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The impact of military activities on the concentration of mercury in soils of military training grounds and marine sediments Полный текст
2016
Gębka, Karolina | Bełdowski, Jacek | Bełdowska, Magdalena
Military activities have been conducted on land and at sea. Both during conflicts and in peace time, some regions served as a military training ground which included firing positions and bunkers. Mercury fulminate has been used in ammunition primers and detonators. Certain amount of ammunition was dumped into the Baltic Sea after the Second World War. Because of corroded containers, mercury can be released into the marine environment. The soil and sediment samples were taken from military training grounds, southern Baltic in 2014 and 2015. The concentration of mercury was determined by AMA-254 analyzer. Hg concentration was higher in the places of military activities, as compared to other areas. Ten times increased concentration of Hg was determined in soil sample collected in area of active gun range compared to the reference station. The significant higher concentration of mercury was detected in stations where chemical warfare agents were found.
Показать больше [+] Меньше [-]Macroinvertebrate assemblages in agricultural, mining, and urban tropical streams: implications for conservation and management Полный текст
2016
Mwedzi, Tongayi | Bere, Taurai | Mangadze, Tinotenda
The study evaluated the response of macroinvertebrate assemblages to changes in water quality in different land-use settings in Manyame catchment, Zimbabwe. Four land-use categories were identified: forested commercial farming, communal farming, Great Dyke mining (GDM) and urban areas. Macroinvertebrate community structure and physicochemical variables data were collected in two seasons from 41 sites following standard methods. Although not environmentally threatening, urban and GDM areas were characterised by higher conductivity, total dissolved solids, salinity, magnesium and hardness. Chlorides, total phosphates, total nitrogen, calcium, potassium and sodium were significantly highest in urban sites whilst dissolved oxygen (DO) was significantly higher in the forested commercial faming and GDM sites. Macroinvertebrate communities followed the observed changes in water quality. Macroinvertebrates in urban sites indicated severe pollution (e.g. Chironomidae) whilst those in forested commercial farming sites and GDM sites indicated relatively clean water (e.g. Notonemouridae). Forested watersheds together with good farm management practices are important in mitigating impacts of urbanisation and agriculture. Strategies that reduce oxygen-depleting substances must be devised to protect the health of Zimbabwean streams. The study affirms the wider applicability of the South African Scoring System in different land uses.
Показать больше [+] Меньше [-]Evaluating the dynamical characteristics of particle matter emissions in an open ore yard with industrial operation activities Полный текст
2016
Cong, X. C. | Yang, G. S. | Qu, J. H. | Dai, M. X.
A study to investigate the dynamical characteristics of particle matter emissions in a working open yard is conducted in Caofeidian Port of Hebei Province, China. The average diurnal concentrations of the total suspended particulate (TSP) matter and respirable particulate matter (PM₁₀ and PM₅) are monitored during the field measurement campaign. Sampling is performed at a regular interval at 8 monitoring stations in the yard with normal industrial activities. The average TSP, PM₁₀ and PM₅ concentrations range from 285 to 568, 198 to 423 and 189 to 330 μg.m-3 in the yard, respectively. The linear regression correlation coefficient of TSP/PM₁₀ and TSP/PM₅ is 0.95±0.01 and 0.88±0.02, respectively.By using the Spearman correlation method, the wind speed and relative humidity are both weakly correlated with the PM₁₀ and PM₅ concentrations according to the measurements. In addition, industrial operation activities, such as vehicular traffic in the yard and the loading time of stackers, are significantly positively correlated with the PM concentration. Using the multivariate regression method, the main parameters influencing the TSP concentration variations are integratedly analysed. The traffic volume is found to be a significant predictor of TSP concentration variation, with the smallest P value (P<0.05).To understand the dynamical characteristics of particle emissions in the yard, the emissions from the truck transports, that is, from unpaved haul roads and from the loading process, are established. Then, the dynamical emission factor (EFD) based on the industrial activities in the yard is proposed. The dynamical emissions average 5.25x10⁵ kg.year⁻¹ and EFD is evaluated to be 0.29 kg.(ton.day)⁻¹ during the measurement period. These outcomes have meaningful implications not only for understanding the dynamical characteristics of particle emissions in the working stockyard but also for implementing effective control measures at appropriate sites in the harbour area.
