Anaerobic ammonium oxidation by Nitrosomonas spp. and anammox bacteria in a sequencing batch reactor

A sequencing batch reactor (SBR) was inoculated with mixed nitrifying bacteria from an anoxic tank at the conventional activated sludge wastewater treatment plant in Nongkhaem, Bangkok, Thailand. This enriched nitrifying culture was maintained under anaerobic conditions using ammonium (NH(4)(+)) as an electron donor and nitrite (NO(2)(-)) as an electron acceptor. Autotrophic ammonium oxidizing bacteria survived under these conditions. The enrichment period for anammox culture was over 100 days. Both ammonium and nitrite conversion rates were proportional to the biomass of ammonium oxidizing bacteria; rates were 0.08 g N/gV SS/d and 0.05 g N/g VSS/d for ammonium and nitrite, respectively, in a culture maintained for 3 months at 42 mg N/L ammonium. The nitrogen transformation rate at a ratio of NH(4)(+)-N to NO(2)(-)-N of 1:1.38 was faster, and effluent nitrogen levels were lower, than at ratios of 1:0.671, 1:2.18, and 1:3.05. Fluorescent in situ hybridization (FISH) was used to identify specific autotrophic ammonium oxidizing bacteria (Nitrosomonas spp., Candidatus Brocadia anammoxidans, and Candidatus Kuenenia stuttgartiensis). The ammonium oxidizing culture maintained at 42 mg N/L ammonium was enriched for Nitrosomonas spp. (30%) over Candidati B. anammoxidans and K. stuttgartiensis (2.1%) while the culture maintained at 210 mg N/L ammonium was dominated by Candidati B. anammoxidans and K. stuttgartiensis (85.6%). The specific nitrogen removal rate of anammox bacteria (0.6 g N/g anammox VSS/d) was significantly higher than that of ammonium oxidizing bacteria (0.4 g N/g Nitrosomonas VSS/d). Anammox bacteria removed up to 979 mg N/L/d of total nitrogen (ammonium:nitrite concentrations, 397:582 mg N/L). These results suggest significant promise of this approach for application to wastewater with high nitrogen but low carbon content, such as that found in Bangkok.     

Potential nitrification and denitrification on different surfaces in a constructed treatment wetland

Improved understanding of the importance of different surfaces in supporting attached nitrifying and denitrifying bacteria is essential if we are to optimize the N removal capacity of treatment wetlands. The aim of this study was therefore to examine the nitrifying and denitrifying capacity of different surfaces in a constructed treatment wetland and to assess the relative importance of these surfaces for overall N removal in the wetland. Intact sediment cores, old pine and spruce twigs, shoots of Eurasian watermilfoil (Myriophyllum spicatum L.), and filamentous macro-algae were collected in July and November 1999 in two basins of the wetland system. One of the basins had been constructed on land that contained lots of wood debris, particularly twigs of coniferous trees. Potential nitrification was measured using the isotope-dilution technique, and potential denitrification was determined using the acetylene-inhibition technique in laboratory microcosm incubations. Nitrification rates were highest on the twigs. These rates were three and 100 times higher than in the sediment and on Eurasian watermilfoil, respectively. Potential denitrification rates were highest in the sediment. These rates were three times higher than on the twigs and 40 times higher than on Eurasian watermilfoil. The distribution of denitrifying bacteria was most likely due to the availability of organic material, with higher denitrification rates in the sediment than on surfaces in the water column. Our results indicate that denitrification, and particularly nitrification, in treatment wetlands could be significantly increased by addition of surfaces such as twigs.     

Links among nitrification, nitrifier communities, and edaphic properties in contrasting soils receiving dairy slurry

Soil biotic and abiotic factors strongly influence nitrogen (N) availability and increases in nitrification rates associated with the application of manure. In this study, we examine the effects of edaphic properties and a dairy (Bos taurus) slurry amendment on N availability, nitrification rates and nitrifier communities. Soils of variable texture and clay mineralogy were collected from six USDA-ARS research sites and incubated for 28 d with and without dairy slurry applied at a rate of ~300 kg N ha(-1). Periodically, subsamples were removed for analyses of 2 M KCl extractable N and nitrification potential, as well as gene copy numbers of ammonia-oxidizing bacteria (AOB) and archaea (AOA). Spearman coefficients for nitrification potentials and AOB copy number were positively correlated with total soil C, total soil N, cation exchange capacity, and clay mineralogy in treatments with and without slurry application. Our data show that the quantity and type of clay minerals present in a soil affect nitrifier populations, nitrification rates, and the release of inorganic N. Nitrogen mineralization, nitrification potentials, and edaphic properties were positively correlated with AOB gene copy numbers. On average, AOA gene copy numbers were an order of magnitude lower than those of AOB across the six soils and did not increase with slurry application. Our research suggests that the two nitrifier communities overlap but have different optimum environmental conditions for growth and activity that are partly determined by the interaction of manure-derived ammonium with soil properties.     

