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A quick, easy, cheap, effective, rugged and safe (QuEChERS) method was optimized for the extraction of non-steroidal anti-inflammatory drugs (NSAIDs) diclofenac and ibuprofen from sewage sludge. Dispersive-solid phase extraction (d-SPE) was employed for sample clean-up. Instrumental analysis was performed by high-performance liquid chromatography. Ecological risk was assessed for four trophic levels: fish, daphnia, algae and bacteria. The method limits of quantification for diclofenac and ibuprofen were 0.43 µg g− 1 and 0.45 µg g− 1, respectively. Correlation coefficients were above 0.999. Extraction recoveries ranged from 70 to 118 % and satisfactory inter-day reproducibility (% RSD) of < 18 % was obtained. Diclofenac and ibuprofen were measured up to 1.02 µg g− 1 and 6.6 µg g− 1, respectively in sewage sludge from three Nigerian wastewater treatment plants (WWTPs). Ibuprofen posed high risk to fish, daphnia, algae and bacteria. This work presents the first report on the ecological risk assessment of diclofenac and ibuprofen in sewage sludge from Nigerian WWTPs. [ABSTRACT FROM AUTHOR]

Biochar was prepared by mixing sewage sludge with sawdust via a co-pyrolysis with different mixture ratios and temperatures. The results showed that the sawdust addition resulted in a lower yield of biochar with higher C content. The total concentrations of Pb and Cd in biochar were reduced. Besides, pyrolysis can transform the potentially toxic Pb and Cd to stable fractions. However the sawdust addition had slight influence on the chemical forms of Pb and Cd in the biochar. The biochar with 50% sawdust at 600°C exhibited a remarkable reduction of the leachable metal concentrations. The possible transformation mechanisms of Pb and Cd were inferred as the formation of aluminum and silicon-containing minerals. These results provide insights into the influence of sawdust addition on the characteristics of biochar and the possible Pb and Cd immobilization mechanisms during co-pyrolysis process. [ABSTRACT FROM AUTHOR]

This study was carried out to develop mathematical regression equations for predicting the uptake of ten heavy metals (HMs) (cadmium, Cd; cobalt, Co; chromium, Cr; copper, Cu; iron, Fe; manganese, Mn; molybdenum, Mo; nickel, Ni; lead, Pb; zinc, Zn) by a vegetable species (Eruca sativa Mill.) in the Abha region (Saudi Arabia) based on the concentration of these HMs in soils amended with sewage sludge, organic matter (OM) content and soil pH. The resultant regression equations indicated that the three soil factors were significant predictors for the uptake of the ten HMs in the plant tissues. By applying a t test, we found that there are no significant differences between the actual and predicted values of the ten HMs in the E. sativa roots and leaves (P > 0.05), which reflects the goodness of fit of these equations for predicting the uptake of these HMs. Such types of equations may be helpful for evaluating the risk of cultivation of E. sativa plants in soils amended with sewage sludge. [ABSTRACT FROM AUTHOR]

In the present study, biochar particles (BPs) produced by the co-pyrolysis of sewage sludge and corncobs at temperatures of 300, 500, and 700°C were characterized. The Pb2+ adsorption properties and the heavy metal leaching toxicity rates of the BPs were investigated. It was found that the adsorption kinetics of the Pb2+ can be accurately described by a pseudo-second-order model, and the equilibrium adsorption data were well represented by both the Langmuir and the Freundilich Equations. The toxicity characteristic leaching procedure (TCLP) results indicated that the leaching concentrations of all the heavy metals were below the set limit of China's national standard (Identification Standard for Hazardous Waste Extraction Toxicity Identification, China National Standard, GB 5085.3-2007). The results of this study can successfully provide scientific support for future corncob treatment and sludge pollution control. [ABSTRACT FROM AUTHOR]

Wide occurrence of mercury species, including the highly toxic and readily bioaccumulative methylmercury (MeHg), in municipal sewage (MS) and sewage sludge (SS) has been evidenced in recent studies. Considering that vast amounts of MS and SS are produced globally each year and the majority of MS is discharged into aqueous environments, i.e., the main sites for MeHg bioaccumulation, special attention should be paid on the source and environmental behaviors of sewage-borne and sludge-borne mercury species. This review aims to summarize the findings on the occurrence of mercury species in MS and SS, their transport and transformation in MS treatment plants, as well as their fate and environmental implications. [ABSTRACT FROM AUTHOR]

