Eco(geno)toxicity of the new commercial insecticide Platinum Neo, a mixture of the neonicotinoid Thiamethoxam and the pyrethroid Lambda-Cyhalothrin.

New mixtures of pesticides are being placed on the market to increase the spectrum of phytosanitary action. Thus, the eco(geno)toxic effects of the new commercial mixture named Platinum Neo, as well as its constituents the neonicotinoid Thiamethoxam and the pyrethroid Lambda-Cyhalothrin, were investigated using the species Daphnia magna, Raphidocelis subcapitata, Danio rerio, and Allium cepa L. The lowest- and no-observed effect concentration (LOEC and NOEC) were measured in ecotoxicological tests. While Thiamethoxam was ecotoxic at ppm level, Lambda-Cyhalothrin and Platinum Neo formulation were ecotoxic at ppb level. The mitotic index (MI), chromosomal aberrations and micronucleus [MN] frequency were measured as indicators of phytogenotoxicity in A. cepa plants exposed for 12 hours to the different insecticides and their mixture under different dilutions. There were significant alterations in the MI and MN frequency in comparison with the A. cepa negative control group, with Thiamethoxam, Lambda-Cyhalothrin, and Platinum Neo treatments all significantly reducing MI and increasing MN frequency. Thus, MI reduction was found at 13.7 mg L-1 for Thiamethoxam, 0.8 µg L-1 for Lambda-Cyahalothrin, and 2.7:2 µg L-1 for Platinum Neo, while MN induction was not observed at 14 mg L-1 for Thiamethoxam, 0.8 µg L-1 for Lambda-Cyahalothrin, and 1.4:1 µg L-1 for Platinum Neo. The insecticide eco(geno)toxicity hierarchy was Platinun Neo > Lambda-Cyhalothrin > Thiamethoxam, and the organism sensitivity hierarchy was daphnids > fish > algae >A. cepa. Eco(geno)toxicity studies of new pesticide mixtures can be useful for management, risk assessment, and avoiding impacts of these products on living beings.

Degradation of cytostatics methotrexate and cytarabine through physico-chemical and advanced oxidative processes: influence of pH and combined processes on the treatment efficiency.

Environmental release of wastewater that contains cytostatic drugs can cause genotoxic impact, since these drugs act directly on the genetic material of aquatic organisms. Thus, the aim of this study was to evaluate the removal of the cytostatic drugs cytarabine (CTR) and methotrexate (MTX) using different physico-chemical methods individually (i.e. US, O3, H2O2 and UV) and combined (i.e. O3/US, US/H2O2, O3/H2O2 and O3/US/H2O2) under different pH conditions (4, 7 and 10). In the degradation tests, the efficiency of the methods applied was found to be dependent on the pH of the solution, with the degradation of CTR being better at pH 4 and MTX at pH 7 and pH 10. The US, H2O2 and US + H2O2 methods were the least efficient in degrading CTR and MTX under the pH conditions tested. The highest MTX degradation rate after 16 min of treatment at pH 7 was achieved by the O3 + H2O2 method (97.05% - C/C0 = 0.0295). For CTR, the highest degradation rate after 16 min of treatment was achieved by the O3 process (99.70% - C/C0 = 0.0030) at pH 4. In conclusion, most of the treatment methods tested for the degradation of CTR and MTX are effective. Notably, ozonolysis is an efficient process applied alone. Also, in combination with other methods (US + O3, O3 + H2O2 and O3 + H2O2 + US) it increases the degradation performance, showing a rapid removal rate of 70-94% in less than 4 min of treatment.

Using photocatalyzed-peroxonization to disinfect and denature genetic material of bacterial plasmids present in hospital wastewater.

The literature reports the presence of multiresistant microorganisms in wastewater discharged from municipal and hospital wastewater treatment plants (WWTPs). This has led to questions concerning the disinfection efficiency of the treatments applied. Thus, this study aimed to assess the efficiency of different chemical oxidation methods to disinfect and to degrade bacterial plasmids present in hospital wastewaters, to avoid the dispersion of antibiotic resistance genes in the environment. The methods tested were UV254nm alone or associated with an Ag or Ti-photocatalyst in photo-peroxonization (UV254 nm/H2O2/O3/Ag2O/Ag2CO3@PU or UV254 nm/H2O2/O3/TiO2@PU) under different pH conditions (4, 7, and 10). The application of plasmid DNA electrophoresis to hospital wastewater treated using an advanced oxidation process (AOP) achieved the total structural denaturation of microorganism plasmids at the three pH values tested. Also, UV254 nm alone was partially efficient in the disinfection of hospital wastewater. AOPs performed with the two functionalized catalysts resulted in 100% disinfection after 10 min at the three pH values tested. No intact plasmids were observed after 20 min of treatment with photocatalysis. This study could contribute to the development and improvement of wastewater treatment aimed at mitigating the spread of multiresistant microorganisms in the environment.