Nitrous oxide emissions from wastewater treatment and water reclamation plants in southern California

Nitrous oxide (N?O) is a long-lived and potent greenhouse gas produced during microbial nitrification and denitrification. In developed countries, centralized water reclamation plants often use these processes for N removal before effluent is used for irrigation or discharged to surface water, thus making this treatment a potentially large source of N?O in urban areas. In the arid but densely populated southwestern United States, water reclamation for irrigation is an important alternative to long-distance water importation. We measured N?O concentrations and fluxes from several wastewater treatment processes in urban southern California. We found that N removal during water reclamation may lead to in situ N?O emission rates that are three or more times greater than traditional treatment processes (C oxidation only). In the water reclamation plants tested, N?O production was a greater percentage of total N removed (1.2%) than traditional treatment processes (C oxidation only) (0.4%). We also measured stable isotope ratios (δN and δO) of emitted N?O and found distinct δN signatures of N?O from denitrification (0.0 ± 4.0 ‰) and nitrification reactors (-24.5 ± 2.2 ‰), respectively. These isotope data confirm that both nitrification and denitrification contribute to N?O emissions within the same treatment plant. Our estimates indicate that N?O emissions from biological N removal for water reclamation may be several orders of magnitude greater than N?O emissions from agricultural activities in highly urbanized southern California. Our results suggest that wastewater treatment that includes biological nitrogen removal can significantly increase urban N?O emissions.     

ASM2G在污水处理中的研究与应用

针对用静态模型常规设计在设计效果与模拟分析上的不足,作者在研究动态机理模型ASM2d的基础上开发了污水处理仿真程序ASM2G,以分析污水生物处理,并进行模拟分析与辅助设计.本文首先介绍了此自编程序的机理模型ASM2d;其次说明了ASM2G的模拟过程;最后,通过对实际污水处理厂的模拟比较,说明了ASM2G在模拟分析上的优势,同时也反映了ASM2d能够较好地反映污水处理的运行状况,是一个较成熟的动态机理模型.文章试图为找到一种经济有效的设计方法提供一定的参考.     

Biological treatment of tannery wastewater in the presence of chromium

Experiments were carried out to determine the feasibility of treating tannery wastewater containing chromium, an inhibiting compound, with sequencing batch reactors (SBR). The maximum chromium concentration tolerated by microorganisms was determined through aerobic and anoxic batch experiments, and the biomass inhibition process was analyzed in a lab scale reactor at increasing chromium concentrations. The results obtained, in batch experiments and in the SBR reactor, have demonstrated that chromium addition had less influence on the denitrification bacteria than on the nitrification bacteria. In addition, it was observed that nitrification and denitrification rates, at the same chromium concentration, were higher in the SBR reactor than in batch experiments with unacclimated biomass. Experimental results confirm that sequencing batch reactors are able to produce a more resistant biomass, which acclimates quickly to inhibiting conditions. A large amount of chromium was found in the sludge from the reactor, while the effluent was devoid of the inhibiting metal.     

Analysis of the nitrifying bacterial community in BioCube sponge media using fluorescent in situ hybridization (FISH) and microelectrodes

There is growing interest in the development of more cost-effective and retrofit technologies for the upgrade and expansion of existing wastewater treatment plants with extreme space constraints. A free-floating sponge media (BioCube) process, using a 24L lab scale reactor, was operated to study the nitrification profiles and microbial community. The COD removal efficiencies were maintained, at an average of 95%, with the mixed liquor suspended solids (MLSS) inside the BioCube sponge media maintained at 12,688mg/L. The nitrification removal efficiencies were between 92% and 100%, with an average value of 99%. From the results of microelectrode measurements, the ammonium ion concentration was found to rapidly decrease from the surface of the BioCube sponge media to a depth of 2mm due to chemical reactions carried out by ammonia oxidizing bacteria (AOB) species. Multi-fluorescence in situ hybridization (FISH) has been used to investigate the spatial distributions of various microbial activities within reactors. Microbial communities were targeted using different oligonucleotide probes specific to AOB and nitrite oxidizing bacteria (NOB). There were a large number of AOB populations, but these were not uniformly distributed in the biofilm compared to the NOB populations.     