The paper attempts at evaluating potential for the use of sewage sludge produced in a rural area for the rehabilitation of ground degraded by the sodium processing industry. The results demonstrated that the studied sewage sludge conforms to the current regulatory standards, enabling its use in land rehabilitation, both for agricultural and non-agricultural purposes. Ground in areas degraded by the KZS "Solvay" industrial plant has poor parameters in terms of pH, and moderate parameters in terms of humic substance content. An experiment using the bearded iris (Iris barbata) demonstrated that sewage sludge from the "Stróże" treatment plant stimulates plant growth. Therefore, it can be used both for ground rehabilitation, and for fertilization. Considering its properties and its broad spectrum of potential uses, sewage sludge should be viewed as a resource rather than a waste product. [ABSTRACT FROM AUTHOR]

The concentrations of nutrients (total nitrogen, total phosphorus and organic matter) and metals (Cu, Pb, Zn, Ni, Cd, Cr, As and Hg) in sewage sludge samples were determined to evaluate the level of contamination. Sewage sludge samples were collected from ten wastewater treatment plants from 2016 to 2018 in Wuxi city, China. All the studied sewage sludge samples displayed high fertility properties due to their richness. Total concentrations of metals in the sewage sludge samples were within the regulation of the Chinese legislation. The levels of the eight metals temporally varied. Sewage sludge pollution assessment was undertaken using pollution index, geo-accumulation index, potential ecological risk index and aggregative toxicity index. Multivariate statistical analysis indicated that Pb, Cr, As and Hg may have similar transport behavior and derive from anthropogenic sources. Ecological risk assessment revealed that Hg contamination is the major concern for human health, since the treated sewage sludge is used for agricultural purposes. [ABSTRACT FROM AUTHOR]

The goal of the study was to evaluate bioaccumulation of trace elements in plants grown in post-mining soils amended with the biosolids material. Phaseolus vulgaris was investigated on the laboratory scale, and a mixture of grasses, Melilotus albus, Beta vulgaris, Zea mays L. and Miscanthus × giganteus were evaluated on the field scale. The results of the research showed that P. vulgaris fertilized with the Carbocrash substrate was able to grow. In addition, growth was enhanced following stimulation with gibberellic acid. Transfer of trace elements should be evaluated on the plot scale. Therefore, we monitored the level of trace elements on an experimental plot in a reclaimed area. Crops plants were sown in multi-year periods. During the growing season the mixture of grasses and crop plants had a low bioaccumulation factor, which also showed a positive effect of fertilization with the Carbocrash substrate. [ABSTRACT FROM AUTHOR]

A greenhouse pot experiment with biochar (BC) applied at 0%, 1%, 4% and 8% (w/w) in monoculture and intercropping settings was used to investigate Cd, Cr and Zn speciation in contaminated soils, the growth of two different plant types, and the heavy metal concentrations within these plants. The results showed that BC application increased the soil pH, decreased the bioavailability of Cd, Cr and Zn, significantly increased the dry biomass of Cassia occidentalis and Machilus pauhoi shoots and slightly increased the root biomass. Both BC addition and intercropping decreased the Cd, Cr and Zn contents in the M. pauhoi shoots and roots, but the effect of BC addition was more significant than the effect of intercropping. The Cd, Cr and Zn uptake by M. pauhoi shoots was reduced by up to 93.91%, 96.41% and 76.76%, respectively, when the concentration and bioavailability of Cd, Cr, and Zn were reduced by using the combination of intercropping and BC application. This treatment resulted in the greatest reduction efficiency, and resulted in a shoot biomass increase of M. pauhoi of up to 122.52% compared to the control ( M. pauhoi monoculture). These results could be used as a reference for the promotion of M. pauhoi growth and the utilization of contaminated land. [ABSTRACT FROM AUTHOR]

