Metal(loid) oxides and metal sulfides nanomaterials reduced heavy metals uptake in soil cultivated cucumber plants

Advancement of metal oxide nanomaterials on agri-food fronts

The application of metal oxide nanomaterials (MOx NMs) in the agrifood industry offers innovative solutions that can facilitate a paradigm shift in a sector that is currently facing challenges in meeting the growing requirements for food production, while safeguarding the environment from the impacts of current agriculture practices. This review comprehensively illustrates recent advancements and applications of MOx for sustainable practices in the food and agricultural industries and environmental preservation. Relevant published data point out that MOx NMs can be tailored for specific properties, enabling advanced design concepts with improved features for various applications in the agrifood industry. Applications include nano-agrochemical formulation, control of food quality through nanosensors, and smart food packaging. Furthermore, recent research suggests MOx's vital role in addressing environmental challenges by removing toxic elements from contaminated soil and water. This mitigates the environmental effects of widespread agrichemical use and creates a more favorable environment for plant growth. The review also discusses potential barriers, particularly regarding MOx toxicity and risk evaluation. Fundamental concerns about possible adverse effects on human health and the environment must be addressed to establish an appropriate regulatory framework for nano metal oxide-based food and agricultural products.

Effects of remediation agents on rice and soil in toxic metal(loid)s contaminated paddy fields: A global meta-analysis

Toxic metal(loid)s contamination of paddy soil is a nonnegligible issue and threatens food safety considering that it is transmitted via the soil-plant system. Applying remediation agents could effectively inhibit the soil available toxic metal(loid)s and reduce their accumulation in rice. To comprehensively quantify how remediation agents impact the accumulation of Cd/Pb/As in rice, rice growth and yield, the accumulation of available Cd/Pb/As in paddy soil, and soil characteristics, 50 peer-reviewed publications were selected for meta-analysis. Overall, the application of remediation agents exhibited significant positive effects on rice plant length (ES = 0.05, CI = 0.01-0.08), yield (ES = 0.20, CI = 0.13-0.27), peroxidase (ES = 0.56, CI = 0.18-0.31), photosynthetic rate (ES = 0.47, CI = 0.34-0.61), and respiration rate (ES = 0.68, CI = 0.47-0.88). Among the different types of remediation agents, biochar was the most effective in controlling the accumulation of Cd/Pb/As in all portions of rice, and was also superior in inhibiting the accumulation of Pb in rice grains (ES = -0.59, 95 % CI = -1.04-0.13). This study offers an essential contribution for the remediation strategies of toxic metal(loid)s contaminated paddy fields.

Analyzing heavy metal contamination for one of the high-rate consumption fruits in Iran: A probabilistic health risk assessment

Good health and well-being is one of the sustainable development goals (SDGs) that can be achieved through fruit consumption. This study measured cucumber (Cucumis sativus L.) heavy metal concentrations. Inductively coupled plasma-mass spectrometry (ICP-OES) was used to analyze the samples for heavy metal content. The uncertainty and sensitivity analyses of carcinogenic and non-carcinogenic heavy metal intake via cucumber (Cucumis sativus L.) consumption were assessed by Monte Carlo simulation. The mean ± SD levels of Cu, Pb, Zn, Cd, and As were determined to be 157.87 ± 128.54, 33.81 ± 6.27, 288.46 ± 114.59, 35.22 ± 18.67, and 33.6 ± 18.1 μg/kg, respectively. The 95th percentile of HI related to heavy metal intake via cucumber (Cucumis sativus L.) among children and adults were 2.64 and 1.75, respectively. Also, the 95th percentile of ELCR related to heavy metal were 8.26E-4 and 4.14E-3 among children and adults, respectively. The 95th percentile of LTCR of As among adults and As, Cd, and Pb among children were in the WHO target range (1E-04 to 1E-06) so reducing the concentration of them can help to reduce overall LTCR. When HQ and LTCR are below the cut limits, reducing heavy metals in high-consumption meals is a good way to lower them. In general, due to the wide consumption of various fruits, such as cucumber (Cucumis sativus L.), the concentration of environmental pollutants in their edible tissues should be monitored regularly, and the concentration of pollutants in these tissues should be minimized by proper planning.

