This paper presents for the first time the technological potential of novel Lantana camara-reinforced ethylene vinyl acetate (EVA) composites fabricated via the melt-blending technique. The composite and L. camara were characterized using X-ray diffraction spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis and deferential scanning calorimeter. L. camara was found to drastically reduce the crystallinity of EVA from 44.3 % to a minimum of 1.16 %. Immersion of the composite specimens in de-ionised water showed that moisture absorption was less significant for composites with L. camara contents less than 15 % (w/w). A maximum sorption capacity of 1.20 mol% was recorded in 42 h which is remarkable considering the hydrophobic nature of EVA with 9 % vinyl acetate. L. camara and the composite removed 96 % and 88 % para-nitrophenol from water, respectively.

Fluorescence in situ hybridization (FISH) technique and qPCR analyses, targeting atz genes, were applied to detect the presence of simazine-degrading bacteria in an agricultural soil with a history of herbicide application. atzB-targeted bacteria detected by FISH represented 5% of total soil bacteria with potential capability to metabolize the herbicide. The soil natural attenuation capacity was confirmed in soil microcosms by measuring simazine degradation. Moreover, four bacterial strains were isolated from the soil and identified as Acinetobacter lwoffii, Pseudomonas putida, Rhizobium sp. and Pseudomonas sp. The isolates were able to grow using different s-triazine compounds and related metabolites as the sole carbon source. Growth parameters in presence of simazine were calculated using the Gompertz model. Rhizobium sp. showed the highest simazine degradation (71.2%) and mineralization (38.7%) rates, whereas the lowest values were found to A. lwoffii—50.4% of degradation and 22.4% of mineralization. Results from qPCR analyses of atzA, atzB and atzC genes revealed their presence in Rhizobium sp. and A. lwoffii, being atzB and atzC the most abundant functional genes. Rhizobium sp. showed a higher amount of the three biomarkers compared to A. lwoffii: the atzA, atzB and atzC gene copy number per microlitre were, respectively, 101, 102 and 103-fold higher in the former. Therefore the proposed molecular approaches based on the use of atz genes as biomarkers can be considered as useful tools to evaluate the presence and potential capability of degrading-s-triazines soil microorganisms.

Comparison of event-based precipitation collected during 1 year showed that samples from a Yankee Environmental Systems collector had significantly higher volume, higher concentrations, and higher deposition of all ions analyzed except PO 4 3− and NH 4 + compared to samples collected simultaneously with an Aerochem Metrics collector.

Chestnut agro-industrial companies consume a high volume of water for washing and processing fruit, generating a large volume of wastewater. This work studied the biodegradation of chestnut processing wastewater through aerobic assays, varying substrate, and biomass concentrations. In general, this wastewater presents a good biodegradability, especially in experiments with relatively low chemical oxygen demand (COD) (0.4 and 0.6 g O₂ L⁻¹) allowing a COD removal of 85–90 %. The best results were obtained in the reactor initially loaded with 2 g L⁻¹ of biomass and 0.4 or 0.6 g O₂ L⁻¹ of COD. These experiments also showed high COD removal rates: 4.25 and 3.88 g COD g⁻¹ volatile suspended solids (VSS) h⁻¹, respectively. The sedimentation rate, evaluated for different initial values of biomass (1, 2, and 3 g L⁻¹), always presented higher values in the experiments with 2 and 3 g L⁻¹ of biomass, regardless of the initial COD value used. After comparing different kinetic models (Monod, Contois, and Haldane), it was observed that the Haldane inhibition model satisfactorily describes the COD biodegradation. AQUASIM software allowed calculating the kinetic constant ranges: K ₛ, 1.59–6.99 g COD L⁻¹; ν ₘₐₓ, 25–40 g COD g⁻¹ VSS day⁻¹; and K ᵢ values, 0.07–0.11. These kinetic constants corresponds to maximum rates (ν*) between 1.48 and 4.25 g COD g⁻¹ VSS day⁻¹ for substrate concentrations (S*) from 0.38 to 0.88 g COD L⁻¹.

