Phytoremediation Effect Research Articles

Phytoremediation of batik industry wastewater using water hyacinth plant as a medium for maintaining Cyprinus Carpio L.

Batik is one of Indonesia's cultural heritage that has been recognized internationally. Currently, public demand for batik continues to increase, increasing the production of the batik industry in Banten and will be the impact of increasing batik liquid waste. The results of batik production waste are usually directly disposed of through public water channels without being treated first. This condition can cause environmental pollution that will disrupt the sustainability of aquatic ecosystems. The purpose of this study was to determine the effect of phytoremediation of batik industrial wastewater on the lethality and structure of Cyprinus Carpio L. scales. This study used a completely randomized design with 5 treatments and 3 repetitions. The treatment used was the maintenance of Cyprinus Carpio L. in the wastewater from the phytoremediation batik industry with concentrations of 0%, 5%, 10%, 20%, and 40%. The results showed that phytoremediation using water hyacinth plants reduced the BOD and COD content of batik waste. Phytoremediation of batik waste affects the lethality of Cyprinus Carpio L. and the structure of the scales. At concentrations of 20% and 40%, the highest average percentage of lethality is 60% death. Fish mortality is characterized by changes in behavior such as movement activity, body balance, and color morphology. The concentration of the batik industry wastewater also affects the amount of lethality and the sublethal effect of Cyprinus Carpio L. The attachment of the waste indicates the sublethal effect to the scales, the highest concentration of which is 20% and 40%, respectively.

Active Botanical Biofiltration in Built Environment to Maintain Indoor Air Quality

The implementation of sustainable solutions for maintaining indoor air quality has become a particular concern to the building community. Research on green technologies for indoor air has highlighted the potential of active botanical biofiltration (ABB) systems, where the air is circulated through the plant root zone as well as the growing medium for maximum phytoremediation effect. ABB has been found beneficial for pollutant removal along with the potential for increasing humidity and air cooling. Assessment in laboratory condition revealed the removal efficiency of ABB systems ranged from 54 to 85% for total suspended particulate matters where gaseous pollutants such as formaldehyde and toluene removal efficiencies were 90% and over 33%, respectively, in real environment. Moreover, the esthetic value of ABB acts as an added benefit for positive mental effects. However, very limited data is available to date that demonstrates the pollutant removal efficiency of ABB systems in realistic indoor environments, and the mechanisms behind this emerging technology are still poorly understood. The purpose of this mini review study is to present a quantitative assessment of the recent advancement of ABB systems and indoor air quality. Finally, the limitations of ABB systems and research gaps are highlighted for future improvement.

Histological and proteome analyses of Microbacterium foliorum-mediated decrease in arsenic toxicity in Melastoma malabathricum.

Arsenic (As) is an increasing threat across the globe, widely known as a non-threshold carcinogen, and it is reaching harmful values in several areas of the world. In this study, the effect of plant growth promoting bacteria (Microbacterium foliorum) on inorganic arsenic (Arsenate) phytoremediation by Melastoma malabathricum plants was investigated through histological analysis and proteome profiling of the M. malabathricum plants. Two-dimensional gel electrophoresis and transmission electron microscopy were used to conduct the proteome and histological analysis. When arsenic-treated cells were compared to untreated cells, substantial changes were found (1) severely altered the morphology of the cells, intensely disturbed; (2) the cell wall was thicker; (3) drastically changed the cytoplasm, the cells were polygonal in shape, different in size (scattered), and relatively dense. Compared to the control group, the ultra-structure of the root cells of the control group revealed intact cytoplasm, vacuole, and cell wall under exposure to As + bacteria that had a minor effect on the cell form. To further understand As + bacteria interaction, proteome profiling of the root cell was analyzed. The As-induced oxidative stress enrichment was confirmed by the up-regulation of tubulin, nucleoside diphosphate kinase, and major allergen during As + bacteria exposure It was observed that the profusion of proteins involved in defence, protein biogenesis, signaling, photosynthesis, nucleoside and energy metabolism was greater in As + bacteria as compared to the rooting out of As only. Overall, it can be obviously seen that the current study demonstrates the effectiveness of phytoremediation by M. foliorum on proteins involved and responsive pathways in dealing with As toxicity in M. malabathricum plant.

