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1.
Water Sci Technol ; 81(6): 1273-1282, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32597413

RESUMO

N, S co-doped MnFe2O4@C magnetic nanoparticles were successfully synthesized by a simple method involving the preparation of MnFe2O4 nanoparticles and subsequent pyrolysis treatment. The physical and chemical properties of MnFe2O4, MnFe2O4@C and MnFe2O4@C-NS nanoparticles were characterized by X-ray diffraction (XRD), vibrating sample magnetometry (VSM), transmission electron microscopy (TEM), N2 adsorption-desorption and the pH at the point of zero charge. Their performances in the adsorption of Hg(II) from water were investigated. The adsorption process followed pseudo-second-order kinetics and the experimental data of equilibrium isotherms fitted well with the Langmuir model. MnFe2O4@C-NS showed the highest adsorption capacity of 108.56 mg/g, increasing more than 1.7 times compared to MnFe2O4. The enhanced adsorption performance was attributed to the larger specific surface area as well as the complexation of N and S ligands on the surface. The thermodynamic parameters of ΔH°, ΔS° and ΔG° at 30 °C were -24.39 kJ/mol, -0.046 kJ/mol K and -10.45 kJ/mol, respectively, which indicated that the adsorption of Hg(II) on MnFe2O4@C-NS was exothermic and spontaneous in nature. Moreover, MnFe2O4@C-NS showed superior selectivity towards Hg(II) compared with other metal ions generally present in mercury-containing industrial wastewater.


Assuntos
Nanopartículas de Magnetita , Mercúrio , Poluentes Químicos da Água , Purificação da Água , Adsorção , Concentração de Íons de Hidrogênio , Cinética , Termodinâmica
2.
J Environ Manage ; 269: 110858, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32561026

RESUMO

Litterfall constitutes one of the main vectors for mercury (Hg) transfer to forested ecosystems, so we studied the deposition of Hg through senescent vegetation (oak leaves, twigs and miscellaneous) in a deciduous forest plot of Southwest Europe dominated by Quercus robur in 2015 and 2016. Total Hg concentrations increased in the following order: bole wood (1.4 µg kg-1) < bark (8.3 µg kg-1) < twigs (12.2 µg kg-1) < miscellaneous (36.0 µg kg-1) < oak leaves (39.3 µg kg-1) < mineral soil (42.4 µg kg-1) < Oi horizons (48.7 µg kg-1) < Oe + Oa horizons (71.6 µg kg-1). Mercury accumulation rates in oak leaves during the growing season were 0.15-0.18 µg kg-1 day-1. Mercury deposition fluxes were 26 and 21 µg m-2 yr-1 for 2015 and 2016, respectively, with oak leaves being the fraction that contributed the most. Mercury determination in litterfall sorted biomass fractions lead to a more accurate estimation of the total annual Hg deposition fluxes through litterfall. Higher Hg content was obtained for organic horizons (average of 60.2 µg kg-1) than for mineral soil (mean of 42.4 µg kg-1), but the soil Hg pool was higher in the latter. The results confirmed the necessity of taking into account the Hg pool in the deeper mineral soil layers as they accumulate substantial quantities of Hg associated to organic C and Al compounds, preventing its mobilization to other compartments of the terrestrial ecosystems.


Assuntos
Mercúrio , Quercus , Poluentes do Solo , Ecossistema , Monitoramento Ambiental , Europa (Continente) , Florestas , Solo , Árvores
4.
Environ Monit Assess ; 192(6): 404, 2020 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-32472215

RESUMO

The St. Lawrence River, at Cornwall Ontario, has accumulated sediment contaminants, mainly mercury (Hg) and polychlorinated biphenyls (PCBs), from industrial point sources over many years. Although those sources are past, the river at Cornwall remains an Area of Concern (AOC). Because of remediation and other changes in the AOC, improved knowledge of contaminants in wild-fish and their putative links to health effects could help decision makers to better assess the AOC's state. Thus, we compared tissue concentrations of Hg, PCBs, morphometric measures of health, and biomarkers of exposure, metabolic-, and reproductive health in native brown bullhead (Ameiurus nebulosus) from the AOC to those of upstream reference fish. Linear discriminant analysis separated the adult fish of both sexes among upstream and downstream sites without misclassification. Burdens of total-Hg (all sites) and PCB toxic equivalents (downstream sites) exceeded the guidance for the protection of wildlife consumers. There were subtle effects of site on physiological variables, particularly in female fish. Total-Hg in tissue correlated negatively to plasma testosterone and 17ß-estradiol in female fish at Cornwall: moreover, concentrations of both hormones were lower within the AOC compared to reference site fish. A similar effect on vitellogenin, which was uncorrelated to E2/T at the downstream sites, indicated the potential for reproductive effects. Downstream fish also had altered thyroidal status (T3, TSH, and ratio of thyroid epithelial cell area to colloid area). Despite spatial and temporal variability of the endocrine-related responses, these subtle effects on fish health within the AOC warrant further study.


