Your browser doesn't support javascript.
loading
: 20 | 50 | 100
1 - 7 de 7
1.
Water Res ; 244: 120538, 2023 Oct 01.
Article En | MEDLINE | ID: mdl-37666150

Climate change is creating new challenges for water supply worldwide, making the search for new sources of water vital. As mine water could serve as a potential source, this study investigated the presence of microplastics in water from terminated deep mines in the largest coal basin in the Czech Republic, as well as in water from nearby shallow wells. The particles found were analyzed for size, polymer composition, color and morphology using the ImageJ tool, infrared spectroscopy with Fourier transform (FTIR) and an optical stereomicroscope with a digital camera. Microplastics were detected in all tested sites. Their range accounted for 2.5-17.5 items/L for mine water samples and 2.5-20 items/L for well samples, with fibers being the dominant type. The average width of particles from mine water and wells amounted to 58 µm; 71 µm, length to 655 µm; 501 µm and area to 22,067 µm2; 28,613 µm2, respectively. Blue color was prevalent, among materials, in both cases, plastic coated paper was found dominant to Polyethylene terephthalate (PET), Polyester (PES), Tetrafluoroethylene-perfluoro (Propyl Vinyl Ether) - Copolymer (TFE-PPVE), and polypropylene (PP). The research provides the first evidence of microplastics' presence in underground waters from deep mines and shallow wells in the same area. The data suggest that it is almost impossible to find underground water sources free of microplastic contamination. In this context, atmospheric contamination from mine ventilation and infiltration through terminated mines were identified as potential sources, while infiltration through soil and rock formations is unlikely given the geological composition. The results of this study can serve as a relevant basis for further research on microplastics in mine waters. Additionally, the conclusions can advance the development in remediation technologies of microplastics from deep underground waters and their implementation in practice, particularly in light of upcoming legislation.


Coal Mining , Microplastics , Plastics , Czech Republic , Water
2.
Chemosphere ; 343: 140301, 2023 Dec.
Article En | MEDLINE | ID: mdl-37769922

Considering the well documented, almost ubiquitous nature of microplastics in different environments, the exposure of pregnant women to microplastics may pose risks to the unborn children. The study focused on investigating the presence of microplastics in amniotic fluid and placenta, and brings the first evidence of the simultaneous presence of microplastics and additives in both human amniotic fluid and placentas. In total, 20 samples of amniotic fluid and placenta from 10 patients were analyzed for the presence of microplastics and plastic additives by Fourier transform infrared spectroscopy - attenuated total reflectance (FTIR-ATR) after alkaline digestion with KOH. In 9 out of 10 patients, microplastics or additives were found in amniotic fluid, placenta, or both. Specifically, 44 particles of microplastics and polymer additives were identified in all samples. Chlorinated Polyethylene (CPE) and Calcium zinc PVC Stabilizer with particle sizes between 10 and 50 µm prevailed. Although all women involved in this study, who provided placenta and amniotic fluid samples, experienced physiological, singleton pregnancies complicated with preterm prelabour rupture of membranes (PPROM), it is too early to draw any conclusions and more research is needed.

3.
Sci Rep ; 11(1): 18989, 2021 09 23.
Article En | MEDLINE | ID: mdl-34556770

Solid particles, predominantly in micron and submicron sizes, have repeatedly been observed as a threat to a human health unique compared to the other textures of the same materials. In this work, the hypothesis the solid metal-based particles play a role in the pathogenesis of chronic hypertrophic rhinitis was investigated in patients who had not responded positively to medication. In the group of 40 randomly selected patients indicated for surgical mucotomy, the presence of solid micro- and submicron particles present in their nasal mucosa was assessed. For comparison, a set of 13 reference samples from patients without diagnosed chronic hypertrophic rhinitis was evaluated. The analysis was performed using Raman microspectroscopy. The advantage of this method is the direct identification of compounds. The main detected compounds in the mucosa samples of patients with chronic hypertrophic rhinitis were TiO2, carbon-based compounds, CaCO3, Ca(Fe, Mg, Mn)(CO3)2 MgCO3, Fe2O3, BaSO4, FeCO3 and compounds of Al and Si, all of which may pose a health risk to a living organism. In the reference samples, only TiO2 and amorphous carbon were found. In the control group mucosa, a significantly lower presence of most of the assessed compounds was found despite the longer time they had to accumulate them due to their higher mean age. Identification and characterisation of such chemicals compounds in a living organism could contribute to the overall picture of the health of the individual and lead to a better understanding of the possible causes not only in the chronic hypertrophic rhinitis, but also in other mucosal and idiopathic diseases.