The aim of this paper is to assess the effect of liming and low doses of municipal sewage sludge (5%, 10%, 15% of the soil mass) on lead, chromium and nickel speciation in soil. The 420-day experiment was carried out in laboratory conditions. In all the samples lead, chromium and nickel concentration was determined with the ICP-AES method, while the content of those metals in different fractions was measured with the seven-step Zeien and Brümmer method, on the 30th and 420th days of the experiment. Sewage sludge doses significantly diversified lead, chromium and nickel amounts in the soil. The highest dose of sludge caused a significant increase, compared to the control, in the content of those metals. In the sludge the dominant forms of metals tested in the experiment were lead and chromium bound to organic matter (F4) as well as nickel bound to amorphous iron oxides (F5). Liming decreased the mobility of the metals in the soil. [ABSTRACT FROM AUTHOR]

The current study evaluates the impact of sewage sludge and urban reservoir sediment on changes in total and Toxic Equivalency (TEQ) PCDD/PCDF concentration in soil and phytotoxicity measured using three test species: Lepidium sativum, Sinapis alba, and Sorghum saccharatum, during 5 weeks of Cucurbita pepo L. cv 'Atena Polka' (zucchini) cultivation. 'Atena Polka' was found to reduce total PCDD/PCDF concentration by 37 % in soil amended with sludge and 32 % in soil treated with sediment from an urban reservoir. The TEQ reduction was almost twofold greater: 68 % in soil amended with sludge and 52 % with urban sediment. Addition of sludge increased root growth inhibition of L. sativum, S. alba and S. saccharatum, from 44 % to 90 %. Observed inhibitions were, however, reduced by 'Atena Polka' cultivation, and as high as 32 % promotion in root length was noted. Amendment with urban sediment, in turn, resulted in an initial 1 %-36 % promotion of root growth, while 'Atena Polka' cultivation reduced this positive effect by inhibition as high as 26 %. Results demonstrated positive influence of 'Atena Polka' on the phytotoxicity alleviation and mitigation of total and TEQ PCDD/PCDF concentrations in soil treated with bio-solids from sewage sludge and an urban reservoir. [ABSTRACT FROM AUTHOR]

Although sewage sludge is a rich source of nutrients for arable farming and soil improvement, it can also be a source of pollutants. The effects of the land application of sludge on the PCB and nutrient content of leachate were investigated using cylindrical 650 mm length columns filled with poor quality soil. Treatments included no fertilization (control), fertilization using a 62.5 t/ha dose (O50) of sewage sludge from the largest Polish Wastewater Treatment Plant, in Lodz, and a 62.5 t/ha dose of sewage sludge mixed with CaO (O50Ca). The leaching of sludge-borne PCBs and nutrients was simulated by the application of distilled water in a quantity reflecting the annual rainfall of 562.5 mm. The obtained results demonstrate that application of sewage sludge and water simulated leaching of the most mobile chemical compounds, nitrate for example, whereas the addition of CaO decreased the average PCB and phosphorus concentrations in comparison to the control and O50 samples. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to study the accumulation and translocation of metals in French bean ( Phaseolus vulgaris L.). Plants were grown in soil amended with up to 100 % sewage sludge. Significant ( p < 0.01) changes to soil characteristics were observed. The maximum growth of P. vulgaris was noted in the treatment with 40 % of sewage sludge. Metal concentrations were significantly ( p < 0.05) higher in P. vulgaris after sewage sludge amendment where Fe > Zn > Cd > Cu > Cr > Pb. The translocation for Fe and Zn was in the order of leaves > shoot > root > fruits, for Cd, shoot > root > leaves > fruits, for Cu and Pb shoot > leaves > root > fruits and for Cr root > shoot > leaves > fruits of P. vulgaris. All accumulated metal concentrations except Cd in the fruit were below the FAO/WHO standard limits. Thus, the amendment of agricultural soil by sewage sludge might be feasible. However, a regular monitoring of metal levels in agricultural products is recommended to prevent their accumulation in the food chain. [ABSTRACT FROM AUTHOR]