焦化废水生物脱氮工艺的探讨

焦化废水是一种氨氮和有机物浓度较高的难生化降解有机废水。随着排放指标的日益严格,出现了很多焦化废水的处理新技术,而焦化废水的生物脱氮技术的发展是其中非常重要的一个方面。本文以生物脱氮硝化／反硝化反应的反应途径为线索,系统分析了国内外近年来在焦化废水生物脱氮方面的研究进展,并简要介绍了国外一些生物脱氮的新技术,包括SHARON工艺、OLAND工艺和ANAMMOX工艺。     

EFFECTS OF ADVANCED WASTEWATER TREATMENT ON THE QUALITY OF WHITE RIVER,INDIANA1

ABSTRACT: In 1983, the City of Indianapolis, Indiana, completed construction of advanced wastewater treatment (AWT) systems to enlarge and upgrade its existing Belmont Road and South port Road secondary treatment plants. A nonparametric statistical procedure, a modified form of the Wilcoxon-Mann-Whitney rank-sum test, was used to test for trends in water quality at two upstream and two downstream sites on White River and at the two treatment plants. Results comparing the pre- (1978–1980) and post- (1983–1986) AWT periods show statistically significant improvements in the quality of the treated effluent and of the White River downstream from the plants. Water quality at sites upstream from the city was relatively constant during the period of study. Total ammonia (as N) decreased 14.6 mg/L and BOD₅ (five-day biochemical oxygen demand) decreased 10 to 19 mg/L in the two effluents. Total ammonia in the river downstream from the plants decreased 0.8 to 1.9 mg/L and BOD₅ decreased 2.3 to 2.5 mg/L. Nitrate (as N) increased 14.5 mg/L in the plant effluents and 2.0 to 2.4 mg/L in the river because of in-plant nitrification. Dissolved oxygen concentration in the river increased about 3 mg/L because of reduced oxygen demand for nitrification and biochemical oxidation processes.     

Temperature and wetland plant species effects on wastewater treatment and root zone oxidation

Constructed wetlands are widely used for wastewater treatment, but there is little information on processes affecting their performance in cold climates, effects of plants on seasonal performance, or plant selection for cold regions. We evaluated the effects of three plant species on seasonal removal of dissolved organic matter (OM) (measured by chemical oxygen demand and dissolved organic carbon) and root zone oxidation status (measured by redox potential [Eh] and sulfate [SO4(2-)]) in subsurface-flow wetland (SSW) microcosms. A series of 20-d incubations of simulated wastewater was conducted during a 28-mo greenhouse study at temperatures from 4 to 24 degrees C. Presence and species of plants strongly affected seasonal differences in OM removal and root zone oxidation. All plants enhanced OM removal compared with unplanted controls, but plant effects and differences among species were much greater at 4 degrees C, during dormancy, than at 24 degrees C, during the growing season. Low temperatures were associated with decreased OM removal in unplanted controls and broadleaf cattail (Typha latifolia L.) microcosms and with increased removal in beaked sedge (Carex rostrata Stokes) and hardstem bulrush [Schoenoplectus acutus (Muhl. ex Bigelow) A. & D. L?ve var. acutus] microcosms. Differences in OM removal corresponded to species' apparent abilities to increase root zone oxygen supply. Sedge and bulrush significantly raised Eh values and SO4(2-) concentrations, particularly at 4 degrees C. These results add to evidence that SSWs can be effective in cold climates and suggest that plant species selection may be especially important to optimizing SSW performance in cold climates.     

人工湿地污水处理系统脱氮机理研究进展

本文介绍了近年来人工湿地污水处理系统脱氮机理的研究情况,阐述了人工湿地脱氮的三种途径：植物和其它生物的吸收作用、微生物的生物转化作用及氨气的挥发作用,其中微生物的生物转化作用是人工湿地主要的脱氮方式.同时对影响人工湿地脱氮效率的主要因素：温度、pH值、氧化还原电位、溶解氧、微生物可利用有机碳与硝态氮、停留时间等都作了比较详细的介绍,为进一步开展人工湿地脱氮机理的研究和优化人工湿地污水处理系统设计提供参考.     