Effect of Phytoremediation on Compression Characteristics of Silty Clayey Sand Contaminated with Crude Oil

Effect of Phytoremediation on Compression Characteristics of Silty Clayey Sand Contaminated with Crude Oil

APPLICATION OF A MODEL INSTALLATION FOR EVALUATION OF EFFICIENCY OF PHYTOREMEDIATION METHODS OF SURFACE WASTEWATER TREATMENT

The article provides an assessment of the phytoremediation method as a promising direction of passive protection of soils and water bodies from pollution by surface waste waters, especially those contaminated as a result of fire extinguishing processes. Particular attention is paid to the danger of contamination with anionic surfactants. Natural methods of surface runoff purification have been analyzed, the efficiency of wastewater treatment in troughs with the use of industrial waste has been investigated. The prospects of using environmentally friendly plastic waste (PET, polypropylene, etc.) for the creation of artificial bioengineering structures are noted. An experimental model installation was developed and installed for testing and evaluating the effectiveness of various methods and methods of phytoremediation. Based on the results of experimental studies, a method is proposed for assessing the effectiveness of using various types of filtering nozzles in troughs for purifying wastewater and various types of vegetation in a research model installation. The effectiveness of phytoremediation to reduce the harmful effect of anionic surfactants on the composition of wastewater after the use of foaming agents in extinguishing fires has been analyzed. An analysis of the use of a filter nozzle from defibrated PET containers showed an increase in the efficiency of phytoremediation processes.

Effect of Phytoremediation on Geotechnical Characteristics of Oil Contaminated Sands

ABSTRACT The environmental contaminations occurred by exploration, drilling, extraction, transportation and storage of different substances for using in industries have serious effects on soils and their properties. This research examined the effects of phytoremediation on the removal of total petroleum hydrocarbons (TPHs) and geotechnical properties of a silty clayey sand contaminated by 3%, 5%, and 7% crude oil. Ophiopogon japonicus and Platycladus orientalis were two types of plants used to determine the phytoremediation effects within 30 and 60 days of operation. The scanning electron microscopy (SEM) images indicated that with increase in crude oil content at 0, 30, and 60 days of investigations, the soil particles become more flocculated. Comparison of the soil samples that experienced phytoremediation and without phytoremediation showed that flocculation of the soil particles became less during phytoremediation process. Use of Platycladus orientalis reduced soil flocculation more compared to Ophiopogon japonicus. The test results also showed that the TPHs removal rate using Platycladus orientalis was more than Ophiopogon japonicus. The addition of more crude oil contents caused enhancement of permeability while liquid limit, plastic limit, maximum dry density, optimum moisture content and CBR decreased. Investigation of the geotechnical properties of soil at different crude oil contents in 30 and 60 days of phytoremediation revealed that soil samples that experienced phytoremediation had more CBR and lower permeability compared to other ones without phytoremediation. It was also observed that upon more days of phytoremediation the liquid limit, plastic limit, optimum moisture content and permeability increased while the maximum dry density decreased. Using Platycladus orientalis compared to Ophiopogon japonicus yielded higher liquid limit, plastic limit, maximum dry density, and CBR along with lower optimum moisture content and permeability.

Enhancement of EAPR Treatment Using Double Aeration System and Uptake by Pakcoy (<i>Brassica rapa subsp. chinensis</i>)

This study was aimed at investigating the effect of electro-assisted and double aeration (EAPR-DA) system to enhance the lead removal in water and uptake by Pakcoy (Brassica rapa subsp. Chinensis). Variable regimes were created by 2 V of constant DC voltage using 2D stainless steel cathode-pot and Ti anode electrode, and aeration level of 10 L/min. The effectiveness of EAPR-DA, EAPR, phyto-aeration, and phytoremediation on the treatment was compared and evaluated by measuring the decrease of lead concentration in the water and accumulated in the plant using flame Atomic Absorption Spectroscopy. Plant stress was evaluated by phytomorphology changed and measurement chlorophyll content using UV-Vis Spectroscopy after the acetone extraction. The results showed that the EAPR-DA system using Pakcoy has a great ability to decrease the lead concentration in water compared with the EAPR, phyto-aeration, and phytoremediation. The removal ability in each reactor was 82.5%, 78.75%, 72.5%, and 61.875% respectively for EAPR-DA, EAPR, phytoremediation. and phyto-aeration. Excessive aeration in the root zone might inhibit lead adsorption by a plant in the phyto-aeration system. In general, the accumulation of lead in plant growth hydroponically has a large concentration in the roots compared to the shoot except for the EAPR-DA system which high adsorption of lead concentration in the shoot part. The BC (1.13) and TF (1.97) value of the EAPR-DA system was higher than the other systems, showing aeration can enhance high adsorption of lead in the root and then transported it into the shoots part. High chlorophyll total (54.89±14.31 mg/mL) and low chlorophyll a/b ratio (1.21±0.38) in the plant under the EAPR-DA system showed that the double aeration in the electro-assisted system encourages the high tolerance of the plant to the lead concentration.

