Methodology of Research in Micropollutants – Heavy Metals

1982 ◽  
Vol 14 (12) ◽  
pp. 107-125 ◽  
Author(s):  
Roland Wollast

A comparison of the concentration of dissolved and of particulate heavy metals in the aquatic system indicates that these elements are strongly enriched in the suspended matter. The transfer between the aqueous phase and the solid phase may be due to dissolution-precipitation reactions, adsorption-desorption processes or biological processes. When these processes are identified, it is further possible to develop mathematical models which describe the behaviour of these elements. The enrichment of heavy metals in the particulate phase suspended or deposited and in aquatic organisms constitutes a powerful tool in order to evaluate sources of pollution.

2020 ◽  
Vol 99 (4) ◽  
pp. 363-367
Author(s):  
Olga M. Zhurba ◽  
N. V. Efimova ◽  
S. S. Khankhareev ◽  
A. N. Alekseyenko ◽  
A. V. Merinov ◽  
...  

Introduction. On the territory with a resistant snow cover, atmospheric pollution accumulates over several months; solid precipitation in the form of snow is an indicator object for assessing the state of the urban environment. Materials and methods. The sampling of snow was carried out on trial plots close to the monitoring points of atmospheric air and reflecting the influence of various stationary and mobile sources of pollution. The methods of gas chromatography-mass spectrometry and the atomic absorption spectrometry were used. Results. The results were obtained on the content of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in snow cover to identify risk zones in the city of Ulan-Ude of the Republic of Buryatiya. The widest range of metals is recorded at points located near a major traffic interchange and in a residential area near the low-rise buildings of the private sector. The determined PAHs in large quantities were established to be contained in the solid sediment of snow samples. Discussion. Snow cover is a depositing and transit component of the environment. Its study gives important information about the chemical state of industrial ecosystems. About 30 thousand tons of chemical impurities enter the air basin of Ulan-Ude from stationary sources per year. Emissions of the total amount of hydrocarbons averaged of 1,741.96 tons over the study period, soot - 822.41 tons, which is by tens and hundreds times higher than that of other toxic substances, therefore, the PAH content in snow samples is higher than that of heavy metals. Conclusion. The accumulation of chemicals of 13 priority PAHs, of which 60-80% of the total amount falls on 3-,4- nuclear counterparts (phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene) occurs in accumulating media. PAHs are associated with water-insoluble (solid phase) PAHs, which indicates to the unity of the main source of pollution (vehicle exhaust gases).


2020 ◽  
Vol 99 (4) ◽  
pp. 363-367
Author(s):  
Ольга Михайловна Журба ◽  
Н. В. Ефимова ◽  
С. С. Ханхареев ◽  
А. Н. Алексеенко ◽  
А. В. Меринов ◽  
...  

Introduction. On the territory with a resistant snow cover, atmospheric pollution accumulates over several months; solid precipitation in the form of snow is an indicator object for assessing the state of the urban environment. Materials and methods. The sampling of snow was carried out on trial plots close to the monitoring points of atmospheric air and reflecting the influence of various stationary and mobile sources of pollution. The methods of gas chromatography-mass spectrometry and the atomic absorption spectrometry were used. Results. The results were obtained on the content of polycyclic aromatic hydrocarbons (PAHs) and heavy metals in snow cover to identify risk zones in the city of Ulan-Ude of the Republic of Buryatiya. The widest range of metals is recorded at points located near a major traffic interchange and in a residential area near the low-rise buildings of the private sector. The determined PAHs in large quantities were established to be contained in the solid sediment of snow samples. Discussion. Snow cover is a depositing and transit component of the environment. Its study gives important information about the chemical state of industrial ecosystems. About 30 thousand tons of chemical impurities enter the air basin of Ulan-Ude from stationary sources per year. Emissions of the total amount of hydrocarbons averaged of 1,741.96 tons over the study period, soot - 822.41 tons, which is by tens and hundreds times higher than that of other toxic substances, therefore, the PAH content in snow samples is higher than that of heavy metals. Conclusion. The accumulation of chemicals of 13 priority PAHs, of which 60-80% of the total amount falls on 3-,4- nuclear counterparts (phenanthrene, anthracene, fluoranthene, pyrene, benzo(a)anthracene, chrysene) occurs in accumulating media. PAHs are associated with water-insoluble (solid phase) PAHs, which indicates to the unity of the main source of pollution (vehicle exhaust gases).


