A significant amount of artificial radionuclides has been introduced into the environment in the last century during atmospheric nuclear weapons tests and the Chernobyl accident. In this study, we investigated the temporal changes of concentrations and amounts of these radionuclides (⁹⁰Sr and ¹³⁷Cs) in surface water and river bed sediments. In order to evaluate the artificial radionuclide contamination diminution, we used and compared two different approaches: using a kinetic equation of the first order and, if needed, dividing the monitored period into two intervals, and in addition expressing the whole process in one equation with a series of exponential functions. Effective ecological half-lives were estimated as rates of decrease. In most cases, the ecological processes were proven to affect the radionuclide removal from the hydrosphere besides their radioactive decay. Furthermore, based on the assessment made, the ⁹⁰Sr and ¹³⁷Cs data were extrapolated and the radionuclide concentrations, which occurred in the hydrosphere after the fallout deposition in 1986, were estimated.

Eutrophication related to excess phosphorus (P) loadings continues to be an important issue for watersheds in North Carolina and other regions. Identifying the contributing sources of P in nutrient-sensitive waters is important for improving water quality. Prior studies have indicated that onsite wastewater treatment systems (OWS) can be a contributing source of P to surface waters, but more information is needed regarding their contribution relative to other wastewater treatment technologies. The goal of this study was to determine if P concentrations in groundwater and surface water were significantly different in a coastal plain watershed served by OWS in comparison to a watershed served by a municipal sewer system (MWS). Groundwater P concentrations were monitored at ten residential sites (five5 OWS and five MWS) once during each season (four times), and stream P concentrations and watershed exports were monitored monthly for 1 year (August 2011–August 2012). Groundwater in the OWS watershed had higher P concentrations than the MWS watershed. Stream P concentrations and P exports were also elevated in the OWS watersheds. However, the OWS were more efficient at reducing P prior to surface water discharge than the wastewater treatment plant that served the MWS watershed. The site-scale and watershed-scale P treatment efficiencies of OWS were between 73 and 99 %, whereas P treatment efficiency for the wastewater treatment plant was 54 %. While the OWS were efficient at reducing P concentrations and loads, OWS were still significant sources of P exports from the studied watershed. Potential contributions of P from OWS should be included in watershed nutrient management strategies along with other known sources such as agriculture and urban runoff if the strategies are to be considered comprehensive.

The elimination of five selected emerging contaminants (1-H-benzotriazole, N,N-diethyl-m-toluamide (DEET), chlorophene, 3-methylindole, and nortriptyline HCl) dissolved in different water matrices (surface water and secondary effluents) was carried out by sequential membrane filtration and chemical oxidation processes. First, a membrane filtration (ultrafiltration (UF) or nanofiltration(NF)) pre-treatment was conducted, and both permeate and retentate were afterwards treated by chemical oxidation, using ozone or chlorine. The application of UF and especially of NF provided a large volume of permeate, whose quality can be improved by a chemical treatment to completely remove residual contaminants except 1-H-benzotriazole. Chlorination and especially ozonation have demonstrated to be effective for the reduction of emerging contaminants in the concentrated stream, thus generating an effluent that might be recycled to the activated sludge treatment in the wastewater treatment plants (WWTP). In a second group of experiments, a chemical oxidation pre-treatment (by using ozone, chlorine, O₃/H₂O₂, ultraviolet (UV) radiation, or UV/H₂O₂) was applied followed by a nanofiltration process. Results of removals and rejection coefficients for the emerging contaminants showed that the chemical pre-treatment exerted a positive influence on the subsequent NF process, not only in terms of ECs removal but also of dissolved organic carbon content (DOC) reduction. While global removals higher than 97 % were reached for DEET, chlorophene, 3-methylindole, and nortriptyline HCl, lower values were obtained for 1-H-benzotriazole, especially for chlorine pre-treatment and in those water matrices with high content of natural organic matter. Therefore, both sequential treatments are promising to remove the selected micropollutants while reducing the chlorine doses needed to achieve final water disinfection.

Lead contamination remains a persistent global environmental problem, the hazards of which are often difficult to identify without specific and targeted research. This study examines environmental contamination arising from the widespread use of lead solder in the joints of large gravity water supply pipelines. Contamination of adjacent grazing lands and subsequent poisoning of domestic livestock are evaluated. In particular, the study demonstrates that replacement of lead joints along an above ground 70 km water supply pipeline in central New South Wales (NSW), Australia, has caused soil lead contamination of up to 20,600 mg/kg. Contamination either side of the pipeline corridor extends to ∼10 m before surface soil lead values correspond more closely to natural background concentrations of 26 mg/kg. The estimated total volume of contaminated soil requiring remediation is 21,000 m³. Contamination is linked to toxicity and mortality in several farm animals and to elevated contamination of grass fodder (up to 50 mg/kg of lead) close to the pipeline. Other similar large-scale above ground reticulation systems in the Sydney (NSW) Metropolitan region and adjacent to the 560 km long Kalgoorlie (Western Australia) Golden Pipeline are shown to present similar environmental hazards. The use of lead solder joints in other international large scale reticulation networks are also identified, demonstrating that this specific anthropogenic hazard is likely to be a more global problem, which has not has been detailed in the research literature to any significant extent.