Swine slaughterhouse biowaste: an environmental sustainability assessment of composting, amended soil quality, and phytotoxicity.

In this article, the environmental sustainability of a circular economy concept applied to the management of biowaste was studied. To achieve this goal, the composting performance, compost-amended soil health, and phytotoxicity were assessed in the case of management of solid waste from a small swine slaughterhouse. Microorganisms present in a similar composting process were used as inoculums to improve the efficiency of composting. Addition of the inoculum promoted a faster and more efficient composting process than composting without the inoculum. The physical, chemical, and microbiological characteristics of soil were considered to be improved after compost application. Phytotoxicity tests in soils with and without compost amendment showed that a soil-compost mixture (90:10 and 70:30 mass ratios) was not phytotoxic to the plant species Sorghum saccharatum and Lepidium sativum, and that soil with compost showed higher plant biomass growth than that without compost amendment. The triple bottom line methodology used in this study can help in the assessment of circular economy activity in relation to the environmentally sustainable management of solid waste generated in small swine slaughterhouses.

Antibiotic degradation and mineralization: efficiency increase on combining different chemical treatment processes.

The goal of this study was to assess the efficiency of antibiotic degradation applying different chemical treatment methods and their combinations. Thus, improvement in the efficiency of these methods when combined was quantified. The methods tested to degrade/mineralize the antibiotics amoxicillin (AMX) and ciprofloxacin (CIP) under different pH conditions (4, 7 and 10) were ultra-violet irradiation (UV254 nm), ultrasound (US), hydrogen peroxide (H2O2) and ozone (O3) alone and in combination. The results showed that individual methods were only partially efficient in the degradation/mineralization of antibiotics, except for ozonation at alkaline pH. In the combined methods, the best performance was obtained with US/UV/H2O2/O3 (pH 10, 20-min treatment), where the degradation rates for the antibiotics were 99.8% for CIP and 99.9% for AMX. For the mineralization efficiency the values obtained were 71.3% for CIP and 79.2% for AMX. The results of this study could contribute to the development and improvement of wastewater treatment aimed at avoiding the presence of residual antibiotics in the environment.

Development of a low-cost inoculum to improve composting of cattle slaughterhouse by-products.

The composting process is an option for acceptable environmental management of cattle slaughterhouse by-products. The goals of this article were (i) to make a low-cost inoculum using popular supermarket ingredients and microorganisms that are already present in the composting environment, and (ii) to compare the efficiency of the composting process with and without the application of formulated inoculum. Initially, a consortium of microorganisms already present in the composting environment (Saccharomyces cerevisiae, Bacillus subtilis, and Rhodopseudomonas palustris) was prepared in a low-cost culture medium for use as an inoculum for the composting process. The composting process with the addition of the inoculum was more efficient than the composting process without the inoculum, in terms of both the chemical composition and the process efficiency, but mainly in relation to the time required for composting, with the mean times for decay of 50% of the windrows' temperature (taking in to account the difference between internal and external windrow temperatures) being 96 days without inoculum and 65 days with inoculum. Thus, inoculum made with low-cost supermarket products reduced the composting time and yielded compost of better quality.

Urban afforestation: using phytotoxicity endpoints to compare air pollution tolerance of two native Brazilian plants Aroeira (Schinus terebinthifolius) and Cuvatã (Cupania vernalis).