Nitrification and denitrification rates of Everglades wetland soils along a phosphorus-impacted gradient

Little information is available on the effect of phosphorus (P) enrichment on nitrogen (N) biogeochemical cycling in wetland soil. Of particular importance are the coupled nitrification-denitrification reactions that regulate the microbially mediated loss of N from wetland systems. Soils from the northern Florida Everglades have been affected by P loading from surface waters over the past 40 years. Elevated P levels have been show to have an effect on the size and activity of the microbial pool and a decrease in the N to P ratio of the microbial biomass. The objective of the study was to determine if P enrichment in soils affected microbial activities related to nitrification and denitrification in these flooded, peat soils. Potential nitrification rates of soil and detritus were determined using constantly stirred reactors under aerobic conditions while denitrification rates were determined from anaerobic incubations of slurry. Nitrification rates showed two distinct linear phases, a slower initial rate, signifying activity of nitrifiers present, followed by a sharp increase in the NH4+ conversion rate indicative of maximum potential rates. Initial rates of nitrification were highest in the surficial detrital layer decreasing with soil depth and did not correlate to soil total P. The potential rates of nitrification were 13 times greater than the initial rates. Potential denitrification rates were highest in the detritus and 0- to 10-cm soil interval with significantly lower values in the 10- to 30-cm soil interval, significantly correlated to total P of the soil. A significant (P < 0.01) relationship was seen between potential denitrification rates and soil total P suggesting an increased rate of N removal from P-enriched regions of the northern Everglades.     

Evaluation of leachate recirculation on nitrous oxide production in the Likang Landfill,China

Landfill leachate recirculation is efficient in reducing the leachate quantity handled by a leachate treatment plant. However, after land application of leachate, nitrification and denitrification of the ammoniacal N becomes possible and the greenhouse gas nitrous oxide (N2O) is produced. Lack of information on the effects of leachate recirculation on N2O production led to a field study being conducted in the Likang Landfill (Guangzhou, China) where leachate recirculation had been practiced for 8 yr. Monthly productions and fluxes of N2O from leachate and soil were studied from June to November 2000. Environmental and chemical factors regulating N2O production were also accessed. An impermeable top liner was not used at this site; municipal solid waste was simply covered by inert soil and compacted by bulldozers. A high N2O emission rate (113 mg m-2 h-1) was detected from a leachate pond purposely formed on topsoil within the landfill boundary after leachate irrigation. A high N2O level (1.09 micrograms L-1) was detected in a gas sample emitted from topsoil 1 m from the leachate pond. Nitrous oxide production from denitrification in leachate-contaminated soil was at least 20 times higher than that from nitrification based on laboratory incubation studies. The N2O levels emitted from leachate ponds were compared with figures reported for different ecosystems and showed that the results of the present study were 68.7 to 88.6 times higher. Leachate recirculation can be a cost-effective operation in reducing the volume of leachate to be treated in landfill. However, to reduce N2O flux, leachate should be applied to underground soil rather than being irrigated and allowed to flow on topsoil.     

Infrared monitoring of dinitrotoluenes in sunflower and maize roots

Infrared microspectroscopy (IMS) is emerging as an important analytical tool for the structural analysis of biological tissue. This report describes the use of IMS coupled to a synchrotron source combined with principal components analysis (PCA) to monitor the fate and effect of dinitrotoluenes in the roots of maize and sunflower plants. Infrared imaging revealed that maize roots metabolized 2,4-dinitrotoluene (DNT) and 2,6-DNT. The DNTs and their derivative aromatic amines were predominantly associated with epidermis and xylem. Both isomers of DNT altered the structure and production of pectin and pectic polysaccharides in maize and sunflower plant roots. Infrared peaks diagnostic for aromatic amines were seen at the 5 mg L concentrations for both DNTs in maize and sunflower treated tissue. However, only infrared peaks for nitro groups, not aromatic amines, were present in the maize treated at 10 mg L For sunflower, the 10 mg L level was toxic and also produced very dark root systems making spectra difficult to obtain. Maize and sunflower seem unable to metabolize effectively at concentrations higher than about 5 mg L DNT in hydroponic solution. Based on the results of this study, IMS combined with PCA can be an effective means of determining the fate and metabolism of organic contaminants in plant tissue when isotopically labeled compounds are not available.     