Reduksi Kadar Phospat Limbah Cair Rumah Sakit Menggunakan Bakung Putih (Crinum asiaticum Linn.) (Studi Kasus: RSUD dr. Soehadi Prijonegoro Kabupaten Sragen)

RSUD dr. Soehadi Prijonegoro Sragen produces liquid waste containing microorganisms, toxic and radioactive chemicals. The results of the laboratory examination showed that the liquid waste level always exceeded the quality standard, namely the parameter of phosphate. The phosphate level in September 2013 was 4.80 mg / L, while in December 2013 the concentration was 2.60 mg / L, so additional treatment is needed, one of which is phytoremediation using white daffodils (Crinum asiaticum Linn.). This research method is an experimental research design with pre-post Test with Control Group Design where the wastewater will pass through a wet tank containing white lily plants with a residence time of 24 hours/day and a treatment rate of 1100 liters/day. Th research aimed to determine the effect of phytoremediation of white daffodils on the reduction of phosphate levels and the average percentage of its reduction. The results of this study in the ninth and tenth sample collection met the quality standards of 1.99 mg / L and 1.89 mg / L. Phytoremediation of white daffodils (Crinum asiaticum linn.) may reduce phosphate levels by 45.59%.

Effect of phytoremediation on the shear strength characteristics of silty clayey sand

Pollution of the environment by crude oil is a global problem that changes the geotechnical properties of soil, including its shear strength. In this study, the effects of phytoremediation of soil contaminated with crude oil have been investigated using Ophiopogon japonicus and Platycladus orientalis. The results of phytoremediation were tested at 30 and 60 days of treatment. The results were compared with samples that had not undergone phytoremediation. The soil shear strength parameters were determined using unconsolidated undrained triaxial compression tests at confining pressures of 50, 100, and 150 kPa. The results showed that an increase in the crude oil content led to a decrease in deviatoric stress at failure associated to an axial strain level of 20%. The deviatoric stress in the treated samples was about 15% higher than the samples without phytoremediation. The internal friction angle and cohesion decreased as the crude oil content increased. This decrease was less in the remediated samples, especially those exposed to P. orientalis. The results of the triaxial compression tests revealed the positive effect of phytoremediation in reducing the negative effects of crude oil on the soil shear strength characteristics. SEM images of the contaminated soil samples showed that soil flocculation initially increased with an increase in the crude oil content and time and then decreased subsequent to the application of phytoremediation.

Phytoremediation potential of flowering plants in relation to lead

This paper deals with the study of the phytoremediation potential of flowering plants in relation to lead ions under laboratory conditions. The test cultures were phacelia tansy (Phacelia tanacetifolia Benth.), white mustard (Sinapis alba L.), small-flowered marigolds (Tagеtes patula L.) and a mixture of cereal grasses consisting of red fescue 40% (Festuca rubra L.), perennial ryegrass 50% (Lolium perenne L.) and meadow bluegrass 10% (Poa pratensis L.). Under the experimental conditions lead ions in concentrations of 2 and 10 MPC were introduced into the soil sampled from the territory of agricultural lands (leached medium-thick heavy loamy chernozem with a high content of humus, mobile phosphorus and exchangeable potassium, low content of nitrate nitrogen, bulk and mobile forms of lead). It has been established that all representatives of weeds, ornamental and green manure plants selected as test crops are capable, to one degree or another, of accumulating lead ions from soils and therefore can function as phytoremediators of agricultural lands intended for organic farming. The ability to accumulate lead ions increases in the following order: phacelia marigolds mustard a mixture of cereal grasses. The maximum effect of phytoremediation of the soil was revealed in the variant with a cereal mixture (the content of lead ions in the soil with the introduction of 2 MPC decreases by 32,8%, with the introduction of 10 MPC by 23,6%).

