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Dichlorodiphenyltrichloroethane (DDT) is an organochloride pesticide with a global impact on agriculture. Despite the international ban on this pesticide in 2001, DDT is still illegally used for malaria control in some parts of the world, such as India and South Africa. The presence of DDT and its metabolites in waters, soil, and sediments continue to adversely affect living organisms. Understanding the toxic effects of DDT is crucial for global environmental health. The goal of this study was to investigate the toxicity of DDT in E. coli ATCC-25922, Sarcina spp., ATCC-35659, Enterobacter homaechei LBM ATCC-700323, Staphylococcus aureus ATCC-25923 and Candida albicans ATCC-1023. To confirm oxidative stress as a mechanism of toxicity, sodA promoter induction in the Escherichia coli sodA:luxCDABE biosensor strain and ROS (Radical Oxygen Species) synthesis in E. coli ATCC- 25922 strain, across various DDT concentrations (10, 1, 0.1, and 0.01 mg/L) were measured. The results showed that DDT in the range of applied concentrations shows a toxic effect on bacteria/fungi. Analysis of sodA promoter induction and ROS synthesis values in E. coli strains showed an increase in these indicators following exposure to the tested DDT concentrations. The results confirmed the validity of the hypothesis that the molecular mechanism of DDT toxicity is by induction of oxidative stress. Therefore, the need to develop more effective methods of removing DDT from wastewater and water and reducing the transport of this pesticide into the environment is justified. Moreover, recent evidence has increasingly confirmed positive correlations between human exposure to DDT and the development of cancers. [ABSTRACT FROM AUTHOR]

Heavy metals play a crucial role in the environment due to their toxicity, persistence, and bioaccumulation ability, which can lead to severe ecological and health risks. This study aimed to investigate the impact of urbanization and agricultural practices on the heavy metal content in the sediments of the Bug River catchment. To this end, 96 surface sediment samples were collected from various points in the Bug River catchment, including from urban, agricultural, and forested areas. The samples for laboratory analysis were collected in July 2018, 2019, and 2020 in the Polish part of the Bug River watershed. Heavy metal (Zn, Pb, Cr, Ni, Cu, Fe, Mn, and Cd) concentrations were determined using atomic absorption spectroscopy (AAS). The geoaccumulation index (Igeo), contamination factor (CF), and pollution load index (PLI) were used to assess the degree of sediment contamination. The results indicate higher concentrations of heavy metals in urban sediments, where cadmium concentrations reached up to 2.5 mg/kg, compared to agricultural and forested areas, where concentrations were significantly lower. The average Igeo value for cadmium was 0.24 in agricultural areas and 0.15 in urban areas, suggesting the predominance of anthropogenic influences over natural sources. The highest PLI values were found in urban areas, reaching a maximum of 0.33, indicating higher pollution levels. Statistical analysis revealed that urban emissions and agricultural activities significantly influenced the presence of these metals in the Bug River sediments. This study's conclusions emphasize that effective river water quality management requires continuous monitoring and an understanding of anthropogenic and natural pollution sources. The results contribute to a better understanding the interactions between human activities and water quality, crucial for planning protection and remediation strategies. Additionally, this study provides critical insights into optimizing pollution management strategies and developing remediation methods, serving local and regional policymakers in planning protective actions. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Environmental Protection is the property of Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The most common technology for the recovery of energy and valuable materials from sewage sludge is anaerobic digestion (AD). Ensuring thermophilic conditions during AD has been proven to cause process intensification and an improvement in its final outcomes. Nonetheless, the search is underway for other methods to bolster the effectiveness of the AD of aerobic granular sludge (AGS), which is characterized by a compact and complex structure. A prospective AGS pre-treatment technology entails the use of solidified carbon dioxide (SCO2). The present study focused on an evaluation of the AGS pre-treatment with SCO2 on the thermophilic AD technological effects. It evaluated the effect of the SCO2 pre-treatment method on changes in the concentrations of organic and biogenic compounds in the dissolved phase and the yield and kinetics of biogas and methane production in periodical reactors, as well as enabled the development of an empirical organizational model of biogas production. SCO2 introduced to AGS caused an increase in the content of COD, N-NH4+, and P-PO43− in the AGS dissolved phase at SCO2/AGS volumetric ratios ranging from 0 to 0.3. A further increase in the SCO2 dose did not cause any statistically significant differences in this respect. The highest biogas and methane yields were obtained at SCO2/AGS of 0.3 and reached 482 ± 21 cm3/gVS and 337 ± 14 cm3/gVS, respectively. The higher SCO2 doses used led to a significant decrease in the pH value of the AGS, which, in turn, contributed to a decreasing CH4 concentration in the biogas. [ABSTRACT FROM AUTHOR]

