The influents of plants treating complex industrial wastewaters from third parties may contain a large variety of often unknown or unidentified potentially harmful substances. The conventional approach of assessing and regulating the effluents of these plants is to set emission limit values for a limited set of physicochemical parameters, such as heavy metals, biological oxygen demand, chemical oxygen demand and adsorbable organic halogen compounds. The objective of this study was to evaluate the relevance of physicochemical parameters for setting emission limit values for such plants based on a comparison of effluent analyses by physicochemical and biological assessment tools. The results show that physicochemical parameters alone are not sufficient to evaluate the effectiveness of the water treatment plants for removing hazardous compounds and to protect the environment. The introduction of toxicity limits and limits for the total bioaccumulation potential should be considered to supplement generic parameters such as chemical oxygen demand and adsorbable organic halogens. A recommendation is made to include toxicity screening as a technique to consider in the determination of best available techniques (BAT) during the upcoming revision of the BAT reference document for the waste treatment industries to provide a more rational basis in decisions on additional treatment steps.

This study investigates the ability of Rhodococcus sp. strain p52, a dioxin degrader, to biodegrade petroleum hydrocarbons. Strain p52 can use linear alkanes (tetradecane, tetracosane, and dotriacontane), branched alkane (pristane), and aromatic hydrocarbons (naphthalene and phenanthrene) as sole carbon and energy sources. Specifically, the strain removes 85.7 % of tetradecane within 48 h at a degradation rate of 3.8 mg h⁻¹ g⁻¹dry cells, and 79.4 % of tetracosane, 66.4 % of dotriacontane, and 63.9 % of pristane within 9–11 days at degradation rates of 20.5, 14.7, and 20.3 mg day⁻¹ g⁻¹dry cells, respectively. Moreover, strain p52 consumes 100 % naphthalene and 55.3 % phenanthrene within 9–11 days at respective degradation rates of 16 and 12.9 mg day⁻¹ g⁻¹dry cells. Metabolites of the petroleum hydrocarbons by strain p52 were analyzed. Genes encoding alkane-hydroxylating enzymes, including cytochrome P450 (CYP450) enzyme (CYP185) and two alkane-1-monooxygenases, were amplified by polymerase chain reaction. The transcriptional activities of these genes in the presence of petroleum hydrocarbons were detected by reverse transcription-polymerase chain reaction. The results revealed potential of strain p52 to degrade petroleum hydrocarbons.

Regional material flows are strongly influenced by human diets. To diagnose and prevent environmental problems that threaten urban sustainability, the impact of human diet changes with rapid urbanization on the regional nitrogen (N) and phosphorus (P) flows were quantitatively evaluated. A survey of day-to-day activities was conducted of 450 individuals surveyed (adults over 18 years old) in three representative areas (the central district, the new district, and the suburban/rural areas) of Shanghai, a megacity which has attracted worldwide attention. The lifestyle (eating habits, domestic sanitation, drainage facilities, etc.) pattern was determined and the potential N and P loads from human diets on the environment were calculated. The daily potential nitrogen and phosphorus loads from human diets was 19.36 g-N, 1.80 g-P in the central district, 16.48 g-N, 1.52 g-P in the new district, and 13.04 g-N, 1.20 g-P in the suburban/rural areas of Shanghai. Respondents in all three areas, especially those in the suburban/rural areas reported a preference for increasing the intake of animal-derived as well as processed foods, which means that the potential N and P load from human diets to the environment will increase further. In addition, most respondents consider industrial wastewater discharge as the main cause of eutrophication of waterbodies, though in recent years water pollution caused by domestic wastewater has increased rapidly, but this has received much less attention. Environment-friendly eating habits and improvements in the environmental awareness will be required.