Оксидоредуктазна активність ґрунтів в умовах нафтового забруднення та фіторемедіації

The effect of oil pollution and phytoremediation with Zea mays L. and Vicia faba var. Minor on soil oxidoreductase activity was investigated. The experiment was carried out under field conditions. Soil was artificially contaminated by oil at rate 4.2 % (50 ml of oil per 1 kg of soil). Soil sampling was performed at 10th, 22th, 30th days (the firs experiment stage) before sowing plants and seedlings emergence and at 65th, 95th days (second experiment stage) with plants vegetation. Results showed that soil catalase activity (CA) was reduced during the first experiment stage and increased later under oil contamination conditions compared to control. The reduction of soil enzyme activity can be related to inhibition of soil microbial activity by hydrocarbons toxic influence. On the other hand recovery of enzyme activity can be due to decrease of toxicity of soil conditions over time. A two-way analysis of variance yielded a main effect for the phytoremediation (p<0,01), such that the average CA was significantly higher for soil with plants than for unplanted soil. The interaction effect was significant between oil contamination and phytoremediation with Z. mays (p<0,01), indicating that the plants’ effect was greater in the oil contamination condition than without oil contamination. Soil dehydrogenase activity (DA) in oil contamination conditions decreased during all experiment compared to control. A main effect of phytoremediation on DA was significant (p<0,05), the interaction effect between oil contamination and phytoremediation was significant too (p<0,05). Interaction effect between oil contamination and phytoremediation can indicate improving conditions for microbial activity in the rooting zone. The plant’s exudates may create more feasible conditions for utilisation of carbohydrates by microorganisms. Polyphenol oxidase (PPOA) activity decreased on the 95th day in oil contaminated soil compared to control. PPOA was stimulated by Z. mays and V. faba plants in soil without oil, and only by Z. mays in oil contaminated soil. Soil phytoremediation treatment was related to the increase of enzyme activity. Such plants can be feasible for oil contaminated soil remediation.

Heavy Metals and Plant Physiology: Tolerance Mechanisms and Phytoremediation Strategies

Heavy metals such as cadmium, lead, and mercury are pervasive environmental pollutants resulting from industrial activities, mining, and agricultural practices. These metals pose significant threats to plant health by disrupting physiological processes, leading to reduced growth and productivity. Plants, however, have evolved various mechanisms to tolerate and detoxify heavy metals, making them potential candidates for phytoremediation—a green technology for environmental cleanup. This review explores the sources and types of heavy metals, their impact on plant physiology, and the intricate mechanisms plants employ for heavy metal tolerance. Additionally, it examines the current and potential future applications of phytoremediation strategies, including phytoextraction, phytostabilization, phytovolatilization, and rhizofiltration. Through case studies and examples, the review highlights successful applications and the challenges associated with phytoremediation. It concludes with a discussion on future perspectives, emphasizing advances in genetic engineering and the integration of sustainable practices and policies to enhance the effectiveness and adoption of phytoremediation.

Effect of endophytic-assisted phytoremediation on plant growth and chromium (Cr) toxicity reduction in contaminated soil

This study focused on phytoremediation of chromium (Cr) through endophytic bacteria. Four endophytic bacteria i.e. Pseudomonas putida (CEN2), Pseudomonas aeruginosa (CEN3), Acinetobacter baumanni (CEN4), and Pseudomonas aeruginosa (CEN5) were selected for phytoremediation experiments to investigate its effects on plant growth and Cr uptake. Phytoremediation experiment was carried out by using one hyper accumulator (Brassica napus) and one non-hyper accumulator plant (Coriandrum sativum), grown in agricultural soil amended with three different concentrations 50 ppm, 100 ppm and 200 ppm of Cr for 60 days. In Brassica napus, endophytic consortia showed maximum root, shoot elongation and vigour index at all concentrations. In Coriandrum sativum CEN5 strain showed maximum root, shoot length and vigour index. Brassica napus with consortia produced maximum fresh and dry biomass as compared to the control treatments. Therefore, endophytic-assisted phytoremediation could be a promising tool for mitigating heavy metals toxicity from polluted soil without any negative effects on plant growth.

