Results of research on the hazard posed by polycyclic aromatic hydrocarbons contained in the dusts emitted from motor vehicle braking systems have been presented. The polycyclic aromatic hydrocarbons (PAHs) constitute a group of chemical compounds that pose a serious danger to the human health, chiefly because of their carcinogenic properties. Investigations into the issue of environmental pollution with polycyclic aromatic hydrocarbons generated by motor vehicle traffic were carried out in connection with the work being done at PIMOT on systems to reduce dust emission from motor vehicle braking systems. The investigations included determination of PAH contents of the dust emitted from vehicle braking systems as well as the PAH concentrations in the indoor air in a room with the stand for testing dust emissions from braking systems and in the duct to carry away gases from that room. Moreover, the PAH contents of soil were measured in the context of location of the soil sampling points in relation to traffic routes. The PAH contents were measured in Warsaw and in Zabrze. The investigation results confirmed that PAHs considered as being most harmful to the human health due to their carcinogenic properties were actually present in the dusts emitted from braking systems. The PAH contents of soil were found to be very sensitive to the location of the soil sampling points in relation to traffic routes and this is a confirmation of the thesis that motor traffic is an important source of environmental pollution with polycyclic aromatic hydrocarbons.
This study investigates cadmium (Cd) accumulation in the plant leaves of juglans regia (walnut) and cydonia oblanga (quince) trees related to traffic emissions on the highway roadside. The plant leaf samples were collected from 20 sites on the D-100 Highway roadside and washed with deionized water before analyzed. Determination of Cd was carried out using an inductively-coupled plasma-mass spectrometer after microwave digestion of the samples. Cd concentration on the plant leaves was found to be between 0.04–0.11 mg/kg. In order to determine the traffic-based emissions, vehicles were counted and an emission inventory was prepared. 0.18 tons of Cd was found to be delivered into the atmosphere every day. Cd accumulation depends on traffic density because there were no residential area and industrial plants. The distribution of Cd accumulation caused by traffic emissions was mapped by using a geographic information system (GIS). The maps showed that the Cd accumulation was high in the areas near the highway and then gradually decreased by moving away from the highway.
Persistent organic pollutants (POPs) originating from agrochemical industries have become an urgent environmental problem worldwide. Ordinary kriging, as an optimal geostatistical interpolation technique, has been proved to be sufficiently robust for estimating values with finite sampled data in most of the cases. In this study, ordinary kriging interpolation integrate with 3D visualization methods is applied to characterize the monochlorobenzene contaminated soil for an agrochemical industrial site located in Jiangsu province. Based on 944 soil samples collected by Geoprobe 540MT and monitored by SGS environmental monitoring services, 3D visualization in terms of the spatial distribution of pollutants in potentially contaminated soil, the extent and severity of the pollution levels in different layers, high concentration levels and isolines of monochlorobenzene concentrations in this area are provided. From the obtained results, more information taking into account the spatial heterogeneity of soil area will be helpful for decision makers to develop and implement the soil remediation strategy in the future.
Bioremediation is based on microorganisms able to use pollutants either as a source of carbon or in co-metabolism, and is a promising strategy in cleaning the environment. Using soil contaminated with petroleum products from an industrial area in Saudi Arabia (Jubail), and after enrichment with the polycyclic aromatic hydrocarbon (PAH) naphthalene, a Methylobacterium radiotolerans strain (N7A0) was isolated that can grow in the presence of naphthalene as the sole source of carbon. M. radiotolerans is known to be resistant to gamma radiation, and this is the first documented report of a strain of this bacterium using a PAH as the sole source of carbon. The commonly reported Pseudomonas aeruginosa (strain N7B1) that biodegrades naphthalene was also identified, and gas chromatography analyses have shown that the biodegradation of naphthalene by M. radiotolerans and P. aeruginosa did follow both the salicylate and phthalate pathways.
The paper presents preliminary results of investigations on a relationship between turbidity and other quality parameters in the SBR plant effluent. The laboratory tests demonstrated a high correlation between an effluent turbidity and a total suspended solids (TSS) concentration as well as between TSS and COD. Such a relationship would help to continuously monitor and control quality of a wastewater discharge using turbidity measurement.
