Activated carbon fiber-supported cobalt phthalocyanine photocatalyst (Co-TDTAPc-F) was prepared in this study, and its performance for dye wastewater decoloration was investigated, and Acid Orange II (AO7) was selected as the target pollutant. The morphology analysis of Co-TDTAPc-F was conducted, and the effects of catalyst loading, H₂O₂ addition, solution pH, and catalyst reuse on AO7 decoloration efficiency were evaluated. The results showed that AO7 decoloration efficiency increased by 23.2% during the Co-TDTAPc-F photocatalytic process as compared with solely Co-TDTAPc-F adsorption, and the decoloration process was fitted by pseudo first-order reaction. The increase of catalyst loading and H₂O₂ content both benefitted AO7 decoloration. Strong photocatalytic activities were observed at both acidic and alkaline conditions; however, total organic carbon (TOC) removal efficiency decreased with the increase of solution pH. Strong photocatalytic activity was still observed after four times reuse. The mechanisms of AO7 photocatalytic decomposition by Co-TDTAPc-F were proposed.

The surface morphology of biocathode was one of the limiting factors for microbial fuel cell (MFC) design. Up-flow membrane-less single-chambered MFC (UFML MFC) was used to investigate the effect of surface morphology of carbon material as aqueous biocathode. Pt-loaded carbon paper, carbon felt, and carbon plate were examined and compared on the power output, surface morphology for biofilm formation, Coulombic efficiency (CE), and chemical oxygen demand (COD) reduction. The COD reduction was up to 90 % in UFML MFC with Pt-loaded carbon paper, carbon felt, and carbon plate as aqueous biocathodes. The results obtained showed that the performance in voltage output was not related to internal resistance but mainly due to the ability of cathode material in oxygen reduction process. The performance of voltage output with different materials as aqueous biocathode was mainly based on to the surface morphology as it was related to the ability of biofilm formation. Roughness of aqueous biocathode’s surface morphology could prompt the biofilm growth, while biofilm overgrowth on aqueous biocathode could decrease voltage output. Therefore, smoother surface morphology of aqueous biocathode is more suitable for long-term operation.

Mercury (Hg), aside from having high toxicity, is characterized by its ability to biomagnify in the marine trophic chain. This is an important problem especially in estuaries, or in the coastal zone, particularly near the mouths of large rivers. This study was conducted in the years 2001–2011, in the coastal zone of the Baltic Sea near to the mouth of the River Vistula, which is the second biggest river discharging into the Baltic. Mercury concentration was measured in the tissues and organs of cod, flounder, herring, seals (living in the wild and in captivity), great black-backed gulls, and African penguins from Gdańsk Zoo, and also in human hair. Penguins and seals at the seal sanctuary in Hel were fed only herring. In marine birds and mammals and in the pelagic herring, the highest Hg concentration was observed in the kidney and in the liver, while in cod and flounder (located on a higher trophic level) the muscles were the most contaminated with mercury. In gray seals living in the seal sanctuary, Hg concentration in all analyzed tissues and organs except the kidneys was lower in comparison with seals living in the wild. The comparatively small share of fish in the diet of local Polish people and their preference towards the consumption of herring contributed to low concentration of Hg in their hair. The protective mechanisms related to detoxification and elimination of mercury were shown to be more effective in the seals than in the penguins, despite the former consuming around 10 times more food per day.

The overall purpose of this work was to evaluate the treatment system performance of sequential hybrid bioreactors, one without aeration and another with intermittent aeration, in the bioremoval of Cr(VI) and total chromium and in the removal of total organic carbon (TOC). The saturation kinetic curves were studied with initial concentrations of Cr(VI) of 80, 120 and 150 mg L⁻¹. A reference test was performed before adding chromium to the system, with the intention of checking the influence of the presence of chromium on the TOC removal. During the bioreactor regeneration, the chromium removal was evaluated, after each kinetic studied. For kinetics with 80 mg L⁻¹ of Cr(VI), the results showed that after 600 h of operation, there was no saturation of bioreactors, yielding 87 % overall removal of Cr(VI) and 62 % chromium total. For initial concentrations of Cr(VI) of 120 and 150 mg L⁻¹, only the non-aerated bioreactor reached saturation after 228 and 216 h of operation, respectively. In regeneration, it was found in all the assays performed that the chromium concentration at the outlet of the bioreactor became almost zero at a maximum of 72 h of operation. In the blank test, the TOC removal achieved was 64 %, while in the three tests in the presence of chromium, this was approximately 55 % (80 mg L⁻¹), 41 % (120 mg L⁻¹) and 31 % (150 mg L⁻¹). After cell lysis by ultrasound, it was found that the chromium concentration retained inside there was lower than the concentrations present in the environment.