In Brazil, the policy for disposing industrial sludge is changing from an emphasis on using controlled landfills to other treatment or co-processing methods; however, the monitoring of organic pollutants is not mandatory. The present study evaluated two general screening methods for organic pollutants in sludge generated in an automotive industrial complex in southern Brazil. The screening was performed using Soxhlet and sonication extractions and Gas Chromatograph coupled with Quadrupole Mass Spectrometry (GC/qMS). It was concluded that both techniques were effective and that most of the compounds identified were alkanes, phenols and esters. Important pollutants were detected in the sludge, which confirms the necessity of monitoring this type of residue. [ABSTRACT FROM AUTHOR]

The purpose of this study was to determine the leaching characteristics of heavy metals from artificial soils composed of sewage sludge and fly ash. A leaching experiment was carried out over a period of 90 days. The leachates from artificial soils were collected every 15 days, and the concentrations of cadmium, lead, copper, zinc, chromium, and nickel in leachates were determined. Results showed that pH values of the artificial soils leachate were stable, ranging from 6.71 to 7.62 at the end of the experiment. Except of the cadmium, the concentrations of chromium, nickel, and copper in leachates of the artificial soils reached a stable level at the end of the experiment. The final concentrations of copper in leachates varied from 27.1 to 127.5 μg L, which was lower than European threshold value for drinking water, (1,000 μg L), while final nickel and chromium concentrations in leachates exceeded the European threshold ones. Amorpha fruticosa and Robina pseudoacacia grown in the artificial soils had different effects on cadmium, nickel, chromium, and copper leaching behavior. Amorpha fruticosa resulted in higher Ni and Cu concentrations in leachates, while Robina pseudoacacia enhanced leaching concentration of Cr. [ABSTRACT FROM AUTHOR]

Seven typical synthetic musks were measured in influents, effluents and sewage sludge from seven wastewater treatment plants of Beijing in three seasons. Galaxolide and tonalide were the dominant musks, and the levels were medium compared with those from other regions. Musk concentrations and galaxolide/tonalide ratios were low in warm seasons relative to cold seasons in both water and sludge samples. The removal efficiencies of galaxolide and tonalide ranged in <14.3%-98.0% and <18.5%-98.7%, respectively. The discharge of galaxolide and tonalide through effluents into environment were 1.8-685.6 g/d (mean: 70.1 g/d) and 1.6-195.3 g/d (mean: 22.9 g/d), respectively. [ABSTRACT FROM AUTHOR]

A study of organic compounds which caused several odor problems in water supplies from NW Spain was carried out. Sour dish-cloths, potato bin and musty were the main descriptors associated with these events. Closed loop stripping analysis combined with sensory-GC and GC/MS detection was used. The compound producing the initial odor event was 3,5-dimethyl-2-methoxypyrazine, identified for the first time as the compound responsible for odor incidents in finished water. Concentration levels were up to 300 ng/L in the effluent from an activated sludge wastewater treatment plant (WWTP) and 3 ng/L in finished water. 3-isobutyl-2-methoxypyrazine and other alkyl methoxypyrazines were the compounds responsible for the odor events that occurred several months later. Concentration levels in the mg/L range were measured in the activated sludge of a WWTP. [ABSTRACT FROM AUTHOR]

Using sewage sludge, a biological residue from sewage treatment processes, in agriculture is an alternative disposal technique of waste. To study the biochemical and physiological responses of Rice ( Oryza sativa L.) grown on different sewage sludge amendments (SSA) rates a field experiment was conducted by mixing sewage sludge at 0, 3, 4.5, 6, 9, 12 kg m−2 rate to the agricultural soil. Rate of photosynthesis and stomatal conductance increased in plants grown at different SSA rate. Chlorophyll and protein contents also increased due to different SSA rates. Lipid peroxidation, ascorbic acid, peroxidase activity and proline content increased, however, thiol and phenol content decreased in plants grown at different SSA rates. The study concludes that for rice plant sewage sludge amendment in soil may be a good option as plant has adequate heavy metal tolerance mechanism showed by increased rate of photosynthesis and chlorophyll content and various antioxidant levels. [ABSTRACT FROM AUTHOR]