Показать больше [+] Меньше [-]Degradation of benzophenone-3 by the ozonation in aqueous solution: kinetics, intermediates and toxicity Полный текст
2016
Guo, Yang | Lin, Qiaoxin | Xu, Bingbing | Qi, Fei
Benzophenone-3 (BP-3) is a popular ultraviolet absorbing chemical and has an adverse impact on aquatic ecosystems and human health. We determined the reaction kinetic constants of BP-3 and its de-proton pattern reacting with the molecular ozone or hydroxyl radical (·OH) for the first time. The obtained constant of the molecular ozone reacting with BP-3 or BP-3⁻ was 1.03(±0.21) × 10² or 1.85(±0.098) × 10⁵ M⁻¹ s⁻¹, respectively. And, the constant for BP-3 reacting with ·OH was 9.74(±0.21) × 10⁹ or 10.13(±0.25) × 10⁹ M⁻¹ s⁻¹ as using 4-chlorobenzoic acid and benzotriazole as reference compounds, respectively. The intermediates generated in the molecular ozone (12 kinds) or ·OH oxidation (18 kinds) were identified by LC-MS/MS. The removal efficiency of BP-3 in ozonation was dependent on the initial concentration of ozone, BP-3, and matrix water quality. The detoxification of BP-3 ozonation was depended on initial ozone dose using Chlorella vulgaris as the probe. Higher ozone dose increased the toxicity of the solution for more BP-3 being degraded and more intermediates formed, suggesting that the sole ozonation is not an effect approach for the degradation of BP-3 and some other energy should be combined.
Показать больше [+] Меньше [-]Content of metals and metabolites in honey originated from the vicinity of industrial town Košice (eastern Slovakia) Полный текст
2016
Kováčik, Jozef | Grúz, Jiří | Biba, Ondřej | Hedbavny, Josef
Composition of three types of honey (mixed forest honey and monofloral—black locust and rapeseed honeys) originated from the vicinity of an industrial town (Košice, Slovak Republic) was compared. Higher content of minerals including toxic metals in forest honey (1358.6 ng Ni/g, 85.6 ng Pb/g, and 52.4 ng Cd/g) than in rapeseed and black locust honeys confirmed that botanical origin rather than the distance for eventual source of pollution (steel factory) affects metal deposition. Benzoic acid derivatives were typically more accumulated in forest but cinnamic acid derivatives and some flavonoids in rapeseed honey (in free and/or glycoside-bound fraction). In terms of quantity, p-hydroxybenzoic and p-coumaric acids were mainly abundant. Total phenols, thiols, and proteins were abundant in forest honey. Some metals and phenols contributed to separation of honeys based on principal component analysis (PCA). Native amount of 5-(hydroxymethyl)furfural was not related to honey type (~11 μg/g) and was elevated after strong acid hydrolysis (200–350 μg/g) but it did not interfere with the assay of phenols by Folin-Ciocalteu reagent. This is the first report of metals and metabolites in the same study, and data are discussed with available literature. We conclude that black locust (acacia) honey is the most suitable for daily use and that central European monofloral honeys contain lower amounts of toxic metals in comparison with other geographical regions.