This study evaluated the effects of abattoir wastewater irrigation on plant growth and development. The soils used in this study were collected from Primo Smallgoods Abattoir (Port Wakefield, South Australia) at different sites such as currently irrigated (CI), currently not irrigated (CNI) and soil outside the irrigation area as control (CTRL). A completely randomised block design was employed for the plant growth experiment, where four crops (Pennisetum purpureum, Medicago sativa, Sinapis alba and Helianthus annuus) were grown separately on three different soils (CI, CNI and CTRL) in plastic pots. Two types of water (tap water and wastewater) and two loadings were applied throughout the planting period based on the field capacity (FC 100 and 150 %). The overall dry matter yield was compared between the soils and treatments. Under wastewater irrigation, among the four species grown in the CI soil, P. purpureum (171 g) and H. annuus (151 g) showed high biomass yields, followed by S. alba (115 g) and M. sativa (31 g). The plants grown under tap water showed about 70 % lower yields compared to the abattoir wastewater irrigation (AWW). Similar trends in the biomass yields were observed for CNI and CTRL soils under the two water treatments, with the biomass yields in the following order CI > CNI > CTRL soils. The results confirm the beneficial effects of AWW at the greenhouse level. However, a proper cropping pattern and wastewater irrigation management plan is essential to utilise the nutrients available in the wastewater-irrigated land treatment sites. The increase in fertility is evident from the effects of wastewater on biomass growth and also the abundance of nutrients accumulated in plants. A mass balance calculation on the applied, residual and the plant-accumulated nutrients over a few cropping periods will help us in understanding the nutrient cycling processes involved in the abattoir-irrigated land treatment sites, which will serve as an effective tool for the environmental management.

Diazinon is an extensively applied organophosphate pesticide, and nonylphenol is one of the major degradation products of nonylphenol polyethoxylates which are commonly used as surfactant in pesticide formulations. Both pollutants are widely distributed and often coexist in agroecosystems, where they might cause toxic effects to wild biota. This study assessed single and joint toxicity of binary mixtures of these organic compounds on the early development of Rhinella arenarum by means of a standardized test. Joint toxicity of diazinon/nonylphenol mixtures were assessed in embryos and larvae exposed to three different proportions at different exposure times. Embryo and larval toxicity was time-dependent, and larvae were significantly more sensitive than embryos to both compounds. For both embryos and larvae, nonylphenol was between 11 and 18 times more toxic than diazinon. Joint toxicity of the chemicals showed a tendency to be significantly higher than the predicted by additivity effects highlighting the threat that diazinon/nonylphenol mixtures represent for Rhinella arenarum populations.

High amounts of antibiotics are introduced in the soil environment by manure amendment, which is the most important spreading route in soil, with a potential ecotoxicological impact on the environment. The objectives of this study were (a) to assess the tetracycline (Tc) bioavailability in a clay and in a sandy soil, and (b) to evaluate the effects of the Tc and cow manure on the structure and function of soil microbial communities. Clay and sandy soils were spiked with Tc at the concentrations of 100 and 500 mg Tc kg⁻¹ soil, and were amended or not with cow manure. The clay soil showed greater Tc sorption capacity and bioavailable Tc was between 0.157 and 4.602 mg kg⁻¹ soil. Tc dose and time-dependent effects on soil microbial communities were investigated by fluorescein diacetate activity, phospholipid fatty acids analysis, as well as by Biolog community level physiological profile and microbial counts at 2, 7 and 60 days after Tc and/or manure addition. The added Tc caused detrimental effect on the microbial activity and structure, particularly in the short term at the highest concentrations. However, the Tc effect was transient‚ it decreased after 7 days and totally disappeared within 60 days. Cow manure shifted the bacterial structure in both soils, increased the microbial activity in clay soil and contributed to recover the microbial structure in Tc-spiked manure treatments.