Urban afforestation can mitigate the effects of air pollution, but the suitability of plant species for this purpose needs to be determined according to pollution intensity and climate change. The goal of this study was to evaluate the sensitivity of different phytotoxicity endpoints using two native Brazilian plant species as models, Aroeira (Schinus terebinthifolius) and Cuvatã (Cupania vernalis). The sensitivity parameters evaluated could help in selecting the most air-pollution-tolerant plant species for use in urban afforestation programs. The two plant species were exposed, in a greenhouse, to the combustion gases of a diesel engine for 120 days, with daily intermittent gas exposure. Every 30 days, leaf injury (chlorosis and necrosis), biomass, and physiological/biochemical parameters (proteins, chlorophyll, and peroxidase enzyme activity) were evaluated for both plant species. For the two selected species, the endpoints studied can be ranked according to their sensitivity (or inversely the tolerance) to diesel oil combustion gases in the following order: peroxidase > biomass ≈ chlorophyll > protein > leaf injury. The endpoint responses of higher plants can be used to assess the suitability of particular plant species for use in urban afforestation areas with relatively intense vehicle traffic.

Degradation of recalcitrant textile azo-dyes by fenton-based process followed by biochar polishing.

The use of advanced oxidative processes (AOPs) is an efficient alternative for the treatment of textile wastewaters. The aim of this study was to assess the dye removal efficiency of a Fenton-based degradation process followed by a polishing step using biochar prepared from rice husk. Six recalcitrant textile dyes - Reactive Red 195 (D1), Synolon Brown S2 (D2), Orange Remazol RGB (D3), Yellow Synozol K3 (D4), Reactive Orange (D5), and Reactive Black 5 (D6) - were treated with Fenton and photo-Fenton processes (with and without biochar polishing) under optimized conditions. The results showed a general efficiency ranking: photo-Fenton + biochar ≈ Fenton + biochar > photo-Fenton ≈ Fenton. The Fenton process was also efficient for the regeneration of the dye-saturated biochar. The photo-Fenton + biochar process achieved the following color removal percentages: D1 (98.8%), D2 (99.7%), D3 (98.9%), D4 (96.3%), D5 (94.2%) and D6 (94.8%). This process was applied to a real conventionally-treated textile wastewater and analysis showed a reduction in BOD (87.5% degradation), COD (62.5% degradation) and color (93.5% mean removal). These results reveal the possibility for the reuse of the treated water for non-potable industrial uses, for example, floor washing or the cleaning of machines and toilet areas.

Assessment of phytotoxicity and impact on the enzymatic activity of soil microorganisms caused by veterinary antibiotics used in Brazilian farms.

This work aimed to evaluate the impact of veterinary antibiotics on biomass phytoproductivity and soil enzyme activity. The soil was sampled in the city of Camboriú (state of SC, Brazil). The soil enzyme activity was assessed through hydrolysis of fluorescein diacetate (FDA), while phytotoxicity was tested using Lactuca sativa (lettuce). Results showed that the most appropriate exposure time to assess the impact of antibiotics on soil microbiology was 24 h, while the incubation time of 3 h was the most appropriate for FDA hydrolysis. Ampicillin and Amoxicillin at the tested concentrations did not interfere with the enzyme activity of the soil microbiota, while Oxytetracycline and Neomycin showed a significant reduction in soil enzyme activity. For the dry and wet biomass of lettuce, 2% Colistin and 1% Ampicillin were the treatments that reduced lettuce biomass. Hence, the use of excessive antibiotics in animal production may lead to environmental impacts and, in the future, to public health problems.

Using textile industrial sludge, sewage wastewater, and sewage sludge as inoculum to degrade recalcitrant textile dyes in a co-composting process: an assessment of biodegradation efficiency and compost phytotoxicity.

Recalcitrant dyes found in textile wastewater represent a threat for sustainable textile production due to their resistance to conventional treatments. This study assessed an alternative co-composting system for the treatment of recalcitrant textile dyes where textile industrial sludge, sewage wastewater, or sewage sludge were used as microbial compost inocula. The biodegradation efficiency of bioreactor trials and compost quality of the co-composting system were assessed by visible spectrophotometry and by a phytotoxicity test. The co-composting system (dry weight (dw) basis) consisted of 200 g of restaurant organic residues + 200 g sewage sludge (or 100 mL sewage wastewater, or 200 g textile sludge) + 100 mL of a 10% dye solution (Reactive Red 195, or Synolon Brown, or Orange Remazol, or Yellow Synozol, or Reactive Orange 122, or Reactive Black 5). After 60 days of composting, all dyes were biodegraded according to spectrophotometric data, with efficiency varying from 97.2 to 99.9%. Inoculum efficiency ranking was textile sludge > sewage sludge > sewage wastewater. Regarding compost quality, a phytotoxicity study with lettuce showed no toxicity effect. Thus, co-composting can be a low-cost and efficient method for recalcitrant textile dye biodegradation and for managing textile sludge in terms of waste recycling, contributing to environmental sustainability.