Effect of endophytic-assisted phytoremediation on plant growth and chromium (Cr) toxicity reduction in contaminated soil

Effect of endophytic-assisted phytoremediation on plant growth and chromium (Cr) toxicity reduction in contaminated soil

Remedial capacity of diclosulam by cover plants in different edaphoclimatic conditions

Pre-emergent herbicides have been developed for their long residual effect; however, they can make sensitive successor cultures unfeasible. Waste remediation techniques are needed for sustainable agricultural systems; for this, the edaphoclimatic asymmetries in the country must be considered. This study aimed to evaluate the remedial capacity of the herbicide diclosulam by covering crops under different edaphoclimatic conditions. Treatments were arranged in an n × 2 factorial scheme, the first factor being the number of plant species in each location and the second being the presence or absence of diclosulam in the soil. The physiological and growth characteristics of 15 potential phytoremediation species were evaluated. Herbicide residues in the environment were positively correlated with the soil pH; organic matter, aluminum, and silt contents; and aluminum saturation. The effectiveness of phytoremediation varied between species and between regions. Plant species suitable for efficient phytoremidation systems of diclosulam residues were Canavalia ensiformis for Couto Magalhães de Minas, Cajanus cajan and Canavalia ensiformis for Diamantina, Raphanus sativus for Erechim and Cajanus cajan for São João Evangelista.

Evaluation of phytoremediation effects of chicken manure, urea and lemongrass on remediating a lead contaminated soil in Kabwe, Zambia

High levels of lead (Pb) in the soil is a serious issue in the city of Kabwe, Zambia. Phytoremediation is an effective approach to revive the life-supporting functions of the soils. Locally available soil amendments, such as chicken manure, can strengthen phytoremediation. This study aims to find an appropriate combination of a locally available Pb hyperaccumulator, lemongrass (Cymbopogon citratus (DC.) Stapf.), and soil amendments, to minimize the Pb pollution. After a short-term (78 day) pot experiment with lemongrass and three soil amendments (chicken manure, biochar of chicken manure, and urea) on a Pb-contaminated soil in Kabwe, an edible crop, dent corn (Zea mays var. indentata (Sturtev.) L.H.Bailey), was grown for two weeks. Chicken manure combined with lemongrass had the most beneficial impact, reducing the Pb level in dent corn by 19%, compared to the Pb in dent corn grown on the control soil. By growing lemongrass in the Kabwe soil with chicken manure, the exchangeable soil Pb was reduced by 70%. The growth of lemongrass without chicken manure reduced the exchangeable soil Pb by 20%. In conclusion, lemongrass successfully reduced Pb levels, in combination with chicken manure. Soil amendments must be chosen carefully by considering the soil properties and environmental conditions for an optimized Pb reduction.

Impact of O3 on the phytoremediation effect of Celosia argentea in decontaminating Cd

Elevated atmospheric O3 can inhibit the growth rate of various plants and increase metal content in their tissues owing to the oxidative damage, thereby affecting their phytoremediation efficiency. In this study, a series of O3 fumigation treatments were designed to evaluate the dry weight, Cd content, and transpiration rate responses of Celosia argentea to different levels of O3 (40, 50, 55, 60, 65, and 80 ppb). The dry weight of C. argentea decreased as the atmospheric O3 level increased, and the Cd concentration of the plant leaves increased until the level of O3 reached 60 ppb before decreasing slightly. The variations in the transpiration rate followed a similar trend to the Cd content under different O3 levels. The phytoremediation efficiency of C. argentea increased with O3 fumigation at low (50 ppb) and moderate (55 and 60 ppb) levels, and significantly decreased at the highest level. The regression curves indicated that the plant species treated with 52 ppb of O3 exhibited the highest Cd accumulation capacity. Overall, the phytoremediation effect of C. argentea cultivated in Cd-polluted soil might be improved under the high-O3 conditions. This result might help to choose suitable plants for soil remediation in future atmospheric environment.