Stabilized sewage sludge (SS) by fly ash (FA) and alkaline mine tailing as artificial soil, to be applied on the ecological rehabilitation at mining junkyard, offers a potential viable utilization of the industrial by-product, as well as solves the shortage of soil resource in mine area. In this study, trace element and heavy metal soil solution concentrations arising from fly ash, sewage sludge, mine tailing, and artificial soil mixtures were investigated in a laboratory incubation. It was found that total Cd, Pb, and Zn contents in artificial soils were significantly lower than the control standards for pollutants in sludges from agricultural use (GB 4284-84). Soil solution Cd and Pb concentrations were obviously reduced by mixing sewage sludge with alkaline fly ash. Initial soil solution Cd, Pb, and Zn concentrations in artificial soils were 1.773–14.672, 4.05–24.95, and 133–608 μg L−1, respectively, and after 35-days incubation, soil solution Cd, Pb, and Zn concentrations gradually decreased and were approaching control levels by the end of the experiment, and finial soil solution were decreased to 0.037–0.365, 2.12–7.34, and 29–509 μg L−1, respectively. [ABSTRACT FROM AUTHOR]

Enantioselective degradation occurs frequently for chiral pesticides in field matrices and under laboratory conditions. Metalaxyl is a chiral compound and important fungicide. In this study, the degradation of Rac- and R-metalaxyl under anaerobic conditions was studied. The degradation processes were found to follow first-order kinetics. The degradation of the S-enantiomer ( T 1/2 = 2.10 days) was much faster than the R-enantiomer ( T 1/2 = 8.44 days). The half-life of the Rac-metalaxyl mixture was 4.05 days, which was higher than the S-enantiomer, but lower than the R-enantiomer. These results confirm the need for emphasizing the importance of examining the fate of the stereoisomers in an environmental system. [ABSTRACT FROM AUTHOR]

This study was carried out to evaluate the agricultural usage of an anaerobically digested sludge in the contents and fractions of heavy metals. Therefore, a sequential extraction scheme according to the BCR’s (Community Bureau of Reference) guidelines and total acid digestion were applied to sewage sludge samples. The results of total heavy metal concentrations in sewage sludge showed that the highest total concentrations were Fe, Zn and Mn. When Turkish, Europe and US EPA directives were compared with each other by depending on the use of sludge for agricultural purposes, all the heavy metals determined for this sludge were below the maximum permitted levels, except for Cd. This sludge should not be applied to land due to its high Cd content. The results of heavy metal fractions indicated that some metals (Cd, Mn, Pb, and Fe) distributed mainly in the residual fraction. All fractions of Zn showed no variation. Cu and Cr were most abundant in the oxidizable phase while Ni was in exchangeable phase. Although total content of Ni in the sludge is lower than the maximum levels allowed by all the directives, it tends to be easily moved and dispersed in the environment. Due to its high mobility, the examined sewage sludge may cause phyto-toxicity after its agricultural application. [ABSTRACT FROM AUTHOR]

This study was to evaluate the degradation efficiency of naturally contaminated polycyclic aromatic hydrocarbons in sewage sludge by using electron beam irradiation as a function of the absorbed dose. Degradation efficiency of PAHs was near to 90% at the absorbed doses 5 kGy. The degradation of PAHs was “first order” reaction rates with respect to absorbed dose. The electron beam irradiation was found effective in means of removing PAHs in domestic wastewater. [ABSTRACT FROM AUTHOR]

This article discusses the physicochemical properties of artificial soil mixed with fly ash, sewage sludge and mine tailings in China. Water holding capacity was measured with simulated rainfall evaporation and heavy metals (copper, lead, zinc and nickel) were analyzed by atomic absorption spectrophotometry. According to the authors, after several days, most artificial soil mixtures increased in water holding capacity, pH increased indicating decreasing acidity, and the electrical conductivity decreased indicating less salinity in the soil. Heavy metals were found to be below the toxicity thresholds.

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This article investigates the long-term application of sludge and water from a sewage treatment plant to an olive tree plantation in Greece. From the analysis of data from treated plants and the comparison with those from naturally growing olive trees, it can be pointed out that, for lead and zinc, no accumulation was detected, even after the long-term culture, in soil amended with sludge. The concentration of cadmium seems increased in treated plants. For chromium, copper, manganese and nickel, a minor increase is detected.