Показать больше [+] Меньше [-]Spatial monitoring of heavy metals in the inland waters of Serbia: a multispecies approach based on commercial fish Полный текст
2016
Milošković, Aleksandra | Dojčinović, Biljana | Kovačević, Simona | Radojković, Nataša | Radenković, Milena | Milošević, Djuradj | Simić, Vladica
The study monitored the contamination of fish muscle tissue by elements Al, As, Cd, Co, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn at 17 sampling sites, in order to assess the pollution status of the main rivers in Serbia. Of the six commercially important fish species included in the study (pikeperch Sander lucioperca, catfish Silurus glanis, bream Abramis brama, barbel Barbus barbus, chub Squalius cephalus, nase Chondrostoma nasus), the bioconcentration factor (BCF) indicated that benthivore bream and barbel and predatory catfish have the highest tendency toward the accumulation of elements. This study achieved its primary objective and produced a contamination map of Serbia as a basis for further research. The estimated metal pollution index (MPI) showed the Tisa River to be unaffected by direct pollution (with an MPI value of 0.31) and the West Morava and Pek rivers to be affected (with MPI values of 1.92 and 0.73 for the WM₁ and WM₂ sampling sites and 0.65 for the Pek sampling site). Over the past two decades, Serbia has not expanded its industrial activity, which has resulted in the barely noticeable anthropogenic input of heavy metals in the rivers close to industry, and the main rivers are mostly unaffected and slightly affected. We assumed that pollution by heavy metals in the 1990s was trapped in the sediment, thus showing an increased concentration of elements in the species that live and feed on the bottom. Hg concentrations exceeded the maximum permitted concentrations (MPCs) only in catfish samples (0.62 mg kg⁻¹) from the Danube (D₃ sampling site) and barbel (0.78 mg kg⁻¹) from the West Morava (WM₁ sampling site), while Cd concentrations exceeded the MPC in catfish samples (0.09 mg kg⁻¹) from the Danube (D₁ sampling site) and chub samples (0.1 mg kg⁻¹) from the South Morava (SM₂ sampling site). The average concentrations of Pb exceeded the MPC in chub and barbel samples (0.32 and 0.82 mg kg⁻¹, respectively) from the West Morava (WM₁ sampling site); chub, barbel, and nase samples (0.35, 0.32, 0.31 mg kg⁻¹, respectively) from the West Morava (WM₂ sampling site); chub and barbel samples (0.35 and 0.3 mg kg⁻¹, respectively) from the Ibar; chub samples (0.39 mg kg⁻¹) from the Drina; chub and barbel samples (0.59 and 0.4 mg kg⁻¹, respectively) from the Great Timok; and nase samples (0.33 mg kg⁻¹) from the Pek. These results demonstrate that there is a need for future studies that would involve similar analyses and focus especially on smaller rivers that have been neglected so far.
Показать больше [+] Меньше [-]Accumulation and distribution of mercury in fruiting bodies by fungus Suillus luteus foraged in Poland, Belarus and Sweden Полный текст
2016
Saba, Martyna | Falandysz, Jerzy | Nnorom, Innocent C.
Presented in this paper is result of the study of the bioconcentration potential of mercury (Hg) by Suillus luteus mushroom collected from regions within Central, Eastern, and Northern regions of Europe. As determined by cold-vapor atomic absorption spectroscopy, the Hg content varied from 0.13 ± 0.05 to 0.33 ± 0.13 mg kg⁻¹ dry matter for caps and from 0.038 ± 0.014 to 0.095 ± 0.038 mg kg⁻¹ dry matter in stems. The Hg content of the soil substratum (0–10 cm layer) underneath the fruiting bodies showed generally low Hg concentrations that varied widely ranging from 0.0030 to 0.15 mg kg⁻¹ dry matter with mean values varying from 0.0078 ± 0.0035 to 0.053 ± 0.025 mg kg⁻¹ dry matter, which is below typical content in the Earth crust. The caps were observed to be on the richer in Hg than the stems at ratio between 1.8 ± 0.4 and 5.3 ± 2.6. The S. luteus mushroom showed moderate ability to accumulate Hg with bioconcentration factor (BCF) values ranging from 3.6 ± 1.3 to 42 ± 18. The consumption of fresh S. luteus mushroom in quantities up to 300 g week⁻¹ (assuming no Hg ingestion from other foods) from background areas in the Central, Eastern, and Northern part of Europe will not result in the intake of Hg exceeds the provisional weekly tolerance limit (PTWI) of 0.004 mg kg⁻¹ body mass.
Показать больше [+] Меньше [-]Evaluating the ameliorative efficacy of Spirulina platensis on spermatogenesis and steroidogenesis in cadmium-intoxicated rats Полный текст
2016
Farag, Mayada R. | Abd EL-Aziz, R. M. | Ali, H. A. | Ahmed, Sahar A.