High As groundwater normally contained high concentrations of Cl⁻ and HCO ₃ ⁻ . This study examined the effects of Cl⁻, HCO ₃ ⁻ , and As species on As uptake by hyperaccumulator Pteris vittata. Plants were exposed hydroponically to 5.0 mg/L As(III) or As(V) in the presence of 0, 0.5, 1, 2, 5, 10, and 20 mM of Cl⁻ or HCO ₃ ⁻ for 10 days. Addition of high Cl⁻ concentrations (>10 mM) slightly inhibited P. vittata growth (biomass), while generally had no significant effect on plant As uptake. High solution pH resulted in reduced plant growth and As uptake, which attributed to the inhibitory effects in HCO ₃ ⁻ treatments with the high pH of the high HCO ₃ ⁻ concentration. It was speculated that addition of HCO ₃ ⁻ (<20 mM) would have no significant effect on plant growth and As uptake. The inhibitory effect of HCO ₃ ⁻ on As translocation was less apparent in the As(III) solutions than the As(V) solutions. For the high As groundwater with As(III) as the predominant species, high pH, instead of high concentrations HCO ₃ ⁻ and Cl⁻, was expected to inhibit As uptake. The results suggested that optimum plant growth and maximum As hyperaccumulation could be achieved by adjusting solution pH in the growth media (around 7.2).

Over a century of metal processing activity has resulted in widespread metal contamination of soils in Sudbury, ON, Canada. To assess the potential for recovery from the large reductions in metal deposition, critical loads were estimated for metals at 415 sites in Sudbury using an ‘effects based’ approach that is based on exceedance of provincial soil guidelines using multiple independent estimates of metal partitioning (Kd) for each metal. Sudbury soils are heavily contaminated with copper (Cu) and nickel (Ni), with 74 % of samples currently exceeding the provincial soil guideline for Cu and 87 % of samples exceeding the guideline for Ni. Both metals are strongly correlated with other metals (zinc (Zn), cadmium (Cd), lead (Pb)), although they rarely exceed provincial guidelines Copper and Ni are also strongly correlated with organic matter but not soil pH. Based on the most recent Cu and Ni deposition estimates (mid-1990s), it is estimated that between 20 % and 51 % of the sites receive deposition in excess of the ‘effects based’ critical load for Cu and between 5 % and 97 % of sites receive atmospheric deposition in excess of the ‘effects based’ critical load for Ni. These results suggest that Cu and Ni concentrations in soil will generally decrease resulting in slightly fewer sites that exceed the provincial soil guideline, but that the timeframe of this response will be very slow, with relatively little change occurring over the next 100 years. Even assuming a best case deposition scenario whereby Cu and Ni deposition were to immediately fall to background levels, the percentage of sites with Cu and Ni levels in excess of the OMOE guideline would still be between 69 % and 72 %, and 56 % and 86 %, respectively, demonstrating that while recovery of the Sudbury soils is possible, greater reductions in metal deposition are needed and even so, it will be a process that takes several centuries.

Contact time, pH, fluoride concentration, and sorbent dose effects on the removal of fluoride ions by a carbonaceous material obtained from pyrolysis of sewage sludge (CM) were evaluated. Equilibrium was reached after 18 h of contact time and the maximum sorption was found at pHeq = 7.06 ± 0.08, which corresponds to the zero charge point of the CM. The highest efficiency in the sorption system for fluoride removal (2.84 ± 0.03 mg F− [Formula: see text]) was found with 0.4 gCM L−1 and with 20 gCM L−1, 82.2 ± 0.5% of fluoride was removed. The kinetic data of the process could be fitted to the pseudosecond order and the intraparticle mass transfer diffusion models, whereas isotherm to the Langmuir–Freundlich equation. These results indicate that the mechanism is chemisorption on a heterogeneous material. Fluoride ions were best partially desorbed using a bicarbonate ions solution and the material was partially regenerated by using a solution of HCl (pH = 1).