Soil metal contamination represents serious threats to plant ecosystem sustainability. Knowledge of metal distribution in plants and the effects of long-term exposure to high levels of metals on cytological stability in Deschampsia cespitosa and Populus tremuloides population is limited. The objective of the present study was to determine how D. cespitosa and P. tremuloides plants cope with soil metal contamination. The effects of high copper (Cu) and nickel (Ni) soil concentrations on cytological stability were also analyzed. The results provide strong evidence that D. cespitosa plants cope with metal contaminations by accumulating them in their root system with limited translocation to their aerial plant parts. Metal bioaccumulation factors were high with values of 5.53 (Cu), 35.19 (Fe), 151.21 (Mg), 24.38 (Ni), and 27.42 (Zn). On the other hand, the bioaccumulation factors in P. tremuloides were 0.42 (Cu), 1.67 (Fe), 4.77 (Mg), 0.94 (Ni), and 5.53 (Zn). The translocation factors (TFs) from roots to leaves for poplar (P. tremuloides) were high for Ni (8.38) and low for Cu (0.71). Cytological analysis clearly showed that long exposure of roots to high levels of metal contamination lead to significant mitotic disruption. Overall, 100 % of the plants from metal-contaminated sites showed a high level of mixoploidy compared to 17 % from the reference sites. Lagging chromosomes in mitotic anaphase were observed in most of the plants from metal-contaminated sites. These mitotic abnormalities appear to have no detectable effects on plant growth and survival.

Directional variograms, along the soil profile, can be useful and precise tool that can be used to increase the precision of the assessment of soil pollution. The detail analysis of spatial variability in the soil profile can be also an important part of the standardization of soil magnetometry as a screening method for an assessment of soil pollution related to the dust deposition. The goal of this study was to investigate the correlation between basic parameters of spatial correlations of magnetic susceptibility in the soil profile, such as a range of correlation and a sill, and selected magnetometric indicators of soil pollution. Magnetic indicators were an area under the curve of magnetic susceptibility versus a depth in the soil profile, values of magnetic susceptibility at depths ranging from 1 to 10 cm, and maximum and background values of magnetic susceptibility in the soil profile. These indicators were previously analyzed in the literature.The results showed that a range of correlation of magnetic susceptibility was significantly correlated with magnetic susceptibility measured at depths 1, 2, and 3 cm. It suggests that a range of correlation is a good measure of pollutants’ dispersion in the soil profile. The sill of the variogram of magnetic susceptibility was found to be significantly correlated with the area under the curve of plot of magnetic susceptibility that is related to the soil pollution. In consequence, the parameters of microscale spatial variability of magnetic susceptibility in s soil profile are important measures that take into consideration the spatial aspect of s soil pollution.

Natural organic matter (NOM) interaction with corrosion sediments is important because it can adversely affect the behaviour of many organic and inorganic pollutants in drinking water distribution systems. NOM accumulation onto corrosion sediments can cause serious problems for water supply, such as bacteria regrowth and deterioration of water quality. Corrosion sediments have different structures from the well-known iron oxides. The interaction among corrosion sediments and water organic matter can also differ. The main goal of this work was to understand the adsorption mechanism of the processes of NOM interaction with corrosion sediments. Fulvic acid (FA) isotherms on corrosion sediments in logarithmic coordinates of the Freundlich equation have different segments with different slopes, representing the non-adsorbed and adsorbed conditional component of the FA. The formation of structures with a molecular weight higher than the initial FA was observed. FA adsorption on corrosion sediments depends on time. Almost 60–70 % of the FA was removed during the first 10 min of contact. Such rapid adsorption indicates that FA was accumulated onto corrosion sediments mainly due to physical-chemical interaction. The pseudo-second-order kinetics model was demonstrated to better describe the adsorption of FA onto corrosion sediments than the pseudo-first-order model. External mass transfer is the limiting stage of the process of FA adsorption onto corrosion sediments. This knowledge is useful for understanding of corrosion processes and biological regrowth in water supply pipes and thus further decrease of drinking water quality.

