hair samples divided into consecutive segments provides valuable information about exposure period even if a considerable time passes after exposure. Moreover, when estimating the amount of thallium exposure from a scalp hair sample, it is necessary to pay sufficient attention to individual differences in its decrease from hair.


Asunto(s)
Cabello/química , Talio/análisis , Talio/envenenamiento , Adulto , Alopecia/inducido químicamente , Femenino , Toxicología Forense , Humanos , Japón , Masculino , Espectrometría de Masas/métodos , Persona de Mediana Edad , Parestesia/inducido químicamente , Té/química , Talio/farmacocinética , Adulto Joven
8.
Environ Monit Assess ; 189(2): 56, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28091884

RESUMEN

The risks to wildlife and humans from uranium (U) mining in the Grand Canyon watershed are largely unknown. In addition to U, other co-occurring ore constituents contribute to risks to biological receptors depending on their toxicological profiles. This study characterizes the pre-mining concentrations of total arsenic (As), cadmium (Cd), copper (Cu), lead (Pb), mercury (Hg), nickel (Ni), selenium (Se), thallium (Tl), U, and zinc (Zn); radiation levels; and histopathology in biota (vegetation, invertebrates, amphibians, birds, and mammals) at the Canyon Mine. Gross alpha levels were below the reporting limit (4 pCi/g) in all samples, and gross beta levels were indicative of background in vegetation (<10-17 pCi/g) and rodents (<10-43.5 pCi/g). Concentrations of U, Tl, Pb, Ni, Cu, and As in vegetation downwind from the mine were likely the result of aeolian transport. Chemical concentrations in rodents and terrestrial invertebrates indicate that surface disturbance during mine construction has not resulted in statistically significant spatial differences in fauna concentrations adjacent to the mine. Chemical concentrations in egg contents and nestlings of non-aquatic birds were less than method quantification limits or did not exceed toxicity thresholds. Bioaccumulation of As, Pb, Se, Tl, and U was evident in Western spadefoot (Spea multiplicata) tadpoles from the mine containment pond; concentrations of As (28.9-31.4 µg/g) and Se (5.81-7.20 µg/g) exceeded toxicity values and were significantly greater than in tadpoles from a nearby water source. Continued evaluation of As and Se in biota inhabiting and forging in the mine containment pond is warranted as mining progresses.


Asunto(s)
Minería , Monitoreo de Radiación , Oligoelementos/análisis , Uranio/análisis , Contaminantes Radiactivos del Agua/análisis , Animales , Arizona , Arsénico/análisis , Biota , Cadmio/análisis , Cobre , Humanos , Mercurio/análisis , Níquel , Exposición a la Radiación , Selenio , Talio/análisis , Zinc/análisis
9.
Nat Prod Commun ; 12(2): 167-170, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30428202

RESUMEN

Samples of Thymus alsarensis Ronniger, an endemic species for the Allchar locality, were evaluated for their polyphenolic composition and heavy metals. Allchar district is an abandoned antimony-arsenic-thallium deposit in the north-west of Kozuf Mountain, R. Macedonia, with a unique mineral composition affecting the mineral composition of the flora. A systematic method for phenolic compounds characterization was developed using mass spectrometry coupled to HPLC/DAD. Analyses were focused on the polyphenolic compounds to establish a possible correlation to the region specific heavy metals As and TI in the different organs of T. alsarensis. Twenty-seven polyphenols: phenolic acid derivatives and flavonoid glycosides of luteolin, apigenin, quercetin, and kaempferol were detected; contents were higher in the leaves and flowers compared with stems and roots. Quinic acid (1), prolithospermic acid (6), salvianolic acid B (7), salvianolic acid A (8), monomethyl lithospermate (9), luteolin dihexoside (12), luteolin pentosyl-hexoside (14), luteolin acetyl pentosyl-hexoside (16), luteolin acetyl hexoside (17), luteolin dipentoside (21), luteolin pentoside (24), luteolin acetyl dipentoside (25), kaempferol pentosyl-hexoside (19) and kaempferol acetyl pentosyl-hexoside (22) were detected in T. alsarensis for the first time. To assay the content of As and TI, root, stem, leaf and flower samples were analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES). Significant accumulation of As and TI was observed with As content from 0.25 to 140 mg/kg and TI from 0.10 to 496 mg/kg. The content of As was much higher in the roots, while the content of TI was significantly higher in the roots, flowers and leaves in all T. alsarensis specimens. Comparison of the results obtained for total polyphenols and for As and TI content does not suggest any correlation (positive or negative) between the total phenolic content and the content of TI and As. On the other hand, it is evident that the soil rich with specific heavy metals (TI and As) affects the type of polyphenolic compounds produced in different organs, compared with other Thymus species growing on soil that is not contaminated.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Metales Pesados/análisis , Fenoles/análisis , Talio/análisis , Thymus (Planta)/química , Arsénico/análisis , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Atómica
10.
Arh Hig Rada Toksikol ; 64(3): 385-94, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24084347