The phenomenon of coagulation settling in liquid suspensions has a variety of applications, including mineral processing, treatment of industrial effluents, and municipal sewage sludge purification. This study was to investigate the coagulation settling characteristics of fine-grind natural zeolite and evaluate the removal efficiency of contaminants simultaneously in static and turbulent flow. A series of column experiments were conducted to pattern the characteristics of spatial and temporal variation of coagulation settling and removal contaminants in static and turbulent flow. The results indicated that the suspended solid concentration presented an apparent exponential decay with coagulation settling time in static flow (R ² > 0.99), coagulation settling rate of the fine zeolite-suspended solid in static flow was between 0.005 and 0.05 cm/s obtained from the repeat depth suction method. The relation between average C/C ₀ of pollutants and suspended solid concentration was exponential before the settlement for 24 h and that was the line after the settlement for 24 h. Several various models were presented to highlight the coagulation settling characteristics of fine-grind natural zeolite in static and turbulent flow. Compared to hydrostatic settling experiments, zeolite-suspended solid presented better removal efficiency of pollutants and greater removal rate of pollutants in turbulent flow.

Microorganisms play an indispensable role in the ecological functioning of marine environment. Some species are sensitive while others are insensitive for a specific pollutant. The aim of this work is a preliminary study of the quantitative and qualitative distribution of cultivable vibrios in sediments and water samples characterized by different toxicity levels. For 1 year, in three suitably selected sampling stations of Mar Piccolo in Taranto (Ionian Sea, Italy), we have evaluated the toxicity level by Microtox® system, vibrios, total, and fecal coliform densities. The results of the Microtox® tests showed sediments characterized by an elevated level of toxicity, while the interstitial water of the same sites always showed biostimulatory phenomenon. The quantitative results show that vibrios and coliforms are more abundant in water than in sediment samples. The most often isolated strains were: Vibrio alginolyticus, Vibrio mediterranei, Vibrio metschinkovii, and Vibrio splendidus II. This work is the first example of study on the distribution of Vibrio species related to toxicity evaluation conducted by the Microtox® bioassay. The results show the different distribution of Vibrionaceae in two environmental matrices analyzed and characterized by different levels of toxicity.

2,4,7,9-tetramethyl-5-decyne-4,7-diol (TMDD) is a high-production volume chemical used in paper, ink, pesticide, and adhesive industries as a wetting and anti-foaming agent. The physicochemical properties and slow biodegradation rate of TMDD indicate a low bioaccumulation potential but a high prevalence in the environment. As a consequence, TMDD has been detected in several European rivers in the nanogram per liter and lower microgram per liter range; however, its environmental risk to aquatic organisms is considered low. Recent studies almost exclusively focused on acute effects by TMDD, little is known about cytotoxic and genotoxic effects, reproduction and developmental toxicity, endocrine disruption, and any kind of long-term toxicity and carcinogenicity so far. The present study aims to provide more specific baseline information on the ecotoxicological effects of TMDD in fish. For this end, cyto- and genotoxicity assays were carried out in vitro with the permanent fish cell line RTL-W1; in addition, in vivo studies were conducted with the early life stages of zebrafish (Danio rerio) in order to fill the data gaps in developmental toxicity and endocrine disruption. TMDD showed a cytotoxic and slight genotoxic potential in fish cell lines; moreover, various sublethal and lethal effects could be detected in developing zebrafish embryos. There was no evidence of endocrine-disrupting effects by TMDD; however, mortality following prolonged exposure to TMDD during fish sexual development test was clearly higher than mortality in the fish embryo test after 96-h exposure. Our results thus confirmed previous findings of laboratory screening tests, suggesting short-term toxic effects of TMDD in the intermediate, and long-term effects in the lower milligram per liter range.

The endophytic bacterium isolated from Scirpus triqueter was proved to be an oil-degraded bacterium. A pot experiment was conducted to investigate the removal ratio of diesel under the combined effect of oil-degraded microorganism (Pseudomonas sp. J4AJ) and S. triqueter. The effect of diesel on plant growth parameters, soil enzymes and microbial community was assessed after 60 days. The results showed that the soils which were planted with S. triqueter and inoculated with J4AJ displayed the highest removal ratio (54.51 ± 0.15 %) after 60-day experiment. However, the removal ratio of J4AJ-treated soils was 38.97 ± 0.55 %. Diesel was toxic to S. triqueter, as evidenced by growth inhibition during the experimental period. However, the plant height and stem biomass in the soils inoculated with J4AJ significantly increased. The combined effect of S. triqueter and J4AJ improved the enzyme activities of the catalase and dehydrogenase in the contaminated soil. The diversity index in soils under the effect of S. triqueter combined with J4AJ was lower than that of the other soil samples. The principal analysis of phospholipid fatty acid signatures revealed that the combined effect of S. triqueter and J4AJ increased the differences of soil microbial community structure with the other treatments.