In indirect olfactometry analysis, to avoid condensation or adsorption processes during or storage of the sample, containers made of suitable materials should be used. Also, reaction between the chemicals during transport from the source of the odour to the research laboratory is an important process which can influence on examinations’ results. Study included determination of the odour and compound concentrations of six gas mixtures. Gas samples were collected by silicone hoses into Tedlar® bags and tested by Nasal Ranger, SM-100 olfactometers and Photovac Voyager gas chromatograph. Time of keeping gas in bags was 78 h, and concentration of compounds was measured every hour, eight times per day. For benzene, acetone, 1,1-dichloroethylene, c-1,2-dichloroethylene, t-1,2-dichloroethylene, methyl ethyl ketone and vinyl chloride, 100 % decrease of concentration has been noticed within 78 h of holding in the bag. Average rate of loss of most compounds concentration was from 0.01 to 2.50 % for the first 30 h and from 0.35 to 18.50 % during the last 48 h of examination. Decreasing of odour concentration measured by Nasal Ranger (NR) in all series was between 0.00 and 4.98 % till 30 h, between 1.91 and 100 % in the last 48 h of test and between 1.61 and 100 % in 78 h. In case of odour concentration measured by SM, those values were, respectively, 1.26–4.93 %, 1.39–4.93 % and 2.40–3.18 %. Values of average rate of intensity decreasing were, respectively, 0.77–1.75 %, 2.36–4.67 % and 1.18–2.07 %. Statistically significant correlation coefficients for compound concentrations and intensity, odour concentration obtained by SM-100 as well as NR were, respectively, 0.55–0.97, 0.47–0.99 and 0.37–0.98.

Dichlorodiphenyltrichloroethane (DDT) is one of the persistent organic pollutants (POPs) that are highly toxic to the environment. Effective evaluation on the bioavailability of DDTs in soils is essential for risk assessment and soil remediation. The aims of this study were to verify the feasibility of the hydroxypropyl-β-cyclodextrin (HPCD) extraction method for predicting the bioavailability of DDT, dichlorodiphenyldichloroethane (DDD), and dichlorodiphenyldichloroethylene (DDE) in soils, and to examine the effect of HPCD on their biodegradation in different soils. Four soils were aged with a mixture of p,p′-DDT, o,p′-DDT, p,p′-DDD and p,p′-DDE (0.25 μg g⁻¹ for each compound) for 20 and 100 days, respectively. For each of the DDTs, a significant positive correlation between HPCD-extractable fraction and biodegradable fraction in each soil was observed. It was demonstrated that the amounts of HPCD-extractable p,p′-DDT and o,p′-DDT were not significantly different from the amounts that were degradable as assessed from their degradation by Enterobacter sp. LY402 (p > 0.05). Such 1:1 relationship between extraction and degradation was not obtained in the cases of p,p′-DDD and p,p′-DDE, as the amounts of degradable p,p′-DDD and p,p′-DDE were lower than the amounts that were extractable with HPCD. Additionally, the biodegradation of p,p′-DDT, o,p′-DDT, p,p′-DDD, and p,p′-DDE was inhibited in the presence of HPCD, which could be due to the binding of the compounds to HPCD, making them less available to access the bacteria for degradation. This study provides the possibility of using the HPCD extraction method to predict the bioavailability of p,p′-DDT and o,p′-DDT in soils. But when HPCD was used as an additive in the bioremediation of DDT-contaminated soils, it might have a negative effect on biodegradation.

In the present work, the role of chemical compounds of one abundant vegetable waste, exhausted coffee, on Cr(VI), Cu(II), and Ni(II) sorption has been investigated. For this purpose, exhausted coffee was subjected to sequential extractions by using dichloromethane (DCM), ethanol (EtOH), water, and NaOH 1 %. The raw and treated biomass resulting from the extractions were used for metal ions sorption. Sorption results were discussed taking into consideration polarity and functional groups of raw and treated biomass. In general, the successive removal of extractives led to an insignificant increase in the studied metal ions sorption after DCM, EtOH, and water. The sorption results using free-extractive materials showed that metal sorption can be effectively achieved without this non-structural fraction of the sorbent. Alkaline hydrolysis destroyed in part the structural compounds of the sorbent resulting in an insignificant decrease of chromium removal while a significant increase of copper and nickel sorption was observed. The determination of elemental ratios of exhausted coffee and all treated biomass evidenced the involvement of oxygen functional groups in copper and nickel sorption. FTIR analysis confirmed the involvement of lignin moieties in the chromium sorption by exhausted coffee. As a final remark, this study shows that the sequential extraction opens new expectations to the total valorisation of lignocellulosic-based biomasses. The extractives can be removed and used as a biosource of valuable compounds, and the resulting waste can be used as a sorbent for metal ions keeping the same capacity for metal sorption as the non-extracted biomass.