RESUMEN

Abstract Using inductively-coupled plasma mass spectrometry (ICP-MS), we measured the concentrations of thallium and uranium in local water resources from three villages (Celije, Draz, and Potnjani) in eastern Croatia, with the aim to determine if they were associated with the levels of these same elements in the serum, urine, and hair collected from the residents of this area. The exposure of the local population to thallium and uranium through drinking water was generally low. ICP-MS was capable of measuring the levels of both of the elements in almost all of the analysed samples. Although there were differences in the concentrations of both elements in water samples and biological specimens taken from the residents, they did not reach the maximum contaminant level in any of the four sample types studied. Although hair was previously reported as an excellent indicator of occupational and environmental exposure to various elements, our study did not confirm it as a reliable biological material for tracing thallium and uranium levels, mainly due to the very low concentrations of these elements, often well below the detection limit. However, our results have shown that the concentration of thallium and uranium in drinking water can be effectively traced in urine samples.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/estadística & datos numéricos , Talio/análisis , Uranio/análisis , Contaminantes Radiactivos del Agua/análisis , Abastecimiento de Agua/análisis , Adulto , Anciano , Croacia , Femenino , Cromatografía de Gases y Espectrometría de Masas , Cabello/química , Humanos , Masculino , Persona de Mediana Edad , Suero/química , Orina/química
11.
Georgian Med News ; (216): 60-4, 2013 Mar.
Artículo en Ruso | MEDLINE | ID: mdl-23567311

RESUMEN

UNLABELLED: Therapeutic muds or so called peloids belong to useful minerals. They contain therapeutic active substances (micro and macro elements, vitamins, bio stimulators etc.), animated bodies and they show expressed therapeutic effectiveness. At the first stage of the research the authors study the areas where peloids are spread and define their location in Ajara region. Therefore, the map is designed. The aim of the research at this stage is to define the composition of micro and macro elements in peloids spread in Kobuleti region. Research objects: therapeutic muds (peloids) discovered in Kobuleti region, particularly, in villages Kvirike and Chakhati. RESEARCH METHODS: the up-to-date physical-chemical analysis method using EDXRF spectrophotometer and program Epsilon 5 EDXRF was employed in order to define mineral composition in the found samples. On the basis of the exploration, it is ascertained that peloids gathered in Kobuleti region contain essence micro and macro elements as well as toxical elements in small quantities. The following potentially toxical elements as germanium, lithium, thallium, wolfram and tin do not manifest themselves in the raw materials. Based on the study of mineral composition in the muds taken for analysis, we can infer that their further study in different diseases is expedient. For instance, it shall be worthwhile in the cases of diverse cardiovascular system diseases (potassium, magnesium), for complex treatment and prophylaxis in the cases of joints diseases such as osteoporosis, rheumatism (calcium) and also for the correction of those pathologies that are caused by the lack of above mentioned elements in an organism. The high consistence of silicium and existence of sulphur in both peloids cause their further study for using in cosmetic practice.