Vegetable oils belong to a large group of substances consumed on a daily basis. World vegetable oil production is soaring, reducing the popularity of animal fats. Heavy metals pose a threat to human health. It is estimated that about 80% of the daily dose of heavy metals enters the human body through the consumption of food. Hence, it is necessary to monitor their concentrations in food products. Besides, the presence of heavy metals is thought to have possible negative influence on the quality of oils, especially on their taste and smell. Heavy metals may also accelerate the process of the rancidifiction of oils. Rapeseeds, soybean seeds and linseeds were selected for the analysis because they are one of the most popular oilseeds and at the same time they differ in terms of growing conditions. The analyses of different fractions and the ready-made product were also performed. The aim of the study was to determine the variation in concentrations of heavy metals, iron and manganese in different fractions during production. The significant concentrations of iron, manganese and zinc were observed in oilseeds. It was also shown that during different stages of oil refining the concentrations of metals decrease. The concentrations of metals are compared with those reported in literature.
Although the utilization of pesticides accounted for the group of persistent organic pollutants was banned years ago, a count of pesticides are still directly or indirectly a source of contamination in Europe. One of them, simazine is still allowed for use in the United States. Aim of this experiment was development of soil remediation method which could be utilized for degradation triazine class pesticides – simazine was an example used. A method for soil remediation based on ozonation processes in fluidized bed was successfully utilized for removal of simazine from contaminated soil. For the study soil highly contaminated with simazine up to the concentration of 0.05% w/w was used. Determination of the pesticide levels in soil was performed using extraction and gas chromatography. The method allowed 80% reduction of pesticide concentration level. The degradation of pesticide was accompanied with changes of physicochemical parameters of soil, i.e., decrease of pH and a increase of nitrates concentration. Despite changes in physicochemical properties of the soil, the developed method proved to be highly effective and can be successfully applied on an industrial scale.
Cd and Pb concentrations were measured in water, sediment and plant organs collected from selective sites located along the Bogdanka river (Poznań, Poland) in the 2012 growing season. The aim of the investigations was to monitor changes in heavy metal (HM) concentrations in different media over the periods, as well as to evaluate potential of two littoral plants, Phragmites australis and Typha angustifolia, for phytoremediation under natural conditions. Investigations revealed differences in HM concentrations in water and sediments. Higher values were observed in sediments than in water. The decrease in concentrations of both HMs in sediments was noted in two of the three selected water reservoirs during growing seasons, which suggests the possibility of their adsorption and accumulation by aquatic plants. Both investigated plant species accumulated ample amount of Cd and Pb in underground and aboveground plant tissues, however T. angustifolia revealed higher Cd translocation potential than P. australis. The latter revealed higher Pb accumulation in two lakes. Moreover, the translocation ratio was usually higher in spring, especially for Pb, in both plant species. Increasing level of pollution load index in sediment along the Bogdanka watercourse indicates accumulation of measured HMs.
To improve bioremediation of arsenic (As) contamination in soil, the use of microorganisms to efficiently reduce As and their assessment of genetic erosion by DNA damage using genomic template stability (GTS) evaluation and using RAPD markers were investigated. The five sites examined for microorganisms and contaminated soils were collected from affected gold mining areas. The highest As concentration in gold mining soil is 0.72 mg/kg. Microorganism strains isolated from the gold mining soil samples were tested for As removal capacity. Two bacterial isolates were identified by 16S rRNA gene sequence analysis and morphological characteristics as Brevibacillus reuszeri and Rhodococcus sp. The ability to treat As in nutrient agar (NA) at 1,600 mg/L and contaminated soil samples at 0.72 mg/kg was measured at 168 h, revealing more efficient As removal by B. reuszeri than Rhodococcus sp. (96.67% and 94.17%, respectively). Both species have the capacity to remove As, but B. reuszeri shows improved growth compared to the Rhodococcus sp. B. reuszeri might be suitable for adaptation and use in As treatment. The results are in agreement with their genetic erosion values, with B. reuszeri showing very little genetic erosion (12.46%) of culture in As concentrations as high as 1,600 mg/L, whereas 82.54% genetic erosion occurred in the Rhodococcus sp., suggesting that Rhodococcus sp. would not survive at this level of genetic erosion. Therefore, B. reuszeri has a high efficiency and can be used for soil As treatment, as it is capable to tolerate a concentration of 0.72 mg/kg and as high as 1,600 mg/L in NA.