Adsorption of the herbicide glyphosate and its main metabolite AMPA (aminomethylphosphonic acid) was investigated on 17 different agricultural soils. Batch equilibration adsorption data are shown by Freundlich adsorption isotherms. Glyphosate adsorption is clearly affected by equilibration concentrations, but the nonlinear AMPA adsorption isotherms indicate saturation of the adsorption sites with increasing equilibrium concentrations. pHCₐCₗ₂ (i.e. experimental pH) is the major parameter governing glyphosate and AMPA adsorption in soils. However, considering pHCₐCₗ₂ values, available phosphate amount, and amorphous iron and aluminium oxide contents by using a nonlinear multiple regression equation, obtains the most accurate and powerful pedotransfer rule for predicting the adsorption constants for these two molecules. As amorphous iron and aluminium oxide contents in soil are not systematically determined, we also propose a pedotransfer rule with two variables—pHCₐCₗ₂ values and available phosphate amount—that remains acceptable for both molecules. Moreover, the use of the commonly measured pHwₐₜₑᵣ or pHKCₗ values gives less accurate results compared to pHCₐCₗ₂ measurements. To our knowledge, this study is the first AMPA adsorption characterization for a significant number of temperate climate soils.

Natural organic matter (NOM) in groundwater is a factor of concern in long-term operation of Fe⁰ permeable reactive barrier (PRB). In this study, humic acid, a major component of NOM, showed dual effects in trichloroethylene (TCE) removal from simulated groundwater by Fe⁰ in batch and column experiments. In the initial stage of contacting with Fe⁰, humic acid promoted TCE removal due to its hydrophobic partitioning towards TCE and the subsequent fast adsorption onto Fe⁰ surfaces. In a long run, humic acid inhibited TCE removal because the buildup of adsorbed humic acid on Fe⁰ surfaces passivated Fe⁰ reactivity and limited TCE mass transfer. Ca²⁺ enhanced the co-aggregation of humic acid with Fe⁰ corrosion products and led to a faster depletion of TCE removal capacity by diminishing Fe⁰ matrix porosity. Revealed by FTIR analysis, part of TCE removed through hydrophobic partitioning was retained in humic acid accumulated on Fe⁰ surfaces rather than reductively degraded by Fe⁰. It raises a concern of using Fe⁰ PRB to treat organic contaminants in NOM-rich groundwater. Releasing back of NOM retained organic contaminants might take place once the accumulated NOM is desorbed or detached from Fe⁰ surfaces, resulting in a rebound of organic contaminants in the groundwater beyond the confine of PRB.

Agricultural practices are the main source of water contamination in rural areas. Rainfall events, and subsequently, soil leaching and storm runoff are mainly controlling the transfer of pollutants from diffuse sources in watersheds during floods. These periods are also very important to better understand their dynamics, particularly their different soil-river transfer pathways (surface runoff SR, subsurface runoff SSR, and groundwater flow GF). This study focuses on riverine transfers of both pesticides and trace elements. High-resolution monitoring of water discharge and water sampling were performed during a flood event that occured in May 2010 in an agricultural catchment of SW France. Chemical composition of major and trace elements, silica, alkalinity, pH and conductivity, DOC and POC, TSM, and commonly used pesticides were analyzed with a high sampling frequency. The different stream flow components (SR, SSR, and GF) were assessed using two independent hydrograph separation methods: a hydrological approach based on Maillet’s formula (1905) for the recession period and a chemical approach based on physico-chemical tracers, TSM for SR and PO₄³⁻ for GF. Both methods exhibited important contributions of SR (33 %) and SSR (40 %) to the total riverine pollutant transfers. The contribution of different components was also visible using concentration-discharge relationships which exhibited hysteresis phenomenon between the rising and the falling limbs of the hydrograph. Higher concentrations during the rising period (clockwise hysteresis) were characteristic of pollutants mainly exported by SR (trifluralin, Cd). Anticlockwise hysteresis with higher concentration during the recession period showed pollutants mainly exported by SSR (metolachlor, Cu). Moreover, significant relationships were highlighted between the controlling factors (DOC, POC, and TSM) and SR, SSR, and GF contributions: DOC and the complexed pollutants were highly correlated to SSR while POC, TSM, and the adsorbed pollutants were linked to SR. During the flood, K d of most pollutants increased, particularly at the beginning, and therefore, future studies should investigate their availability to living organisms and thus their toxicity. An additional characteristic equation between K d and K ₒw of the different pesticides was proposed to help future management, modelling, and estimation of pollutant transfers during floods.