Asunto(s)
Minerales/análisis , Peloterapia/métodos , Georgia (República) , Talio/análisis , Tungsteno/análisis
12.
Environ Sci Technol ; 46(20): 11086-94, 2012 Oct 16.
Artículo en Inglés | MEDLINE | ID: mdl-22992155

RESUMEN

Thallium (Tl) is emerging as a metal of concern in countries such as China due to its release during the natural weathering of Tl-bearing ore deposits and mining activities. Despite the high toxicity of Tl, few studies have examined the reductive dissolution of Tl mineral phases by microbial populations. In this study we examined the dissolution of synthetic Tl(I)-jarosite, (H(3)O)(0.29)Tl(0.71)Fe(2.74)(SO(4))(2)(OH)(5.22)(H(2)O)(0.78), by Shewanella putrefaciens CN32 using batch experiments under anaerobic circumneutral conditions. Fe(II) concentrations were measured over time and showed Fe(II) production (4.6 mM) in inoculated samples by 893 h not seen in mineral and dead cell controls. Release of aqueous Tl was enhanced in inoculated samples whereby maximum concentrations in inoculated and cell-free samples reached 3.2 and 2.1 mM, respectively, by termination of the experiment. Complementary batch Tl/S. putrefaciens sorption experiments were conducted under experimentally relevant pH (5 and 6.3) at a Tl concentration of 35 µM and did not show significant Tl accumulation by either live or dead cells. Therefore, in contrast to many metals such as Pb and Cd, S. putrefaciens does not represent a sink for Tl in the environment and Tl is readily released from Tl-jarosite during both abiotic and biotic dissolution.


Asunto(s)
Compuestos Férricos/metabolismo , Shewanella putrefaciens/metabolismo , Sulfatos/metabolismo , Talio/metabolismo , Contaminantes Químicos del Agua/química , Biodegradación Ambiental , China , Compuestos Férricos/análisis , Minería , Shewanella putrefaciens/fisiología , Sulfatos/análisis , Talio/análisis
13.
Sci Total Environ ; 421-422: 31-40, 2012 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-21440288

RESUMEN

Arsenic (As), selenium (Se) and thallium (Tl) are three trace metals (metalloids) of high concern in China because deficiency or excess expose can cause a range of endemic diseases, such as endemic arsenism, selenosis, Keshan disease (KD), Kashin-Beck disease (KBD) and thallotoxicosis. These specific endemic diseases were attributable for overabundance or deficiency (mainly referring to selenium) of these three elements in the local environment as a result of natural geochemical processes and/or anthropologic activities. The geochemistry and human health impacts of these three trace elements have been intensively studied since the 1970s in China, in terms of geochemical sources, distribution, transportation, health impact pathways, and prevention/remediation measures. Endemic arsenism in China are induced from the exposures of high As in either drinking water or domestic combustion of As-rich coals. Both endemic selenium deficiency and selenosis occurred in China. The KD and KBD were related to the deficiency of Se in the low-Se geological belt with Se contents in soil less than 0.125mg/kg stretching from northeast to southwest of China. Endemic selenosis occurred in areas with high Se concentrations in soils derived from the Se-enriched black carbonaceous siliceous rocks, carbonaceous shale and slate. Endemic Tl poisoning occurred in southwestern China due to Tl contamination in local drinking water and vegetables surrounding the Tl-rich sulfide mineralized areas. Some measures have been taken to control and remedy the endemic diseases with significant effects in reducing health risk and damage of As, Se and Tl. However, the states of the endemic diseases of As, Se and Tl in China are still serious in some areas, and substantial research efforts regarding the health impacts of these elements are further required. This paper reviews the progress of medical geology of As, Se and Tl in China, and provides with some outlooks for future research directions.


Asunto(s)
Arsénico/análisis , Contaminantes Ambientales/análisis , Selenio/análisis , Talio/análisis , Topografía Médica , Oligoelementos/análisis , Arsénico/toxicidad , China , Enfermedades Endémicas/prevención & control , Enfermedades Endémicas/estadística & datos numéricos , Monitoreo del Ambiente , Humanos , Selenio/deficiencia , Selenio/toxicidad , Talio/toxicidad
14.
Guang Pu Xue Yu Guang Pu Fen Xi ; 29(1): 256-8, 2009 Jan.
Artículo en Chino | MEDLINE | ID: mdl-19385252