Petroleum-contaminated soil: using sonolysis to improve mineralization and biodegradation potential of Fenton reaction and ozonolysis process.

The degradation efficiency of the Fenton reaction or ozonolysis (O3) to treat soil contaminated by crude petroleum was studied in association with the sonolysis process. To quantify oxidation efficiency, total organic carbon (TOC) and chemical oxygen demand (COD) were measured, while biochemical oxygen demand (BOD5) was measured to estimate biodegradation potential. TOC removal efficiency ranged from 9 to 52% to the Fenton reaction without sonolysis, and 18% and 78% with sonolysis for reagent concentrations of 1% H2O2-100 mM Fe2+ and 20% H2O2-1 mM Fe2+, respectively. For ozonolysis (after 10 and 60 min of treatment), the reduction in TOC ranged from 9 to 43% without sonolysis and 15 to 61% with sonolysis. The Fenton reaction without sonolysis increased the biodegradability in relation to the non-oxidized sample by 6% (1% H2O2-100 mM Fe2+) and 26% (20% H2O2-1 mM Fe2+), and with sonolysis the corresponding values were 13% and 42%, respectively. The biodegradation potential under ozonolysis without sonolysis increased from 0.18 (10 min of treatment) to 0.38 (30 min of treatment), and with sonolysis these values were 0.26 and 0.58, respectively. Optimization of the remediation processes is essential to determine sequential treatment order and efficiency.

A 3D ecotoxi-topological profile: Using concentration-time-response surfaces to show peroxidase activity in Zea mays (L.) exposed to aluminium or arsenic in hydroponic conditions.

This study sought to use concentration-time-response surfaces to show the effects of exposure to toxic (semi-)metals on peroxidase activity in higher plants as a function of exposure-concentration and exposure-time. Maize (Zea mays L.) seedlings (i.e., leaves and roots) were exposed to arsenic (as As3+) or aluminium (as Al3+) under hydroponic conditions, and their biomass and peroxidase enzyme responses were assessed at different concentration-time-exposures. The 3D ecotoxi-profile generated with these data showed two distinct regions: the first region is formed by exposures (i.e., points for time-concentration pairings) that were not statistically different from the results of the control points (i.e., zero toxicant concentration and all exposure-times), whereas the second region is formed by exposure pairings with results that were statistically different to those obtained from control pairings. Overall, the data show that enzyme activity increased over a shorter exposure-time when there was an increase in the exposure-concentration of the toxicant, which can be seen on a 3-D toxicity profile. We propose that quantitative relationship ratios from different assessed endpoints (e.g., biomass and enzyme activity) and enzymatic concentration-time-response surfaces could be helpful in the field of environmental-policy management.

Remediation efficiency of different methods for rapid-response of microbiological and/or organic matter contaminated beach sand: A laboratory study.

In this article we compare the efficiency of different methods of rapid-response remediation of beach sand contaminated with microbiological and/or organic matter. Contaminated beach sands were treated in laboratory by different treatment methods (i.e., oxidation, UV-photoexposure, or thermal methods) and the efficiency of disinfection and breakdown of organic matter were evaluated. Contaminants in raw and treated beach sands were measured by membrane filtration method, and by chemical and biochemical oxygen demand, and chromatographic analysis. All the methods tested were efficient for disinfecting beach sand with microbiological contamination, except for the UV-photoexposure method, which showed only moderate disinfection potential. Chemical degradation efficiency of beach sand contaminated by crude petroleum was higher with Fenton and Photo-Fenton (associated with the use of surfactant and ultrasound) methods. Photo-Fenton method improvement can increase the efficiency of contaminated beach sand treatment, and can also help beach managers when selecting which method to adopt for remedial actions.

Comparing different methods for fast screening of microbiological quality of beach sand aimed at rapid-response remediation.

There is scientific evidence that beach sands are a significant contributor to the pathogen load to which visitors are exposed. To develop beach quality guidelines all beach zones must be included in microbiological evaluations, but monitoring methods for beach sand quality are relatively longstanding, expensive, laborious and require moderate laboratory infrastructure. This paper aimed to evaluate the microorganism activity in different beach zones applying and comparing a classical method of membrane filtration (MF) with two colorimetric screening methods based on fluorescein (FDA) and tetrazolium (TTC) salt biotransformation to evaluate a new rapid and low-cost method for beach sand microbiological contamination assessments. The colorimetric results can help beach managers to evaluate rapidly and at low cost the microbiological quality of different beach zones in order to decide whether remedial actions need to be adopted to prevent exposure of the public to microbes due to beach sand and/or water contamination.