Assuntos
Ictaluridae , Mercúrio , Bifenilos Policlorados , Poluentes Químicos da Água , Animais , Monitoramento Ambiental , Feminino , Masculino , Ontário
5.
Water Res ; 179: 115895, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32450462

RESUMO

This study investigated the acute impact of heavy metals on activated sludge with respect to the amount properties of biopolymers and other solvable microbiological products (SMPs) released from the sludge. Ten heavy metals were selected for the evaluation. Under the experimental conditions, exposing activated sludge to different metals led to an increase in SMPs, with a more significant increase in nitrogenous organics than in carbonaceous ones, where Hg2+, Ag+, Cu2+, and Cr6+ led to the highest increase in SMP species, while Cd2+, Ni2+, Mn2+, Pb2+, and Co2+ caused limited increase in the middle and small SMP molecules, and Zn2+ and Cr3+ resulted in a decrease in SMP content. To probe the molecular impact of heavy metals and the association between cellular stress and SMP formation, the toxicity of heavy metals was evaluated using a toxicogenomics assay. Based on a correlation analysis between the increase in SMP and the molecular toxicity index-transcriptional effect level index (TELI) of different genes under corresponding stress conditions, eight genes demonstrated a strong correlation with SMP properties and were pre-assumed to have the most significant influence on the increment in SMPs. We further validated the correlation equation established to predict SMP production based on the molecular disturbance of the eight key biomarkers, using arsenic As3+ and vanadium V5+ as tests, and by quantifying the amount of SMPs released from the activated sludge under the influence of these metals using a TELI-derived equation. In addition, the heavy metals that generated greater amounts of reactive oxygen species also caused larger increases in SMPs.


Assuntos
Mercúrio , Metais Pesados , Esgotos , Águas Residuárias
6.
Sci Total Environ ; 732: 138983, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32417551

RESUMO

The Lower Amazon region (Western Pará, northern Brazil) is greatly affected by mining exploitations (particularly artisanal gold mines) and other industrial and intensive agricultural activities with potentially strong impacts on aquatic ecosystems. Although such impacts include contamination with various toxic elements, to date only the effects of Hg have been considered. In this study, toxic and trace element concentrations were determined in the flesh of 351 fish specimens, including detritivores (Acarí, Pterygoplichthys pardalis), omnivores (Piranha, Pygocentrus nattereri; Pirarucu, Arapaima sp.) and carnivores (Caparari, Pseudoplatystoma fasciatum; Tucunaré, Cichla ocellaris), during the dry and wet seasons in 2015 and 2016. The range of concentrations of toxic element residues were 2-238 µg/kg fresh weight for As, 1-77 µg/kg for Cd, 4-1922 µg/kg for Hg and 1-30 µg/kg for Pb. Only the maximum concentrations of Hg established in the Brazilian legislation for fish destined for human consumption (0.5 mg/kg) were exceeded (in 16% of carnivorous species). The large between-species and seasonal differences observed for all these toxic elements are probably related to the seasonal behaviour and dietary habits of the different fish species. By contrast, essential trace element concentrations were low and not related to seasonal or dietary factors, and the observed differences may be at least partly related to the metabolism of each species. The associations between Hg and the essential trace elements Se, Fe, Co and Mn deserve special attention, as these trace elements may play a role in Hg cycling and methylation and merit further evaluation with the aim of reducing Hg toxicity in aquatic environments.