Low impact development (LID) is a land development strategy for managing stormwater at the source with decentralized micro-scale control measures. Since the emergence of LID practices, they have been successfully used to manage stormwater runoff, improve water quality, and protect the environment. However, discussions still surround the effectiveness of many of these practices, resulting in a reluctance to widely adopt them. This paper highlights evidence in the literature regarding the beneficial uses of LID practices. A discussion of how LID practices are represented in hydrologic/water quality models is also provided using illustrative examples of three computational models developed with algorithms and modules to support widespread adoption of LID practices. Finally, the paper suggests directions for future research opportunities.

Polybrominated diphenyl ethers (PBDEs) are highly persistent anthropogenic contaminants found in trace amounts in many environmental compartments far from their source areas, posing a risk to aquatic ecosystems. Our objective was to determine the relative toxicities of three BDEs, BDE-47, BDE-99 and BDE-154 on marine phytoplankton algae Isochrysis galbana. For a highly sensitive endpoint: the 72-h inhibition of autotrophic growth rate was calculated according to standards methods. Actual PBDE concentration was measured by GC-MS and toxicity parameters were calculated on the basis of time-weighted mean actual concentrations. No observable effect concentration (NOEC) values were 2.53 μg L⁻¹ for BDE-47, 3.48 μg L⁻¹ for BDE-99 and 12.3 μg L⁻¹ for BDE-154, and LOEC values were 5.06, 6.96 and 24.60 μg L⁻¹ for BDE-47, BDE-99 and BDE-154, respectively. The calculated IC₁₀ (the concentration inhibiting growth rate by 10 %) corresponded to 9.3, 12.78 and 54.6 μg L⁻¹ for BDE-47, BDE-99 and BDE-154, respectively. The 50 % inhibitions of growth rate (IC₅₀) values were: 25.7 μg L⁻¹ BDE-47, 30.0 μg L⁻¹ BDE-99 and 243.7 μg L⁻¹ BDE-154. Therefore, the acute toxicity of PBDEs decreases as the degree of bromination increases, the order of toxicity is BDE-47 > BDE-99 > BDE-154. Significant (p < 0.05) adverse effects were observed for all compounds at concentrations >15 μg L⁻¹. Our results indicated that under laboratory conditions PBDEs inhibited the growth of marine phytoplankton at concentrations near 10 μg L⁻¹. However, further work is required to investigate long-term effects in these and other aquatic organisms.

In domestic wastewater, bacterial physiology controls cell production (growth, replication) and cell maintenance, determining how energy is allocated between these two processes. The aim here was to develop a method to quantify these cellular processes so that the bacterial physiological state could be manipulated to lower this source of pollution. We simultaneously used the incorporation of radiolabelled thymidine into DNA (a measure of new cell synthesis) and leucine into protein in wastewater to quantitatively distinguish bacterial growth from maintenance processes. We found that DNA and protein syntheses were coupled in wastewater after substrate enrichment (with glucose or acetate)—balanced growth. Once the substrate was depleted, the two processes became uncoupled—unbalanced growth. In this physiological state, the bacteria were synthesising protein, but fewer bacteria were replicating. More energy was allocated to cell maintenance than replication. A mean Leu/TdR ratio of 7.4 was determined for wastewater and was similar to natural aquatic ecosystems. As the bacterial growth rate decreased, the Leu/TdR ratios increased. We show how the simultaneous measurement of [³H]Leu and [³H]TdR quantitatively distinguishes balanced from unbalanced growth. Low [³H]Leu/[³H]TdR ratios indicated bacteria were physiologically stressed, an ideal state for biological wastewater treatment processes (WWTP) as the bacteria divert more energy to maintenance activities instead of growth. Leu/TdR ratios of 70 have been recorded in natural aquatic ecosystems which suggests WWTP have potential to be manipulated to achieve much higher Leu/TdR ratios than we report here. Changes to plant operation to improve operation efficiency include finding the optimum rate of substrate (pollution supply) or alternating aerobic and anaerobic periods to maximise the Leu/TdR ratio to achieve less biomass production for land disposal and more cost-effective operation that generates less pollution in the effluent.