Root exudation, phosphorus acquisition, and microbial diversity in the rhizosphere of white lupine as affected by phosphorus supply and atmospheric carbon dioxide concentration

White lupine (Lupinus albus L.) was used as a phosphorus (P)-efficient model plant to study the effects of elevated atmospheric CO(2) concentrations on (i) P acquisition, (ii) the related alterations in root development and rhizosphere chemistry, and (iii) the functional and structural diversity of rhizosphere microbial communities, on a P-deficient calcareous subsoil with and without soluble P fertilization. In both +P (80 mg P kg(-1)) and -P treatments (no added P), elevated CO(2) (800 micromol mol(-1)) increased shoot biomass production by 20 to 35% and accelerated the development of cluster roots, which exhibit important functions in chemical mobilization of sparingly soluble soil P sources. Accordingly, cluster root formation was stimulated in plants without P application by 140 and 60% for ambient and elevated CO(2) treatments, respectively. Intense accumulation of citrate and increased activities of acid and alkaline phosphatases, but also of chitinase, in the rhizosphere were mainly confined to later stages of cluster root development in -P treatments. Regardless of atmospheric CO(2) concentrations, there was no significant effect on accumulation of citrate or on selected enzyme activities of C, N, and P cycles in the rhizosphere of individual root clusters. Discriminant analysis of selected enzyme activities revealed that mainly phosphatase and chitinase contributed to the experimental variance (81.3%) of the data. Phosphatase and chitinase activities in the rhizosphere might be dominated by the secretion from cluster roots rather than by microbial activity. Alterations in rhizosphere bacterial communities analyzed by denaturing gradient gel electrophoresis (DGGE) were related with the intense changes in root secretory activity observed during cluster root development but not with elevated CO(2) concentrations.     

NUTRIENT CONCENTRATIONS IN WASTEWATER TREATMENT PLANT EFFLUENTS,SOUTH PLATTE RWER BASIN1

ABSTRACT: Accurate data about nutrient concentrations in wastewater treatment plant effluents are needed for river basin water-quality studies. As part of the U.S. Geological Survey's National Water-Quality Assessment Program in the South Platte River Basin, nutrient data were requested from 31 wastewater-treatment plants located in the basin. This article describes the types of nutrient data available from the plants, examines the variability of effluent nutrient concentrations, and discusses methods for estimation of nutrient concentrations where data are lacking. Ammonia was monitored at 88 percent of the plants, nitrite plus nitrate was monitored at 40 percent of the plants, and organic nitrogen and phosphorus were monitored at less than 25 percent of the plants. Median total nitrogen concentrations and median total phosphorus concentrations were small compared to typical literature estimates for wastewater-treatment plants with secondary treatment. Nutrient concentrations in effluent from wastewater-treatment plants varied widely between and within plants. For example, ammonia concentrations varied as much as 5 mg/L during a day, as much as 10 mg/L from day to day, and as much as 30 mg/L from summer to winter within a plant. In the South Platte River Basin, estimates of median annual ammonia and nitrite plus nitrate concentrations can be improved based on plant processes; and nitrite plus nitrate and organic nitrogen concentrations can be estimated based on ammonia concentrations. However, to avoid large estimation errors, more complete nutrient data from wastewater-treatment plants are needed for integration into river basin water quality studies. The paucity of data hinders attempts to evaluate the relative importance of point source and nonpoint source nutrient loadings to rivers.     

Emissions of ammonia, methane, carbon dioxide, and nitrous oxide from dairy cattle housing and manure management systems