The present study was conducted to evaluate the ameliorative efficacy of Spirulina platensis (SP) on reproductive dysfunctions induced by cadmium chloride (CdCl₂) in male rats. Rats (n = 40) were divided into five groups (eight rats/each). Group 1: served as control without any treatment. Group 2: Rats were administered SP (150 mg/kg body weight (BW)) in drinking water for 10 days. Group3: Rats were subcutaneously injected with CdCl₂ (2 mg/kg BW) daily for 10 days. Group 4: Rats were co-treated with both CdCl₂ (2 mg/kg BW) and SP (150 mg/kg BW) daily for 10 days (SP prophylactic group). Group5: Rats received CdCl₂ for 10 days followed by administration of SP alone in drinking water daily for another 30 days with the same mentioned routes and doses (SP treatment group). From our findings, the administration of SP alone or co-administration with Cd significantly attenuated the harmful effects of Cd, suggesting its beneficial role in improving spermatogenesis and steroidogenesis after Cd exposure.
Показать больше [+] Меньше [-]Biomonitoring of agricultural workers exposed to pesticide mixtures in Guerrero state, Mexico, with comet assay and micronucleus test Полный текст
2016
Carbajal-López, Yolanda | Gómez-Arroyo, Sandra | Villalobos Pietrini, Rafael | Calderón-Segura, María Elena | Martínez Arroyo, Amparo
The aim of this study was to evaluate the genotoxic effect of pesticides in exfoliated buccal cells of workers occupationally exposed in Guerrero, Mexico, using the comet assay and the micronucleus test. The study compared 111 agricultural workers in three rural communities (Arcelia 62, Ajuchitlan 13, and Tlapehuala 36), with 60 non-exposed individuals. All the participants were males. The presence of DNA damage was investigated in the exfoliated buccal cells of study participants with the comet assay and the micronucleus (MN) test; comet tail length was evaluated in 100 nuclei and 3000 epithelial cells of each individual, respectively; other nuclear anomalies such as nuclear buds, karyolysis, karyorrhexis, and binucleate cells were also evaluated. Study results revealed that the tail migration of DNA and the frequency of MN increased significantly in the exposed group, which also showed nuclear anomalies associated with cytotoxic or genotoxic effect. No positive correlation was noted between exposure time and tail length and micronuclei frequencies. No significant effect on genetic damage was observed as a result of age, smoking, and alcohol consumption. The MN and comet assay in exfoliated buccal cells are useful and minimally invasive methods for monitoring genetic damage in individuals exposed to pesticides. This study provided valuable data for establishing the possible risk to human health associated with pesticide exposure.
Показать больше [+] Меньше [-]Aqueous chlorination of acebutolol: kinetics, transformation by-products, and mechanism Полный текст
2016
Khalit, Wan Nor Adira Wan | Tay, Kheng Soo
This study investigated the reaction kinetics and the transformation by-products of acebutolol during aqueous chlorination. Acebutolol is one of the commonly used β-blockers for the treatment of cardiovascular diseases. It has been frequently detected in the aquatic environment. In the kinetics study, the second-order rate constant for the reaction between acebutolol and chlorine (k ₐₚₚ) was determined at 25 ± 0.1 °C. The degradation of acebutolol by free available chlorine was highly pH dependence. When the pH increased from 6 to 8, it was found that the k ₐₚₚ for the reaction between acebutolol and free available chlorine was increased from 1.68 to 11.2 M⁻¹ min⁻¹. By comparing with the reported k ₐₚₚ values, the reactivity of acebutolol toward free available chlorine was found to be higher than atenolol and metoprolol but lower than nadolol and propranolol. Characterization of the transformation by-products formed during the chlorination of acebutolol was carried out using liquid chromatography-quadrupole time-of-flight high-resolution mass spectrometry. Seven major transformation by-products were identified. These transformation by-products were mainly formed through dealkylation, hydroxylation, chlorination, and oxidation reactions.
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