Air Pollutants/chemistry , Nasal Mucosa/pathology , Rhinitis/etiology , Adult , Aged , Air Pollutants/adverse effects , Air Pollutants/isolation & purification , Case-Control Studies , Chronic Disease , Endoscopy , Female , Humans , Hypertrophy/etiology , Hypertrophy/pathology , Hypertrophy/surgery , Male , Middle Aged , Nasal Mucosa/surgery , Particle Size , Prospective Studies , Rhinitis/pathology , Rhinitis/surgery , Young Adult
4.
Article En | MEDLINE | ID: mdl-34300059

Plastic particles smaller than 5 mm, i.e., microplastics, have been detected in a number of environments. The number of studies on microplastics in marine environments, fresh water, wastewater, the atmosphere, and the human body are increasing along with a rise in the amounts of plastic materials introduced into the environment every year, all contributing to a range of health and environmental issues. Although the use of primary microplastics has been gradually reduced by recent legislation in many countries, new knowledge and data on these problems are needed to understand the overall lifecycle of secondary microplastics in particular. The aim of this review is to provide unified information on the pathways of microplastics into the environment, their degradation, and related legislation, with a special focus on the methods of their sampling, determination, and instrumental analysis. To deal with the health and environmental issues associated with the abundance of microplastics in the environment, researchers should focus on agreeing on a uniform methodology to determine the gravity of the problem through obtaining comparable data, thus leading to new and stricter legislation enforcing more sustainable plastic production and recycling, and hopefully contributing to reversing the trend of high amounts of microplastics worldwide.


Microplastics , Water Pollutants, Chemical , Environmental Monitoring , Fresh Water , Humans , Plastics , Water Pollutants, Chemical/analysis
5.
Life (Basel) ; 11(3)2021 Mar 14.
Article En | MEDLINE | ID: mdl-33799430

This article summarizes the results of a research study that was focused on the possibility of removing Cr (VI) from aqueous solution, using low-cost waste biomaterial in a batch mode. A set of seven biosorbents was used: Fomitopsis pinicola, a mixture of cones, peach stones, apricot stones, Juglans regia shells, orange peels, and Merino sheep wool. Three grain fractions (fr. 1/2, fr. 0.5/1.0, and fr. 0/0.5 mm) of biosorbents were studied. The aim was to find the most suitable biosorbent that can be tested with real samples. The influence of other factors on the course of biosorption was studied as well (chemical activation of the biosorbent, pH value, rotation speed during mixing, temperature, and the influence of biosorbent concentration). The use of chemical activation and adjustment of the pH to 1.1 to 2.0 make it possible to increase their sorption capacity and, for some biosorbents, to shorten the exposure times. Two kinetic models were used for the analysis of the experimental data, to explain the mechanism of adsorption and its possible speed control steps: pseudo-first and pseudo-second-order. The pseudo-second-order kinetic model seems to be the most suitable for the description of the experimental data. The thermodynamic parameters suggest that the biosorption was endothermic and spontaneous. In the biosorption equilibrium study, the adsorption data were described by using Langmuir and Freundlich adsorption isotherms. The Langmuir model was applicable to describe the adsorption data of all biosorbents. Both models are suitable for chemically treated sheep fleece and peach stones.