Restoration of areas degraded by alluvial sand mining: use of soil microbiological activity and plant biomass growth to assess evolution of restored riparian vegetation.

River or alluvial sand mining is causing a variety of environmental problems in the Itajaí-açú river basin in Santa Catarina State (south of Brazil). When this type of commercial activity degrades areas around rivers, environmental restoration programs need to be executed. In this context, the aim of this study was to assess the evolution of a restored riparian forest based on data on the soil microbial activity and plant biomass growth. A reference site and three sites with soil degradation were studied over a 3-year period. Five campaigns were performed to determine the hydrolysis of the soil enzyme fluorescein diacetate (FDA), and the biomass productivity was determined at the end of the studied period. The variation in the enzyme activity for the different campaigns at each site was low, but this parameter did differ significantly according to the site. Well-managed sites showed the highest biomass productivity, and this, in turn, showed a strong positive correlation with soil enzyme activity. In conclusion, soil enzyme activity could form the basis for monitoring and the early prediction of the success of vegetal restoration programs, since responses at the higher level of biological organization take longer, inhibiting the assessment of the project within an acceptable time frame.

Ecotoxicity assessment of particulate matter emitted from heavy-duty diesel-powered vehicles: influence of leaching conditions.

Concerns regarding the environmental impact of diesel exhaust particulate matter (DPM) have increased in recent years. Following emission to the atmosphere, these fine materials can sorb many contaminants at their surface, which can subsequently be released, for instance, due to physicochemical environmental changes. The desorption of contaminants from particulate matter will increase the environmental pollution and can promote ecotoxicological effects. In this context, the objective of this study was to assess the aquatic ecotoxicity profile of extracts of DPM obtained at two different pH values. Thus, after collecting particulate matter from the diesel exhaust of heavy engines, extracts were obtained with pure water (at pH 2.00 and 5.00) and with a mixture of three organic solvents (dichloromethane, n-hexane, and acetone). To assess the environmental impact of DPM, the exhaust extracts were used in a battery of aquatic bioassays including key organisms of the food chain: bacteria (Aliivibrio fischeri), algae (Scenedesmus subspicatus), daphnids (Daphnia magna), and fishes (Danio rerio). The aqueous leachate at natural pH (2.0) and solvent extracts were extremely ecotoxic, while the aqueous leachate at pH = 5.0 showed the lowest ecotoxicity. The global ranking of sensitivity for the biotests tested was daphnids > algae > bacteria > fishes. Thus, the use of this bioassay battery could improve our understanding of the impact of DPM on aquatic environments, which is dependent on the pH of the leaching process.

Aquatic ecotoxicity assessment of a new natural formicide.

BACKGROUND, AIM AND SCOPE: Agrochemicals could reach aquatic ecosystems and damage ecosystem functionality. Natural formicide could be an alternative to use in comparison with the more toxic formicides available on the market. Thus, the objective of this study was to assess the ecotoxicity of the new natural formicide Macex® with a battery of classical aquatic ecotoxicity tests. MATERIAL AND METHODS: Bacteria (Aliivibrio fischeri), algae (Pseudokirchneriella subcapitata), hydra (Hydra attenuata), daphnids (Daphnia magna), and fish (Danio rerio) tests were performed in accordance with international standardized methodologies. RESULTS: In the range of formicide concentrations tested (0.03 to 2.0 g L(-1)) EC(50) values varied from 0.49 to >2.0 g L(-1), with P. subcapitata being the most sensitive species and H. attenuata and D. rerio the most tolerant species to this product in aqueous solutions. CONCLUSIONS: This new formicide preparation can be classed as a product of low toxicity compared to the aquatic ecotoxicity of the most common commercialized formicides.

Incorporation of gypsum waste in ceramic block production: Proposal for a minimal battery of tests to evaluate technical and environmental viability of this recycling process.