In this study, we investigated whether ammonia emissions from industrial composting of organic waste may influence the surrounding environment, using lichens as bioindicators. To this purpose, samples of N-tolerant and N-sensitive lichens, namely Xanthoria parietina and Evernia prunastri, were transplanted for 1–3 months along transects at increasing distance (0–400 m) from a composting facility in Tuscany, Italy. Atmospheric concentrations of ammonia were measured using passive samplers. The physiological response of lichen transplants was investigated by means of the photosynthetic efficiency (measured as chlorophyll a fluorescence emission), the integrity of cell membranes (measured as electrolyte leakage), and sample viability (measured as enzymatic activity of dehydrogenase). Epiphytic lichen communities were investigated using biodiversity indices. The results showed decreasing concentrations of ammonia, from 48.7 μg/m³at the composting facility to 2.7 μg/m³at 400 m. The N-tolerant X. parietina was not affected and some physiological parameters even showed a higher performance, while the N-sensitive E. prunastri showed a reduced performance with increasing atmospheric concentrations approaching the source. A shift from lichen communities composed by meso-acidophilous species (actual condition) to more nitrophilous communities in the near future, approaching the composting facility is suggested. It is concluded that lichens can provide useful data for decision-makers to establish correct science-based environmentally sustainable waste management policies.

This study reports the chemical fractionation of several potentially toxic elements (Zn, Pb, Cd, As, and Sb) in contaminated technosoils of two former smelting and mining areas using two sequential extraction schemes. The extraction schemes used in this study were the Tessier’s scheme and a modified BCR scheme. The fractions were rearranged into four equivalent fractions defined as acid soluble, reducible, oxidizable, and residual to compare the results obtained from two sequential extraction schemes. Surface soils were samples from a waste landfill contaminated with Zn, Pb, and Cd located at Mortagne-du-Nord (MDN; North France) and from a settling basin contaminated with PTE such as As, Pb, and Sb located at La Petite Faye (LPF; Limoges, France). The study of the Zn, Pb, Cd, As, and Sb partitioning in the acid soluble, reducible, oxidizable, and residual fractions of the technosoils revealed that Zn, Cd, and Pb were mainly associated with the acid soluble and reducible fractions for MDN site, while As, Sb, and Pb were associated with residual fraction for LPF site. Fractionation results indicate that the percentages of Zn, Pb, Cd, As, and Sb extracted in Fe–Mn oxide bound fraction of Tessier’s scheme were always higher than those extracted by modified BCR scheme. This may be attributed to the stronger Tessier’s scheme conditions used to extract this fraction. In contrast the percentages of Zn, Pb, Cd, As, and Sb extracted in the organic fraction of the modified BCR scheme were always higher than those of the Tessier’s scheme. The order of mobility of PTE was as follows: Cd > Zn > Pb in MDN site and As > Sb > Pb in LPF site. PTE were distributed in all soil fractions, with the most relevant enrichments in extractable and residual fractions. A significant amount of Cd, Pb, and Zn were rather mobile, which suggests that these elements can be readily available to plants and soil organisms.

A Fenton oxidation system employing zero-valent iron (whose source was swarf, a residue of metallurgical industries, in powder form) and hydrogen peroxide for the treatment of an aqueous solution with six pesticides was developed, and the effect of the iron metal content, pH, and hydrogen peroxide concentration was evaluated. The characterization of the aqueous solution resulted in: pH 5.6, 105 mg L⁻¹of dissolved organic carbon, and 44.6 NTU turbidity. In addition, the characterization of the swarf by FAAS and ICP-MS showed 98.43 ± 7.40 % of zero-valent iron. The removal was strongly affected by the content of iron metal, pH, and hydrogen peroxide concentration. The best degradation conditions were 2.0 g swarf, pH 2.0, and 5 mmol L⁻¹H₂O₂. At the end of the treatment, the pesticide degradation ranged from 60 to 100 %, leading to 55 % mineralization. Besides, all hydrogen peroxide was consumed and the determination of total dissolved iron resulted in 2 mg L⁻¹. Thus, the advantages of this system are rapid degradation (up to 20 min), high-degradation rates, simple handling, and low cost.