This article presents a study which discusses various issues related to biocides in sewage sludge in some Swiss wastewater treatment plants. Biocides released by private households and the industry may enter wastewater streams directly or they may end up in wastewater after aerial deposition on impervious surfaces and runoff into sewer systems. In wastewater treatment plants, lipophilic substances are mainly adsorbed onto sewage sludge. Sludge is an appropriate matrix for the characterization of the release of numerous xenobiotic compounds. The present study aims to determine: the concentrations of biocides in sewage sludge; the specific loads of biocides in sewage sludge sampled in different types of monitoring sites; and their main sources.

This article focuses on degradation of a hydrolyzable tannin from cascalote. Tannin compounds became a contaminant in the environment because their biodegradation persistence and the increasing amount of sludge or waste water effluent to the environment in the last years. During leather processing using tannin, an excess of phenolic compounds are discarded as sludge or in the waste water stream. The biodegradation of tannin in contaminated sites using enzymatic system is an attractive alternative to solve the problem of pollution in the environment.

This article focuses on speciation of heavy metals in sewage pastures. Domestic sewerage contains significant concentrations of potentially toxic contaminants, including heavy metals (e.g. cadmium, zinc, cobalt, nickel, lead, mercury, boron), other metal ions (e.g. sodium, potassium, magnesium, calcium), pesticide residues (e.g. atrazine and its degradation products), other endocrine disrupting organic compounds such as PCBs, PCDD/PCDFs, polycyclic aromatic hydrocarbons (PAHs), alkyl phenols, phthalates, phyto and synthetic estrogens, and pathogenic micro-organisms.

The article presents a study that investigated the feasibility of making organic complex fertilizer using composted sludge. The dried sludge from the Fourth Sewage Treatment Plant contained 3 9.6% organic matter, on average. Nitrogen, phosphorus and potassium content were 48.3g/kg, 21.lg/kg and 8.5 g/kg on average, respectively. The plant nutrient content was the. same as or a little higher than the sludge in other cities such as Guangzhou, and Tianjin in China. The sludge from the Fourth Sewage Treatment Plants in Guilin contained 39.6%. organic matter on average.

This article focuses on the residual effects of sewage sludge. Agricultural application of sewage sludge is becoming popular as a means of nutrient recycling in many areas of the world. Guidelines on application of sewage sludge should take account of many factors, such as sludge type, time, and method of application. Because of a growing need to apply municipal sewage sludge on agricultural lands, there is a developing urgency to have criteria for disposal practices that will preserve the productivity of these lands and prevent entry of potentially toxic elements.

The article cites a study conducted to determine degradation of nonylphenol ethoxylates (NPE) in sewage sludge and source separated municipal solid waste under bench-scale composting conditions. Experiments were conducted in a laboratory scale composting system that made it possible to keep the compost at a fixed temperature for extended periods of time and simultaneously ensure an adequate oxygen supply to the compost microorganisms. In the study with sewage sludge, composting at temperatures from 35°C to 55°C resulted in a net degradation of 4-NP and there were no sign of other degradation products.

The article reports on alkaline pretreatment of kraft mill sludge to improve its anaerobic digestion. Aerobic processes are the most common technologies used in wastewater treatment plants, particularly in the pulp and paper industry. The activated sludge process presents a high biological oxygen demand removal efficiency, but generates 0.5 kg dry weight excess sludge. This excess sludge must be treated for stabilization and mineralization of the organic matter present otherwise it creates a major atmospheric hazard. The main objective of this article is to study the alkaline pretreatment of the excess sludge produced in the aerobic kraft mill wastewater treatment process, for further enhancement of anaerobic digestion.

This article focuses on a study that was conducted to analyze the influence of pH and industrial activity on total zinc concentrations in agricultural soils, sewage sludge and beach sands. Samples for the present study were directly obtained from Motril, Spain. Mean total zinc concentrations determined in the three groups of samples considered were significantly different among them, particularly zinc levels measured in sewage sludge and agricultural soils were statistically higher than those found in sands. This finding indicates the influence of the geological characteristics of soil in the total content in zinc. It was also found that the pH values of agricultural soils located in the non-industrialized area were significantly higher. This finding shows a slow and progressive acidification of soils included in the industrialized area.