Concentrated animal feeding operations emit trace gases such as ammonia (NH?), methane (CH?), carbon dioxide (CO?), and nitrous oxide (N?O). The implementation of air quality regulations in livestock-producing states increases the need for accurate on-farm determination of emission rates. The objective of this study was to determine the emission rates of NH?, CH?, CO?, and N?O from three source areas (open lots, wastewater pond, compost) on a commercial dairy located in southern Idaho. Gas concentrations and wind statistics were measured each month and used with an inverse dispersion model to calculate emission rates. Average emissions per cow per day from the open lots were 0.13 kg NH?, 0.49 kg CH?, 28.1 kg CO?, and 0.01 kg N?O. Average emissions from the wastewater pond (g m(-2) d(-1)) were 2.0 g NH?, 103 g CH?, 637 g CO?, and 0.49 g N?O. Average emissions from the compost facility (g m(-2) d(-1)) were 1.6 g NH?, 13.5 g CH?, 516 g CO?, and 0.90 g N?O. The combined emissions of NH?, CH?, CO?, and N?O from the lots, wastewater pond and compost averaged 0.15, 1.4, 30.0, and 0.02 kg cow(-1) d(-1), respectively. The open lot areas generated the greatest emissions of NH?, CO?, and N?O, contributing 78, 80, and 57%, respectively, to total farm emissions. Methane emissions were greatest from the lots in the spring (74% of total), after which the wastewater pond became the largest source of emissions (55% of total) for the remainder of the year. Data from this study can be used to develop trace gas emissions factors from open-lot dairies in southern Idaho and potentially other open-lot production systems in similar climatic regions.     

Influence of nutrient levels on uptake and effects of mercury, cadmium, and lead in water spinach

In Southeast Asia the aquatic macrophyte water spinach (Ipomoea aquatica Forsk.) is a popular vegetable that is cultivated in freshwater courses. These often serve as recipients for domestic and other sorts of wastewater that often contain a variety of pollutants, such as heavy metals. In addition, fertilizers are frequently used where water spinach is cultivated commercially for the food market. To estimate the importance of ambient nutrient concentrations for accumulation of mercury (Hg), cadmium (Cd), and lead (Pb) in water spinach, plants were exposed to nutrient solutions of different strength and with varying metal concentrations. Metal-induced toxic effects, which might possibly affect the yield of the plants, were also studied. The lower the nutrient strength in the medium was, the higher the metal concentrations that accumulated in the different plant parts and the lower the metal concentration in the medium at which metal-induced toxic effects occurred. Accordingly, internal metal concentrations in the plants were correlated to toxic effects. Plants exposed to metals retained a major proportion of the metals in the roots, which had a higher tolerance than shoots for high internal metal concentrations.     

Persistence of the fluoroquinolone antibiotic difloxacin in soil and lacking effects on nitrogen turnover

The environmental risks caused by the use of fluoroquinolone antibiotics in human therapeutics and animal husbandry are associated with their persistence and (bio)accessibility in soil. To assess these aspects, we administered difloxacin to pigs and applied the contaminated manure to soil. We then evaluated the dissipation and sequestration of difloxacin in soil in the absence and presence of plants within a laboratory trial, a mesocosm trial, and a field trial. A sequential extraction yielded antibiotic fractions of differing binding strength. We also assessed the antibiotic's effects on nitrogen turnover in soil (potential nitrification and denitrification). Difloxacin was hardly (bio)accessible and was very persistent under all conditions studied (dissipation half-life in bulk soil, >217 d), rapidly forming nonextractable residues. Although varying environmental conditions did not affect persistence, dissipation was accelerated in soil surrounding plant roots. Effects on nitrogen turnover were limited due to the compound's strong binding and small (bio)accessibility despite its persistence.     

Decontamination of water polluted by heavy metals with Taro (Colocasia esculenta) cultured in a hydroponic NFT system

The toxicity and bioaccumulation of two heavy metals—lead (Pb) and cadmium (Cd)—in a semi-aquatic plant, Colocasia esculenta (L. Schott), from a synthetic heavy metal solution were studied. Young plants of equal size were grown hydroponically in shallow raceways containing Hoagland medium amended with 20, 40, and 60 mg l^?1 of Pb and 2, 4, and 6 mg l^?1 of Cd. The medium containing heavy metals was allowed to flow through the raceways with a change in influent heavy metal solution on every 5th day. The experiment was continued for 20 days. A set of control raceways—one comprised of nutrient medium with heavy metal supplements, devoid of plants, and another with the plants and nutrient medium having no metal supplement—was also simultaneously run. Chlorosis in the leaves was the prominent toxicity symptom observed due to Pb and Cd on the test plants. A significant decrease in the relative growth, biomass productivity, and total chlorophyll content were noticed in the plants with an increase in concentration of metal supplement in the solution and exposure time. Both metals accumulated to higher concentrations in the roots than in shoots, suggesting that the metals were bound to the root cells and their translocation to the leaves was limited. The results of the 20-day-long experiments indicate that from a phytoremediation perspective, C. esculenta is a promising plant species for remediation of wastewater polluted with lower concentrations of Pb and Cd.