This paper presents artificial neural network (ANN) model of wastewater treatment plant, which was used for average monthly concentrations of N-NH4+, N-NO3-, N-NO2-, total Kiejdahl nitrogen (TKN), PO43- and SO42- approximation. ANN model was developed for wastewater treatment plant located in Bystre, Poland which treats municipal wastewater with a share of dairy wastewater. The object was chosen because of the unique location, in the Great Mazury Lakes area and the need for its special environmental protection. Input layer of developed ANN model consisted of BOD, COD, concentrations of total nitrogen and total phosphorus, total organic carbon, sulphates, wastewater temperature and pH., The developed model reflected extreme values observed during study period. Average error percentage with which output variables were approximated equalled to 35.35%; 8.99%; 21.23%; 5.08%; 10.99%; 3.02% respectively for N-NH4+, N-NO3-, N-NO2-, TKN, PO43- and SO42-.

Wastewater treatment is a process which aims to reduce the concentration of pollutants in wastewater to the level allowed by current regulations. This is to protect the receivers which typically are rivers, streams, lakes. Examination of the quality of treated wastewater allows for quick elimination of possible negative effects, and the study of water receiver prevents from excessive contamination. The paper presents the results of selected physical and chemical parameters of treated wastewater from the largest on the region in north-eastern Poland city of Bialystok municipal wastewater treatment and Biała River, the receiver. The samples for research were taken 3–4 a month in 2015 from two points: before and after discharge. The impact of the wastewater treatment plant on the quality of the receiver waters was studied by using non-parametric Wilcoxon test. This test determined whether the analyzed indicators varied significantly depending on different sampling points of the river, above and below place of discharge of treated wastewater. These results prove that the treated wastewater does not affect the water quality in the Biała River.

Copyright of Archives of Environmental Protection is the property of Polish Academy of Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Annual Set the Environment Protection / Rocznik Ochrona Środowiska is the property of Koszalin University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The purpose of this paper was to determine changes in loads of N-NH4+, S-SO42, P-PO43-, N-NO3-, Pog, Cl-, Ca2+, Mg2+, and their origin in waters outflowing from Supraśl catchment. Research was carried out in the period from 2001 to 2009 in three measurement points located around Gródek, Nowodworce and Dzikie. Obtained values of specific load were raging for: N-NH4+0.051÷2.094 kg N-NH4 +·ha-1·year-1, S-SO4 2- 16.50÷30.00 kg S-SO4 2-·ha-1·year-1, P-PO4 3- 0.17÷0.45 kg P-PO4 3·ha-1·year-1, Pog 0.44÷0.78 kg P·ha-1·year-1, Cl- 14.58÷26.80 kg Cl-·ha-1·year-1, Ca2+ 68.2÷77.1 kg Ca2+·ha-1·year-1, Mg2+ 9.57÷12.29 kg Mg2+·ha-1·year-1. In addition, linear Pearson correlation coefficients were calculated between specific loads of individual components and fertilization form in each measuring point. There were obtained statistically significant correlations between NPK fertilization and specific loads of N-NH4 +, Pog, Cl-, Ca2+ i Mg2+ and between manure fertilization and S-SO4 2-, Ca2+ i Mg2+. [ABSTRACT FROM AUTHOR]

The purpose of the study was to determine seasonal changes of ammonia nitrogen, nitrate nitrogen, total nitrogen, phosphate and total phosphorus in the years 2003-2009 in the river Supraśl. For this purpose a monitoring network was created with selected three control points on the basis of which the assessment was made. Control points were located near Gródek, Nowodworce and Dzikie. The research results were averaged for each month. On this basis the assessment of seasonal changes of nitrogen and phosphorus forms in the river Supraśl has been carried out. Research and analysis showed that the concentration of nitrogen and phosphorus in waters of Supraśl were characterized by a clear seasonal variation, the highest concentration of nitrogen was observed in January and February and the lowest in June in each of the analyzed points, the course of changes in the concentration of nitric and total nitrogen in March were different from the general course of reigning changes in their concentrations in surface waters. [ABSTRACT FROM AUTHOR]