Assuntos
Peixes , Animais , Brasil , Ecossistema , Monitoramento Ambiental , Mercúrio , Oligoelementos , Poluentes Químicos da Água
7.
Sci Total Environ ; 732: 139103, 2020 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-32428770

RESUMO

The Arctic marine ecosystem can be altered by processes of natural and anthropogenic origin. Spatio-temporal variation in species exposure to contamination is still poorly understood. Here, we studied elemental concentrations in the non-lethally collected samples from the most numerous seabird in European Arctic, the little auk (Alle alle) nesting in one breeding colony in Svalbard. This seabird spent the breeding season in the high-Arctic zone and the non-breeding period in sub-Arctic areas what may implicate spatio-temporal variation in elements bioaccumulation. We determined concentrations of 19 elements in adults feathers to determine levels of exposure during part of the pre-breeding (n = 74) and post-breeding (n = 74) seasons, feathers from nestlings (n = 18) to determine local contamination, and chick down (n = 16) and post-hatching eggshells (n = 18) to determine maternal input to offspring. During the pre-breeding period adults accumulated in their feathers significantly more Hg (one third of feathers exceeded the established toxicity threshold), Se and Mn compared to the post-breeding period. It reflects a higher exposition of birds to contaminants in pre-breeding moult areas outside the High Arctic compared to the post-breeding moult in the High Arctic. Sex differences in adult feathers representing the post-breeding period were found only for Ca and Zn with higher values in females. Chick down was characterized by high levels of several essential elements, an intermediate level of Hg and Se, and the highest Se:Hg molar ratios of all groups. Chick body feathers had the highest level of Cu and K among all the studied groups. Post-hatching eggshells were characterized by high Sr level (exceeding 2000 µg/g). Concentrations of several non-essential elements (Bi, Cd, Cr, Hg, Ni and Pb) in them were below method detection limits.


Assuntos
Ecossistema , Mercúrio , Animais , Regiões Árticas , Aves , Cruzamento , Monitoramento Ambiental , Plumas , Feminino , Masculino , Svalbard
8.
J Contemp Dent Pract ; 21(2): 129-132, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32381815

RESUMO

AIM: The aim of this study was to compare the level of mercury in the saliva of children with attention deficit/hyperactivity disorder (ADHD) as compared to age- and gender-matched controls in specific age groups. MATERIALS AND METHODS: A case-control observational study design was used. In school children with ADHD and outpatient dental clinics of a university dental hospital, the participants were schoolchildren diagnosed with ADHD studying in the first grade (6-7 years), sixth grade (12-13 years), and ninth grade (15-16 years) and were gender-matched to children without ADHD attending regular classes in school. Ninety children with ADHD comprised the test group while 90 children without ADHD comprised the control group. RESULTS: In this study, we found that children with ADHD had higher levels of salivary mercury than their age- and gender-matched counterparts; however, this difference was significant only in the 6-7 years of age group. The regression model showed a mild positive association between salivary mercury and ADHD; however, the association was not statistically significant. CONCLUSION: While there is some indication that salivary mercury may be higher in children with ADHD, there is insufficient evidence to establish a definite association between the two. CLINICAL SIGNIFICANCE: The study highlights the need to evaluate existing evidence on the role of mercury, especially salivary mercury, in ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Mercúrio , Estudos de Casos e Controles , Criança , Humanos , Saliva
9.
Cent Eur J Public Health ; 28(1): 40-43, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32228815

RESUMO

OBJECTIVE: Mercury dental amalgam restorations are an important source of chronic exposure to mercury in the whole population and special attention should be paid not only to occupational exposure to mercury during the preparation and administration of amalgam. The authors' report is an up-to-date contribution to the health risk assessment of mercury use in dentistry, namely occupational exposure to mercury in dentists working with dental amalgam and exposure to mercury in persons treated with amalgam dental restorations. METHODS: Determination of total mercury in samples of biological material (urine, hair) was performed during 2017 and 2018 in 50 persons by the AAS method using the mercury vapour generation technique at 254.6 nm. RESULTS: Current dental exposures based on the most recent findings do not exceed acceptable risk levels and are below the biological limit of mercury in urine valid for occupationally exposed persons (100 µg.g-1 of creatinine), namely median value was 1.48 (min. < limit of detection (LOD), max. 17.14) µg.g-1 of creatinine (40 persons), total mercury content in hair of dental personnel expressed as median value was 0.340 (min. 0.060, max.1.628) µg.g-1. In controls (10 persons) was total mercury content in urine expressed as median value 0.36 (min. < LOD, max. 2.74) µg.g-1 of creatinine, in hair was median value 0.224 (min. 0.059, max. 0.453) µg.g-1. CONCLUSIONS: Authors support opinion that amalgam fillings in the oral cavity are a permanent source of mercury for the body itself.