RESUMEN

Fourteen Chinese traditional medicines were digested by microwave digestion, which are generally applied to treat tumor in clinic, and the contents of U, Th and Tl in the fourteen Chinese traditional medicines were determined by inductively coupled plasma mass spectrometry (ICP-MS), and the results show that the change ranges of the elements contents were: 0.005 153-0.1534 microg x g(-1) for U; 0.03501-0.4628 microg x g(-1) for Th; 0.00143-1.600 microg x g(-1) for Tl. The contents of U, Th and Tl in the fourteen Chinese traditional medicines were low, and not with one accord. The determination results of the fourteen Chinese traditional medicines were analyzed by SPSS 11.5, and the results show that there were not significant deviations(p>0.05) of the contents of U, Th and Tl between the medicine of treating the toxifying disease with poisonous agents and the medicines of heat-clearing. The study indicates that inductively coupled plasma mass spectrometry (ICP-MS) is a quick, accurate, sensitive method to determine the contents of U, Th and Tl in Chinese traditional medicine, and the results of this study provide reference data for using Chinese traditional medicine safely in clinic and developing Chinese traditional medicine.


Asunto(s)
Medicamentos Herbarios Chinos/química , Microondas , Análisis Espectral/métodos , Talio/análisis , Torio/análisis , Uranio/análisis , Análisis de Inyección de Flujo/métodos , Medicina Tradicional China
15.
Environ Pollut ; 157(3): 772-7, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19110352

RESUMEN

Subcellular selenium (Se) distributions in the oligochaete Tubifex tubifex and in the insect Chironomus riparius did not vary with Se exposure duration, which was consistent with the observations that the duration of prey Se exposure had little influence on either Se assimilation or loss by a predatory insect (the alderfly Sialis velata). However, these two prey types differed in how Se was distributed in their cells. Overall, the predator assimilated a mean of 66% of the Se present in its prey, which was similar to the mean percentage of Se in prey cells (62%) that was theoretically available for uptake (that is, Se in the protein and organelle fractions). Likewise, data for cadmium, nickel and thallium suggest that predictions of trace element transfer between prey and predator are facilitated by considering the subcellular partitioning of these contaminants in prey cells.


Asunto(s)
Chironomidae/metabolismo , Contaminantes Ambientales/metabolismo , Oligoquetos/metabolismo , Conducta Predatoria , Selenio/metabolismo , Animales , Cadmio/análisis , Cadmio/metabolismo , Ecología/métodos , Contaminantes Ambientales/análisis , Espacio Intracelular/química , Espacio Intracelular/metabolismo , Níquel/análisis , Níquel/metabolismo , Oligoquetos/química , Oligoquetos/ultraestructura , Selenio/análisis , Talio/análisis , Talio/metabolismo
16.
Health Phys ; 50(4): 509-13, 1986 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-3957672

RESUMEN

The aim of this research is the qualitative and quantitative determination by gamma-spectroscopy analysis of all the natural radioisotopes which exist in the waters of the municipal thermometallic radioactive springs (spas) of the Greek island Ikaria. An explanation is suggested for the different concentrations of natural radioisotopes in these spa waters in connection with physical factors (geological composition, temperature of the spas, etc.). In addition to the aforementioned, we also seek to compare radioactivity values of different spas during the same season as well as of an individual spa at different seasons of the year.


Asunto(s)
Balneología , Radioisótopos/análisis , Grecia , Radioisótopos de Potasio/análisis , Radio (Elemento)/análisis , Radón/análisis , Estaciones del Año , Temperatura , Talio/análisis , Agua/análisis
17.
Science ; 183(4121): 202-4, 1974 Jan 18.
Artículo en Inglés | MEDLINE | ID: mdl-4808856

RESUMEN

The toxic trace elements arsenic, antimony, cadmium, lead, selenium, and thallium were found to be most concentrated in the smallest respirable particles emitted from coal-fired power plants. These elements, or their compounds, are probably volatilized during combustion and preferentially adsorb or condense onto the small particles which can most easily pass through conventional control equipment.


Asunto(s)
Contaminación del Aire/análisis , Carbón Mineral/análisis , Residuos Industriales/análisis , Antimonio/análisis , Arsénico/análisis , Cadmio/análisis , Cromo/análisis , Plomo/análisis , Espectrometría de Masas , Níquel/análisis , Tamaño de la Partícula , Selenio/análisis , Espectrometría de Fluorescencia , Talio/análisis , Zinc/análisis
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