The analysis of particle size in suspensions carried out with use of the laser diffraction method enables us to obtain not only information about the size of particles, but also about their properties, shape and spatial structure, determined basing on fractal dimension. The fractal dimension permits the evaluation of the interior of aggregates, at the same time showing the degree of complexity of the matter. In literature, much attention is paid to the evaluation of the fractal dimension of flocs in activated sludge, in the aspect of control of single processes, i.e. sedimentation, dehydration, coagulation or flocculation. However, results of research concerning the size of particles and the structure of suspensions existing in raw and treated sewage are still lacking. The study presents optical fractal dimensions D3 and particle size distributions measured with use of laser granulometer in raw and treated sewage and activated sludge collected from six mechanical-biological wastewater treatment plants located in the Lower Silesian region. The obtained test results demonstrate that wastewater treatment plants that use both sequencing batch reactors and continuous flow reactors are more efficient at capturing suspension particles of a size up to 30 μm and are characterized by an increased removal of particles of a size ranging from 30 μm to 550 μm to the outflow. Additionally, in the case of samples of treated sewage and activated sludge collected at the same location, at short intervals, similar particle distributions were observed. As far as the analysis of fractal dimensions is concerned, particles contained in the raw sewage suspension were characterized by the lowest values of the fractal dimension (median equals 1.89), while the highest values occurred in particles of activated sludge (median equals 2.18). This proves that the spatial structure of suspension particles contained in raw sewage was similar to a linear structure, with a large amount of open spaces, while the structure of particles contained in the activated sludge suspension was significantly more complex in the spatial aspect.
This study is aimed to investigate culturable airborne bacteria concentrations and the composition of methicillin-resistant staphylococci in eleven different locations on the basis of specific activities conducted within different parts of the European side of Istanbul. The highest bacterial levels were observed at the Bakirkoy station (1 100 CFU/m3) while the second highest levels were found at the Bahcelievler station (1 040 CFU/m3) in October; the lowest levels (10 CFU/m3) were measured at other different stations (Atakoy, Yesilkoy). Fifteen methicillin-resistant isolates [Staphylococcus hominis (n=11), S. cohnii spp. cohnii (n=2), S. sciuri (n=1), S. capitis spp. capitis (n=1)] were identified. The disc diffusion method was used to identify the antimicrobial resistance of these isolates, it was observed that the most common resistance was to penicillin (P) (n=11), doxycycline (DO) (n=4) and tetracycline (T) (n=5). None of the isolates was resistant to imipenem, amoxicillin/clavulanic acid, vancomycin (IPM, AMC, VA). However, multiple antimicrobial resistance was found to be 26.7%. The results of this study revealed the importance of isolated methicillin-resistant staphylococci in the stations with densely active human population and traffic, for public health. As a result, the importance of resting along known shorelines, where culturable airborne bacteria concentrations are much lower, and its importance for human health have been emphasized.
Landfill leachate makes a potential source of ground water pollution. Municipal waste landfill substratum can be used for removal of pollutants from leachate. Model research was performed with use of a sand bed and artificially prepared leachates. Effectiveness of filtration in a bed of specific thickness was assessed based on the total solids content. Result of the model research indicated that the mass of pollutants contained in leachate filtered by a layer of porous soil (mf) depends on the mass of pollutants supplied (md). Determined regression functions indicate agreement with empirical values of variable m′f. The determined regression functions allow for qualitative and quantitative assessment of influence of the analysed independent variables (m′d, l, ω) on values of mass of pollutants flowing from the medium sand layer. Results of this research can be used to forecast the level of pollution of soil and underground waters lying in the zone of potential impact of municipal waste landfill.