Assuntos
Amálgama Dentário/efeitos adversos , Exposição Ambiental/efeitos adversos , Mercúrio/efeitos adversos , Mercúrio/análise , Exposição Ocupacional/efeitos adversos , Exposição Ambiental/análise , Cabelo/química , Humanos , Mercúrio/urina , Exposição Ocupacional/análise , Medição de Risco
10.
Ecotoxicology ; 29(4): 485-492, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32297060

RESUMO

Experiments examining mercury (Hg) toxicity in Daphnia are usually conducted in highly standardized conditions that prevent the formation of biofilm. Although such standardization has many advantages, extrapolation of results to natural conditions and inference of ecological effects is challenging. This is especially true since biofilms can accumulate metals/metalloids and play a key role in their transfer to higher trophic level organisms. In this study, we experimentally tested the effects of spontaneously appearing biofilm in Daphnia cultures on accumulation of Hg and its natural antagonist selenium (Se) in Daphnia magna. We added Hg (in the form of mercury (II) chloride) at two concentrations (0.2 µg/L and 2 µg/L) to experimental microcosms and measured the uptake of Hg and Se by D. magna in the presence and absence of biofilm. To test for consistent and replicable results, we ran two identical experimental sets one week apart. Biofilm presence significantly reduced the accumulation of Hg, while increasing the tissue Se content in D. magna, and these findings were reproducible across experimental sets. These findings indicate that highly standardized tests may not be adequate to predict the bioaccumulation and potential toxicity of metals/metalloids under natural conditions.


Assuntos
Biofilmes/efeitos dos fármacos , Daphnia/metabolismo , Mercúrio/metabolismo , Selênio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Biofilmes/crescimento & desenvolvimento
12.
Waste Manag ; 107: 276-284, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32320940

RESUMO

Co-pyrolysis is a promising approach to recover energy from sewage sludge (SS) and municipal solid waste (MSW). Hg emission during this process has serious environmental risks. To reduce the environmental impact, orthogonal experiments on the blending ratio, heating rate, pyrolysis temperature, and residence time were conducted during SS and MSW co-pyrolysis. Variance analysis was used to determine the influence and synergetic effects of these factors. Multivariate nonlinear, neural network, random forest, and support vector machine models were used to simulate the Hg distribution based on four parameters, which were later optimized to optimize the Hg fixing ratio in pyrolysis char. The Hg was mainly distributed in the pyrolysis gas and char. The variance analysis results indicate that the blending ratio is the key factor influencing Hg distribution, and there is little synergetic effect among the four factors. Further experiments showed that a blending ratio of 87.5 SS wt% could enhance Hg fixation in char. The neural network model shows the best simulation performance with a mean relative error of 8.92%. The optimal parameters are a heating rate of 7 °C/min, pyrolysis temperature of 300 °C, and residence time of 10 min, resulting in a Hg fixing ratio of 25.68 wt% in pyrolysis char. The simulated Hg fixation characteristics correlate with the experimental results. This study provides insights into Hg distribution under various conditions during co-pyrolysis of SS and MSW. It is hoped that this work can contribute to the control of Hg during the waste treatment and utilization process.


Assuntos
Mercúrio , Resíduos Sólidos , Pirólise , Esgotos , Temperatura
13.
Bull Environ Contam Toxicol ; 104(5): 595-601, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32242255

RESUMO

Total mercury (THg) and selenium (TSe) levels were measured in stomach contents (SC) and twelve tissues of cutthroat trout (Oncorhynchus clarkii) occurring in three high-elevation lakes of Colorado, USA, inhabiting watersheds absent past and current mining activities. For 32 of 36 tissues, including muscle, mean THg wet weight (ww) concentrations were greater than in the diet (SC) for all sites, indicating biomagnification. Ranges of THg (µg/kg ww) for SC and stomach tissue (ST) were 1.23-73.54 and 14.55-61.35, respectively. Selenium concentrations in fish muscle were not greater than in the SC indicating a trophic transfer factor < 1.0. However, in several other tissues, mean Se dry weight (dw) levels were greater than in SC for all three lakes. Ranges of TSe for SC and ST were 166-7544 and 797-7523 (µg/kg dw), respectively. The muscle to egg/ovary ratio for Se averaged 2.30, 4.60, and 2.68 for the three populations. The variability of SC (planktonic vs. benthic) and differential distributions of THg and TSe in SC and organ-tissues generated questions focusing on the seasonal, physiological, and genetic drivers of these organometal(loid)s in subalpine trout.