Influence of elevated atmospheric CO2 levels on phytoremediation effect of Festuca arundinacea intercropped with Echinochloa caudata

Atmospheric CO2 levels have been increasing with increasing industrialization. Studies have shown the growth response of various plant species to climate change and increasing CO2 levels, but variations in phytoremediation caused by elevated CO2 levels, especially in intercropping systems, have rarely been reported. The current study therefore revealed variations in the phytoremediation effect of Festuca arundinacea intercropped with Echinochloa caudata, a pernicious annual weed, exposed to various CO2 levels (280, 400, and 550 ppm). The biomass yield and Cd uptake capacity of monocultured F. arundinacea were found to increase with increasing atmospheric CO2 level, highlighting the promoted phytoremediation efficiency of this species under elevated CO2 levels. Elevated CO2 levels also significantly increased the dry weight of monocultured E. caudata but did not change the Cd content in various parts of the plant. However, the intercropping system decreased the biomass yield of belowground and aerial parts of F. arundinacea under all treatments, since E. caudata competed with it for water and nutrients. The weight reduction of F. arundinacea in the intercropping system increased with increasing CO2 level, because elevated CO2 significantly increased the competitiveness of the weed. Therefore, the Cd phytoremediation efficiency of F. arundinacea intercropped with E. caudata exposed to 280, 400, and 550 ppm CO2 decreased by 46.1%, 81.5%, and 215.0%, respectively, as evidenced by the decreased dry weight of F. arundinacea. Therefore, elevated CO2 levels could decrease the phytoremediation effect of F. arundinacea in fields where weed growth is unavoidable.

Novel Integration of Geopolymer Pavers, Silva Cells and Poplar Trees for In-Situ Treatment of Car-Wash Wastewater

This paper presents an eco-friendly, low-impact development (LID) approach, developed and implemented at a car wash site for a cleaner and greener environment. In this approach, the contaminated water discharged after car washing is treated as it is directed through an engineered, ecology-based water-management design. The design involves poplar (Populus deltoides) trees, Silva Cells®, and Fly-ash based Geopolymer concrete pavers working collectively to minimize the percolation of contaminants into the soil. In this novel system, each component has a vital role. For instance, the extensive roots of the poplar trees enable water filtration owing to phytoremediation effect; while the Silva Cells® promote stormwater management, planting of poplar trees and serve as a foundation for paver blocks. Lastly, the paver blocks made from industrial waste allow it to withstand urban load and infiltrate water runoff, thereby reducing runoff quantities. To evaluate the efficacy of contaminant uptake by this system, pH, electrical conductivity and turbidity, which are indicators of water quality levels, were monitored pre- and post-treatment. The percentage change in total dissolved solids indicates the potential of this treatment system for effective treatment of the contaminated car wash water.

Hybrid technologies for remediation of highly Pb contaminated soil: sewage sludge application and phytoremediation

Phytoremediation techniques and stabilization of heavy metals with municipal sewage sludge (SW) in soils are usually studied separately. We aimed to verify the potential of the combined use of phytoextraction method and metal stabilization with SW in the recovery of soil with high Pb content (total = 28,650 mg kg−1 and exchangeable = 1,120 mg kg−1) and to verify the effect of the association of these two techniques on the Pb fractions in the soil (stabilization). We have tested five doses of SW (0; 13.4; 26.7; 53.4; 106.8 Mg ha−1) and three cultivation conditions (uncultivated, black oats and forage turnip). The SW application in soil with a high Pb content favored the nutrition and growth of the plants (shoots and roots) and promoted an increase in the Pb absorption, a desirable combination in phytoextraction. The SW application and the cultivation of plants had a positive effect on the stabilization of Pb in the soil. It was verified decrease of the exchangeable fraction and increase precipitated and adsorbed by inner-sphere at the edges of the kaolinite and gibbsite. The combined use of SW and phytoremediation is very promising and should be tested on soils with moderate levels of heavy metals. Novelty statement: We believe that the study presents a more comprehensive methodology to assess and to recover soils highly contaminated with heavy metals. Conditions of the high toxicity of heavy metals in the soil compromise the growth of plants and limit the effectiveness of phytoremediation. We aimed to verify the potential of the combined use of phytoextraction and stabilization with sewage sludge in the recovery of soil with a high Pb content and to verify the effect of the association of these two techniques on the Pb fractions in the soil (stabilization). Often, the simple evaluation of the reduction in total Pb contents with phytoremediation is not sufficient to describe the magnitude of soil decontamination. The ideal is also to determine the different forms of Pb (such as: soluble; exchangeable; precipitate; complexed in organic matter; inner-sphere adsorption in Fe and Mn oxides; inner-sphere adsorption in gibbsite and kaolinite; residue) in soil before and after the recovery techniques to access the possible migration to more stable environmental Pb fractions.