The article determines the effect that sewage sludge and wastewater have on the yield and quality of plant products, to trace any heavy metals along various parts of the plants and to investigate their concentrations. It appears that sewage sludge promoted seed production up to 435.4 % and fiber production up to 366.4 % or 2469.5 %. Irrigation with waste water, in addition to sludge application, usually promotes production even more. The quality of cotton fibers from the various groups did not seem to change.

The article investigates the impact of sewage sludge and wastewater on the phenology, growth and productivity of cotton plants. Use of sewage sludge results in significantly higher, more robust plants with faster development and significantly greater stem biomass and root biomass production. On the other hand, irrigation with wastewater instead of tap water results in significant differences in root biomass and leaf surface in combination with high ratio of sewage sludge. Phenological observations indicated that in the sludge groups flowering and fruition started 2-3 weeks earlier compared to that of the fertilization group.

The article examines the toxicity level of wastewater sludges from tanning, agrochemical, brewery and food industries using Amphipod biological assays. An alarming mortality rate from tannery and brewery wastes was observed, while a reverse pattern was noted from the food industries. The result of the study correlated with conductivity and volatile solids (VS) that attributed sludge toxicity to a combined effect of these two factors. Furthermore, the researchers concluded that the relationship between mortality and VS percentage resulted from the introduction of chemicals during sludge feeding or an incomplete stabilization process.

The article cites a study that examines the toxic effect of two sewage sludges such as activated sludge (AcS) and raw sludge (KS) on juvenile Cirrhina mrigala (C. mrigala), a fresh water edible fish. Physical deterioration were manifested among the C. mrigala in the fourth day of the on set of the experiment, with significantly increasing mortality rate among fishes fed with AcS than those maintained on KS due to the concentrated suspension of aerobic microorganism in AcS. With the action of xenobiotics in the sludges that caused death to young C. mrigala, it has been suggested that further studies and caution in the use of the sludges as a nutritive substitute in fish culture should be considered.

The article presents a study which investigates the acute toxicity of chromium, lead, and other heavy metals to aquatic ciliated protozoa from activated sludge plants in Reggio Emilia in Italy. The study made use of the filtered Evian natural water as dilution water for heavy metals such as lead chloride, hydrated cadmium chloride, and potassium dichromate. The result of the study shows that lead was more toxic than chromium to ciliate populations.

The article presents a study which characterizes and identifies the toxic constituents in a process water that was proven chronically toxic to the daphnid Ceriodaphnia dubia. The study used aerobic sequencing batch reactor, the Continuous Activated Sludge System (CASS), a standard short-term chronic test, and chemical analyses. Results show that the short-term chronic test has confirmed the 100% survival of Ceriodaphnia dubia,

The article presents a study which investigates the concentration of selenium and cadmium in various swiss chard grown in compost. The study use four composts including sewage sludge, sewage sludge and yard waste, and sewage sludge, yard waste, and municipal solid waste (MSW). Result show that the concentration of the two element minerals depend on several factors such as the element contents in the compost, nature of the plant, and the volume of compost.

The article presents a study on the acute toxicity of ciliate on activated sludge plants on various heavy metals including cadmium, copper, and zinc. The study uses various methods such determining the median lethal concentrations of the ciliates using probit method, and checking the mortality of the species after inoculation on sterile medium. Results show the difference of toxicity of zinc and copper on ciliates with other heavy metals, and the toxicity of Daphnia magna on heavy metal salts.

The article presents the study which aims to evaluate the accumulation of the heavy metals on the dietary earthworms which was collected from sewage sludge. It uses the least shrew or the Cryptotis parva, a secondary consumer wherein its natural diet includes earthworms which is a good indicator of heavy metal transfer. Result shows the differences in the heavy metal content of shrews inhabited in sludge-treated and untreated ecosystem.

The article presents a study which examines the influence of environmental factors on the process of sodium dodecyl-benzene-sulphonate degradation in seawater with the presence of marine sludge. The study used Abbot's Methylene Blue method, granulometric analysis, and atomic absorption spectroscopy. Results show that there was no significance on the percentage of the degradation over the experimentation and the illuminated samples has achieved 90% degradation.

The article presents a study which investigates variation in the properties of sewage sludge. The study used a sewage treatment plant combined sewerage in which the activated sludge process (step aeration method). Moreover, the study revealed that sludge concentration decreases in winter and increases in summer.