Assuntos
Bioacumulação , Monitoramento Ambiental/métodos , Conteúdo Gastrointestinal/química , Mercúrio/metabolismo , Oncorhynchus/metabolismo , Selênio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Colorado , Cadeia Alimentar , Lagos/química , Mercúrio/análise , Mineração , Plâncton/química , Selênio/análise , Poluentes Químicos da Água/análise
14.
Ecotoxicology ; 29(4): 459-484, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32239332

RESUMO

Chemical contaminants are a threat to the Chesapeake Bay watershed, with mercury (Hg) among the most prevalent causes of impairment. Despite this, large-scale patterns of Hg concentrations, and the potential risks to fish, wildlife, and humans across the watershed, are poorly understood. We compiled fish Hg data from state monitoring programs and recent research efforts to address this knowledge gap and provide a comprehensive assessment of fish Hg concentrations in the watershed's freshwater habitats. The resulting dataset consisted of nearly 8000 total Hg (THg) concentrations from 600 locations. Across the watershed, fish THg concentrations spanned a 44-fold range, with mean concentrations varying by 2.6- and 8.8-fold among major sub-watersheds and individual 8-digit hydrological units, respectively. Although, mean THg concentrations tended to be moderate, fish frequently exceeded benchmarks for potential adverse health effects, with 45, 48, and 36% of all samples exceeding benchmarks for human, avian piscivore, and fish risk, respectively. Importantly, the percentage of fish exceeding these benchmarks was not uniform among species or locations. The variation in fish THg concentrations among species and sites highlights the roles of waterbody, landscape, and ecological processes in shaping broad patterns in Hg risk across the watershed. We outline an integrated Hg monitoring program that could identify key factors influencing Hg concentrations across the watershed and facilitate the implementation of management strategies to mitigate the risks posed by Hg.


Assuntos
Monitoramento Ambiental , Peixes/metabolismo , Mercúrio/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Baías , Ecossistema , Compostos de Metilmercúrio
15.
Environ Monit Assess ; 192(5): 286, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32297009

RESUMO

Several trace metals and metalloids have been introduced into aquatic ecosystems due to anthropogenic activities. Some of these elements like mercury (in the form of methylmercury) are easily transferred from one trophic level to another and can accumulate to toxic quantities in organisms at the top of aquatic food webs. For this reason, seabirds like the eastern brown pelican (Pelecanus occidentalis carolinensis) are susceptible to heavy metal and metalloid toxicity and may warrant periodic monitoring. Mercury, cadmium, copper, arsenic, and selenium were measured in the feathers of adult brown pelicans and chicks in several breeding colonies (Shamrock Island, Chester Island, Marker 52 Island, North Deer Island, Raccoon Island, Felicity Island, Gaillard Island, Audubon Island, and Ten Palms Island) in the northern Gulf of Mexico. Overall, most chicks and adults examined had mercury levels in feathers that were below the concentration range in which birds show symptoms of mercury toxicity. However, chicks in the Audubon Island and Ten Palms Island colonies displayed mercury levels that were 3 times higher than values observed in 5 other colonies. In addition, several adults and chicks displayed selenium concentrations that are above what is considered safe for birds. Cadmium quantities in feathers were below levels that trigger toxicity in birds. Similarly, arsenic measurements were at quantities below the average of what has been reported for birds living in contaminated sites. Finally, we identify pelican breeding colonies that may warrant monitoring due to elevated levels of contaminants.