Civil engineering-related construction and demolition debris is an important source of waste disposed of in municipal solid waste landfills. After clay materials, gypsum waste is the second largest contributor to the residential construction waste stream. As demand for sustainable building practices grows, interest in recovering gypsum waste from construction and demolition debris is increasing, but there is a lack of standardized tests to evaluate the technical and environmental viability of this solid waste recycling process. By recycling gypsum waste, natural deposits of gypsum might be conserved and high amounts of the waste by-product could be reused in the civil construction industry. In this context, this paper investigates a physical property (i.e., resistance to axial compression), the chemical composition and the ecotoxicological potential of ceramic blocks constructed with different proportions of clay, cement and gypsum waste, and assesses the feasibility of using a minimal battery of tests to evaluate the viability of this recycling process. Consideration of the results for the resistance to axial compression tests together with production costs revealed that the best formulation was 35% of plastic clay, 35% of non-plastic clay, 10% of Portland cement and 20% of gypsum waste, which showed a mean resistance of 4.64MPa. Energy dispersive X-ray spectrometry showed calcium and sulfur to be the main elements, while quartz, gypsum, ettringite and nacrite were the main crystalline compounds found in this formulation. Ecotoxicity tests showed that leachate from this formulation is weakly toxic toward daphnids and bacteria (EC(20%)=69.0 and 75.0, respectively), while for algae and fish the leachate samples were not toxic at the EC(50%) level. Overall, these results show that the addition of 20% of gypsum waste to the ceramic blocks could provide a viable substitute for clay in the ceramics industry and the tests applied in this study proved to be a useful tool for the technical and environmental evaluation of this recycling process, bacterial and daphnid tests being more sensitive than algae and fish tests.

Genotoxicity potential of a new natural formicide.

BACKGROUND, AIM, AND SCOPE: Assessment of environmental impacts from pesticide utilization should include genotoxicity studies, where the possible effects of mutagenic/genotoxic substances on individuals are assessed. In this study, the genotoxicity profile of the new formicide Macex® was evaluated with two genotoxicity tests, namely, the micronucleus test with mouse bone marrow and Vicia faba, and a mutagenicity test using the Ames Salmonella assay. MATERIALS AND METHODS: The bacterial reverse mutation test (Salmonella typhimurium strains TA97, TA98, TA100, TA102, and TA1535), the Vicia root tip and mouse micronucleus tests were conducted according to published protocols. RESULTS: In the range of the formicide Macex® concentrations tested from 0.06 to 1.0 g L⁻¹ (or mgkg⁻¹ in the mouse test), no genotoxicity was observed in the prokaryotic or eukaryotic test organisms. However, at Macex® concentrations of 0.5 g L⁻¹ and above a significant decrease in the mitotic index (P ≤ 0.05) in the V. faba was observed. Micronucleus formation was likewise increased in the test organism at concentrations starting at 2.0 g L⁻¹. CONCLUSIONS: These data allow us to classify this natural formicide preparation as a product with no geno-environmental-impact when applied at recommended concentrations.

Environmental impact of industrial sludge stabilization/solidification products: chemical or ecotoxicological hazard evaluation?

Nowadays, the classification of industrial solid wastes is not based on risk analysis, thus the aim of this study was to compare the toxicity classifications based on the chemical and ecotoxicological characterization of four industrial sludges submitted to a two-step stabilization/solidification (S/S) processes. To classify S/S products as hazardous or non-hazardous, values cited in Brazilian chemical waste regulations were adopted and compared to the results obtained with a battery of biotests (bacteria, alga and daphnids) which were carried out with soluble and leaching fractions. In some cases the hazardous potential of industrial sludge was underestimated, since the S/S products obtained from the metal-mechanics and automotive sludges were chemically classified as non-hazardous (but non-inert) when the ecotoxicity tests showed toxicity values for leaching and soluble fractions. In other cases, the environmental impact was overestimated, since the S/S products of the textile sludges were chemically classified as non-inert (but non-hazardous) while ecotoxicity tests did not reveal any effects on bacteria, daphnids and algae. From the results of the chemical and ecotoxicological analyses we concluded that: (i) current regulations related to solid waste classification based on leachability and solubility tests do not ensure reliable results with respect to environmental protection; (ii) the two-step process was very effective in terms of metal immobilization, even at higher metal-concentrations. Considering that S/S products will be subject to environmental conditions, it is of great interest to test the ecotoxicity potential of the contaminants release from these products with a view to avoiding environmental impact given the unreliability of ecotoxicological estimations originating from chemical analysis.