6.
Article En | MEDLINE | ID: mdl-33921692

Water pipe sediment removal should be implemented as an integral part of water mains maintenance in order to steadily supply consumers with drinking water of high quality. Considering the number of different water pipe sediment removal methods, the article aims to evaluate the currently used methods to remove water pipe sediment from the pipes of the drinking water distribution system. The evaluation compares the implementation requirements of each method as well as the quality and the quantity of the removed products. The tested methods were unidirectional flushing, Comprex®, and Ice Pigging®. The results of the comparison are expressed in terms of total suspended solids (TSS) recovery, metals mass concentration and water consumption. Since contamination can settle along the entire surface of the pipeline, it is most appropriate to recalculate the results per unit area of the pipeline. The results point at the following efficiency the Comprex® method was the most efficient in removing TSS, Ice Pigging® was the next and unidirectional flushing removed a negligible amount of TSS compared to the other two methods. The absolute recovery of TSS was 0.12-3.01 g·m-2 in unidirectional flushing of plastic pipes, 1.58-8.54 g·m-2 in unidirectional flushing of metal pipes, 4.36-47.53 g·m-2 in Ice Pigging®, and 5.19-69.23 g·m-2 in Comprex®. The composition of the sediment was strongly influenced by particle origin: Pipe material affected the crystalline phase of the sediment and the water source and the age of the pipe affected the amorphous phase of the sediment. Therefore, it was found that evaluation of efficiency based on the amount of TSS removed is only suitable for sites that meet the same conditions as pipe material, water source and ideally the pipe age. It has further been found that the Comprex® method can be advantageously used in real conditions to clean pipes with insufficient hydraulic conditions (such as with a high level of incrustation), as the cleaning has low water flow velocity requirements.


Drinking Water , Metals , Water Microbiology , Water Supply
7.
Article En | MEDLINE | ID: mdl-33023188

This article deals with the possibility of using a biosorbent in the form of a mixture of cones from coniferous trees to remove the residual concentration of hazardous metals contained in hazardous waste, which is disposed of in a neutralization station. The efficiency of the tested biosorbent in removing Ni, Zn, Cu, and Fe was monitored here. Laboratory research was carried out before the actual testing of the biosorbent directly in the operation of the neutralization station. With regard to the planned use of the biosorbent in the operational test, the laboratory experiments were performed in a batch mode and for the most problematic metals (Ni and Zn). The laboratory tests with real wastewater have shown that the biosorbent can be used to remove hazardous metals. Under the given conditions, 96% of Ni and 19% of Zn were removed after 20 min when using NaOH activated biosorbent with the concentration of 0.1 mol L-1. The inactivated biosorbent removed 93% of Ni and 31% of Zn. The tested biosorbent was also successful during the operational tests. The inactivated biosorbent was applied due to the financial costs. It was used for the pre-treatment of hazardous waste in a preparation tank, where a significant reduction in the concentration of hazardous metals occurred, but the values of Ni, Cu, and Zn still failed to meet the emission limits. After 72 h, we measured 10 mg L-1 from the original 4,056 mg L-1 of Ni, 1 mg L-1 from the original 2,252 mg L-1 of Cu, 1 mg L-1 from the original 4,020 mg L-1 of Zn, and 7 mg L-1 from the original 1,853 mg L-1 of Fe. However, even after neutralization, the treated water did not meet the emission limits for discharging into the sewer system. The biosorbent was, therefore, used in the filtration unit as well, which was placed in front of the Parshall flume. After passing through the filtration unit, the concentrations of all the monitored parameters were reduced to a minimum, and the values met the prescribed emission limits. The biosorbent was further used to thicken the residual sludge in the waste pre-treatment tank, which contributed to a significant reduction in the overall cost of disposing of residual hazardous waste. This waste was converted from liquid to solid-state.


Metals, Heavy/analysis , Waste Disposal, Fluid/methods , Water Pollutants, Chemical/analysis , Adsorption , Czech Republic , Metals , Wastewater , Zinc/analysis
...