Assuntos
Aves , Monitoramento Ambiental , Metais/análise , Animais , Arsênico , Cruzamento , Cádmio , Cobre , Ecossistema , Plumas , Golfo do México , Mercúrio , Selênio
16.
Environ Monit Assess ; 192(5): 279, 2020 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-32279131

RESUMO

Correlation between metal concentrations in fish tissues and fish body size poses certain challenge when comparing concentration levels encountered at different locations or time periods by degrading performance of statistical tests due to variable age composition of fish sample pool. In order to overcome this, the concentrations of Hg, Cu, and Zn, measured in tissues of five fish species, were normalized to selected age group. Computed species-specific equations, based on empirically obtained exponential relationship, provided accurate estimates of the normalized concentrations under the conditions of substantial metal and fish age covariation. Obtained normalized and measured concentrations were then compared among sampling stations by means of commonly used analysis of variance (ANOVA) in combination with Tuckey's HSD test, where 11 out of 18 considered cases showed significant smoothing of the observed differences. The applied method worked well in the case of locally distributed coastal species populations where transformed data allowed clearer separation of spatial areas exhibiting different levels of pollution. At the same time, application of the method on pelagic fish species was less successful due to high mobility of specimens and mixed impact on the population originating from variable pollution levels at different areas of the entire migration region; therefore, attribution of a sample pool to a specific catchment area can cause a bias in assessment results.


Assuntos
Monitoramento Ambiental , Metais/metabolismo , Músculos/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Cobre , Ecossistema , Peixes/metabolismo , Mercúrio , Zinco
17.
Environ Monit Assess ; 192(5): 290, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-32300920

RESUMO

With the rapid advancement of industrialization without effective supervision, industrial aquatic toxic metal (TM) emissions pose threats to human health in China. Due to differences in socioeconomic development, the regional disparity of industrial aquatic TM emissions is obvious nationwide. In this study, the human health impacts (HHIs) of industrial aquatic TM emissions (i.e., mercury (Hg), cadmium (Cd), hexavalent chromium (Cr(VI)), lead (Pb), and arsenic (As)) in the 31 provinces of China were evaluated based on the ReCiPe method, and the driving factors affecting HHIs from 2000 to 2015 were decomposed using the logarithmic mean Divisia index (LMDI) method. The results showed that the HHIs gradually decreased, with more than an 80% decrease from 2000 to 2015. The order of the TMs contributing to the national HHIs in 2015 was as follows: As (79.5%) > Cr(VI) (19.6%) > Hg (0.4%) > Pb (0.2%) = Cd (0.2%), and 21 (68%) provinces were dominated by industrial aquatic As emissions. Economic development is the major driving factor of the increase in HHIs, while the HHI strength and wastewater discharge intensity are the key driving factors causing reductions in the HHIs. Hunan, Inner Mongolia, Hubei, and Jiangxi accounted for approximately 55% of the total HHIs in 2015. Some suggestions for reducing HHIs based on the local realities of different provinces were put proposed considering two aspects: economic strategy and technical capability.


Assuntos
Mercúrio , Metais Pesados , Poluentes da Água , China , Saúde Ambiental , Monitoramento Ambiental , Intoxicação por Metais Pesados , Humanos , Indústrias , Poluentes da Água/toxicidade
18.
Chemosphere ; 253: 126685, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32289605

RESUMO

Shellfishes can easily accumulate metals via water and sediment and which may pose a human health risk by consumption. This study assessed the distribution of metals, including Cd, Cr, Cu, Pb, Ni, Zn, and Hg, in soft tissues of hard clam (Meretrix lusoria), surrounding water body, and sediment in the southwest coast of Taiwan. Hard clams contained the relatively higher concentration of the essential element, such as Zn, Cu, and Ni, and the metal concentration from high to low was Zn > Cu > Ni > Cd > Cr > Pb > Hg. However, the metal concentrations found in hard clam all were lower than the Sanitation Standard for Aquatic Animal of Taiwan. Results of bioaccumulation factors indicated that hard clam shows the ability of metal accumulation from water was higher than that from sediment. Moreover, the metal concentrations in hard clam were negatively correlated with body size except for Hg, which could be presented by the significant power function. Generally, hard clams from the aquaculture pond located on the southwest coast of Taiwan would not be harmful to adult consumers, except for people that consume shellfish more than 100 g. Besides strengthening the management of seafood safety and aquaculture, adjusting the eating and purchasing habits of the consumer could be a practical and feasible way for decreasing health risks. These results can assist the government in determining seafood safety and its implementation in Taiwan.