2019 ◽  
Author(s):  
V.B. Kalmanova

В статье представлены результаты исследования экологогеохимического состояния снежного покрова как индикатора качества атмосферного воздуха г. Биробиджана. Выявлены основные природные и антропогенные факторы, предопределяющие экологическое состояние городской территории в зимний период (климатические, планировочная структура, стационарные и мобильные источники загрязнения). Определено, что выбросы основных загрязнителей во время отопительного сезона превышает летний в 6,5 раз. Проведены геохимические исследования снежного покрова на 60 экспериментальных площадках, заложенных в различных функциональных зонах города. Выявлено значительное превышение тяжелых металлов над фоновым уровнем: железа до 60, марганца до 50, меди до 40, цинка до 20, никеля до 12, свинца до 10, кобальта до 6 раз. С 2003 по 2018 годы содержание химических элементов в снеге увеличилось в 2 раза за счет мобильных источников загрязнения, ТЭЦ, котельных. Проведена сравнительная характеристика накопления тяжелых металлов в снеге за 2003 и 2018 годы и установлен ранжированный ряд загрязняющих токсичных веществ. Разработана шкала оценки загрязнения депонирующих сред по суммарному показателю концентрации тяжелых металлов, согласно которой в Биробиджане выявлено 5 уровней загрязнения снежного покрова. В целом экологическое состояние урбанизированной территории признано неудовлетворительным (8 площади территории относится к очень высокому, 14 к высокому, 21 к выше среднему, 27 к среднему уровням загрязнения, 30 к относительно чистым районам города). По полученным результатам разработана карта в программе ArcView GIS Экологогеохимическое районирование территории г. Биробиджана по уровню загрязнения снежного покрова с выделением наиболее загрязненных участков (70 от общей площади города является загрязненной). По результатам проведенных исследований предложены конструктивные методы планирования урбанизированной территории с целью улучшения ее экологического состояния: проведение геомониторинга (контроль загрязнения снежного покрова и своевременный его вывоз на специально оборудованные полигоны). Snow cover is taken as an indicator of air quality using Birobidzhan, a middlesize city in the Russian Far East, as a case study. The main natural and manmade determinants influencing the ecological state of the urban area in winter are identified: climate, a planning structure, and the stationary and mobile sources of pollution. During the heating season the emission of major pollutants exceeds the summer level by 6.5 times. The geochemical study of snow cover was performed at 60 experimental sites in different functional urban areas. A significant excess of heavy metals over the regional background level was revealed: iron up to 60 times, manganese up to 50, copper up to 40, zinc up to 20 , nickel up to 12, lead up to 10, cobalt up to 6 times. From 2003 to 2018 the content of chemical elements in snow increased in 2 times due to the mobile sources of pollution, thermal power plants, and boilers. The comparative characteristic of accumulation of heavy metals in snow for 2003 and 2018 is carried out, and the ranked number of polluting toxic substances is established. The scale of pollution assessment in depositing environments was developed using the cumulative indicator of heavy metal concentration. Five levels of snow cover pollution are found in Birobidzhan: low, moderate, above moderate, high and very high. As a whole, the ecological state of the urban area is considered as unsatisfactory (8 of the area with a very high level of pollution, 14 with high, 21 above moderate, 27 a moderate level of pollution, 30 a relatively clean area). According to the results, a map was developed in the ArcView GIS program Ecological and geochemical zoning of Birobidzhan, using the level of the snow cover pollution with the allocation of the most polluted areas (70 of the total area of the city is polluted). According to the results, a constructive method of planning in an urban area is proposed in order to improve its environmental condition: geomonitoring as a control of pollution in snow cover and its prompt removal to specially equipped landfills.


2019 ◽  
Vol 31 (11) ◽  
pp. 2527-2531
Author(s):  
St. Fauziah ◽  
N.H. Soekamto ◽  
P. Budi ◽  
P. Taba

Molecularly imprinted polymers (MIP) as an adsorbent has been synthesized using β-sitosterol as molecule template on free radical polymerization reaction. The capacity and selectivity of the adsorption from MIP to β-sitosterol was studied in this study. The β-sitosterol concentration in the adsorption-desorption test and the MIP selectivity test were analyzed by UV-visible and HPLC. The MIP obtained from the synthesis results in a high adsorption capacity. Based on the Freundlich adsorption isothermal equation, the adsorption capacity (k) was found to be 1.24 mg/g. The MIP can adsorb 100 % β-sitosterol while cholesterol was only 3 %. The MIP is most selective to β-sitosterol, therefore, has high potential to apply as adsorbent at solid phase extraction method to isolate β-sitosterol from sample extract.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shaobin Zhang ◽  
Claudia Contini ◽  
James W. Hindley ◽  
Guido Bolognesi ◽  
Yuval Elani ◽  
...  

AbstractThere are increasing efforts to engineer functional compartments that mimic cellular behaviours from the bottom-up. One behaviour that is receiving particular attention is motility, due to its biotechnological potential and ubiquity in living systems. Many existing platforms make use of the Marangoni effect to achieve motion in water/oil (w/o) droplet systems. However, most of these systems are unsuitable for biological applications due to biocompatibility issues caused by the presence of oil phases. Here we report a biocompatible all aqueous (w/w) PEG/dextran Pickering-like emulsion system consisting of liposome-stabilised cell-sized droplets, where the stability can be easily tuned by adjusting liposome composition and concentration. We demonstrate that the compartments are capable of negative chemotaxis: these droplets can respond to a PEG/dextran polymer gradient through directional motion down to the gradient. The biocompatibility, motility and partitioning abilities of this droplet system offers new directions to pursue research in motion-related biological processes.


2013 ◽  
Vol 67 (11) ◽  
pp. 2622-2629 ◽  
Author(s):  
Chandima Gunawardana ◽  
Ashantha Goonetilleke ◽  
Prasanna Egodawatta

The research study discussed in the paper investigated the adsorption/desorption behaviour of heavy metals commonly deposited on urban road surfaces, namely, Zn, Cu, Cr and Pb, for different particle size ranges of solids. The study outcomes, based on field studies and batch experiments, confirmed that road deposited solids particles contain a significantly high amount of vacant charge sites with the potential to adsorb additional heavy metals. Kinetic studies and adsorption experiments indicated that Cr is the most preferred metal element to associate with solids due to the relatively high electronegativity and high charge density of trivalent cation (Cr3+). However, the relatively low availability of Cr in the urban road environment could influence this behaviour. Comparing total adsorbed metals present in solids particles, it was found that Zn has the highest capacity for adsorption to solids. Desorption experiments confirmed that a low concentration of Cu, Cr and Pb in solids was present in water-soluble and exchangeable form, whilst a significant fraction of adsorbed Zn has a high likelihood of being released back into solution. Among heavy metals, Zn is considered to be the most commonly available metal among road surface pollutants.


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