Assuntos
Aquicultura , Exposição Dietética/estatística & dados numéricos , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Animais , Bioacumulação , Biometria , Bivalves , Sedimentos Geológicos , Humanos , Mercúrio , Metais/análise , Metais Pesados/análise , Tanques , Alimentos Marinhos/análise , Frutos do Mar , Taiwan
19.
Zhongguo Zhong Yao Za Zhi ; 45(2): 352-360, 2020 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-32237318

RESUMO

In this paper, some quality problems of mineral medicine Calamina and calcined Calamina have been discussed after determination and analysis of the quality parameters of a large number of market samples, and the countermeasures are put forward. According to the XRD results, as well as the results of tests included in Chinese Pharmacopoeia(2015 edition), the authenticity of Calamina and calcined Calamina samples were identified. The content of zinc oxide in samples were determined by the method of determination in Chinese Pharmacopoeia. Individually, inductively coupled plasma mass spectrometry(ICP-MS), inductively coupled plasma atomic emission spectrometry(ICP-AES) and atomic fluorescence spectrometry(AFS) methods were used for the determination of impurity elements and harmful elements in Calamina and calcined Calamina samples. Four kinds of impurity elements of magnesium(Mg), iron(Fe), aluminum(Al), calcium(Ca) and five harmful elements such as lead(Pb), cadmium(Cd), arsenic(As), copper(Cu), mercury(Hg) were measured. The study showed that: ① Fake Calamina products on the market were overflowing; ② The mineral origin of the mainstream Calamina in the market is inconsistent with that stipulated in Chinese Pharmacopoeia(2015 edition); ③ The contents of harmful elements Pb and Cd in Calamina and calcined Calamina are generally higher, while the contents of harmful elements As and Cu in some inferior Calaminae are higher; ④ Parts of calcined Calamina were improperly or inadequately processed. In view of these quality problems, the countermeasures are put forward as follows: ① It is suggested that hydrozincite should be approved as the mineral source of Calamina, and be included by Chinese Pharmacopoeia; ② Strengthen the research on the specificity of Calamina identification methods to improve the quality control level; ③ Strengthen the research on the processing of Calamina, and formulate the limit standards for the content of Pb and Cd in Calamina; ④ Carry out research on the artificial synthesis of Calamina and calcined Calamina, in order to cope with the current shortage of Calamina resources and ensure the sustainable development of Calamina medicinal materials.


Assuntos
Medicamentos de Ervas Chinesas/química , Compostos Férricos/química , Controle de Qualidade , Óxido de Zinco/química , Arsênico , Cádmio , Cobre , Combinação de Medicamentos , Medicamentos de Ervas Chinesas/normas , Compostos Férricos/normas , Ferro , Chumbo , Medicina Tradicional Chinesa , Mercúrio , Minerais , Oligoelementos/análise , Óxido de Zinco/normas
20.
Chemosphere ; 252: 126562, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32224360

RESUMO

The present study tested whether the presence of potentially toxic elements (PTEs) (Cd, Cr, Cu, Pb, Hg and Ni), commonly found in wastewaters, interferes with the ability of macroalgae (Ulva intestinalis, Ulva lactuca, Fucus spiralis, Fucus vesiculosus, Gracilaria sp. and Osmundea pinnatifida) to remove rare earth elements (REEs) (La, Ce, Pr, Nd, Eu, Gd, Tb, Dy and Y), which are key elements for most high technologies (e.g. electronics, aerospace, renewable energy). Results proved the high capacity of living macroalgae to remove REEs from multielement solutions, with the following sequence of bioconcentration factors being observed: U. intestinalis (2790) > Gracilaria sp. (2119) > O. pinnatifida (1742) > U. lactuca (1548) > F. vesiculosus (944) > F. spiralis (841). Competition among REEs to sorption sites on the six macroalgae was minor due to the chemical similarities between the elements. However, Ce and Y were the less removed while Gd, La and Eu the most removed among REEs. Ionic strength was an important factor in the sorption process, with salinity affecting differently the six macroalgae. Surprisingly, the presence of potential toxic elements in solution enhanced the removal of REEs. The most plausible explanation is the preferentially complexation of those elements by carbonates over REEs, which facilitates the binding of REEs cations onto the surface of macroalgae.


Assuntos
Metais Terras Raras/metabolismo , Alga Marinha/metabolismo , Poluentes Químicos da Água/metabolismo , Fucus , Mercúrio/metabolismo , Salinidade , Ulva , Poluição da Água
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