Mitigation of the mobilization and accumulation of toxic metal(loid)s in ryegrass using sodium sulfide

Remediation of soils contaminated with toxic metal(loid)s (TMs) and mitigation of the associated ecological and human health risks are of great concern. Sodium sulfide (Na2S) can be used as an amendment for the immobilization of TMs in contaminated soils; however, the effects of Na2S on the leachability, bioavailability, and uptake of TMs in highly-contaminated soils under field conditions have not been investigated yet. This is the first field-scale research study investigating the effect of Na2S application on soils with Hg, Pb and Cu contents 70-to-7000-fold higher than background values and also polluted with As, Cd, Ni, and Zn. An ex situ remediation project including soil replacement, immobilization with Na2S, and safe landfilling was conducted at Daiziying and Anle (China) with soils contaminated with As, Cd, Cu, Hg, Ni, Pb and Zn. Notably, Na2S application significantly lowered the sulfuric-nitric acid leachable TMs below the limits defined by Chinese regulations. There was also a significant reduction in the DTPA-extractable TMs in the two studied sites up to 85.9 % for Hg, 71.4 % for Cu, 71.9 % for Pb, 48.1 % for Cd, 37.1 % for Zn, 34.3 % for Ni, and 15.7 % for As compared to the untreated controls. Moreover, Na2S treatment decreased the shoot TM contents in the last harvest to levels lower than the TM regulation limits concerning fodder crops, and decreased the TM root-to-shoot translocation, compared to the untreated control sites. We conclude that Na2S has great potential to remediate soils heavily tainted with TMs and mitigate the associated ecological and human health risks.

Effects of soil amendments on Cd and As mobility in the soil-rice system and their distribution in the grain

The accumulation, mobilization, and distribution of toxic metal(loid)s in rice are key factors that affect food security and determine bio-utilization patterns. In this study, five soil amendments with different components were used in paddy fields to study the key factors: organic amendments: (1) polyaspartic acid (OA1) and (2) organic fertilizer (OA2); inorganic amendments: (3) kaolinite (IA1) and (4) magnesium slag (IA2); and organic-inorganic composite amendments: (5) modified biochar/quicklime (OIA). Although the Cd and As exhibited opposite chemical dissolution behaviors, IA1/OIA, can simultaneously reduce their accumulation and transfer coefficients in rice tissues, while other amendments only work for one of them. The in situ distribution in grains showed that IA1/OIA changed the original Cd distribution in the lemma and palea, whereas all amendments reduced Cd accumulation in the germ. In contrast, OA1/IA2 amendments led to more As accumulation in the rice husks and bran than in the endosperm center, and the germ had higher As signals. Because of their similar transport pathways and interactions, the concentrations of Cd and As in the grains were correlated with a variety of mineral elements (Fe, Mo, Zn, etc.). Changes in the Cd/As concentration and distribution in rice were achieved through the improvement of soil properties and plant growth behavior through amendments. The application of OIA resulted in the highest immobilization indices, at 82.17 % and 35.34 % for Cd and As, respectively. The Cd/As concentrations in the rice grains were highly positively correlated with extractable-Cd/As in the soil (Cd: R2 = 0.95, As: R2 = 0.93). These findings reveal the migration and distribution mechanisms of Cd and As in the soil-rice system, and thus provide fundamental information for minimizing food safety risk.

Potential functions of engineered nanomaterials in cadmium remediation in soil-plant system: A review

Soil cadmium (Cd) contamination is a global environmental issue facing agriculture. Under certain conditions, the stable Cd that bound to soil particles tend to be remobilized and absorbed into plants, which is seriously toxic to plant growth and threat food safety. Engineering nanomaterials (ENMs) has attracted increasing attentions in the remediation of Cd pollution in soil-plant system due to their excellent properties with nano-scale size. Herein, this article firstly systematically summarized Cd transformation in soil, transport in soil-plant system, and the toxic effects in plants, following which the functions of ENMs in these processes to remediate Cd pollution are comprehensively reviewed, including immobilization of Cd in soil, inhibition in Cd uptake, transport, and accumulation, as well as physiological detoxication to Cd stress. Finally, some issues to be further studied were raised to promote nano-remediation technology in the environment. This review provides a significant reference for the practical application of ENMs in remediation of Cd pollution in soil, and contributes to sustainable development of agriculture.

Ti3C2Tx MXene nanosheets enhance the tolerance of Torreya grandis to Pb stress

As a 2D nanomaterial, MXene (Ti₃C₂T_x) has shown enormous potential for use in fields such as biomedical and environmental pollution. However, the utilization of MXene materials in plants has received little attention thus far. The efficient use of MXene materials in agriculture and forestry is first highlighted in this study. Phenotypic and physiological analyses indicated that MXene application significantly enhanced the tolerance of Torreya grandis to Pb stress by reducing Pb accumulation. Furthermore, we illustrated two independent mechanisms of MXene material in reducing Pb accumulation in T. grandis: 1) MXene converted the available form of Pb into stable forms via its strong Pb adsorption ability, resulting in a decrease of the available form of Pb in soils, and 2) MXene application obviously increased the cell wall pectin content to restrict more Pb in the cell wall by regulating the expression of pectin synthesis/metabolism-related genes (TgPLL2, TgPLL11, TgPG5, TgPG30, TgGAUT3 and TgGAUT12) in T. grandis roots. Overall, this finding provides insight into the application of MXene material in modern agriculture and forestry, which will facilitate the rapid development of nanotechnology in sustainable agriculture and forestry.

The immobilization, plant uptake and translocation of cadmium in a soil-pakchoi (Brassica chinensis L.) system amended with various sugarcane bagasse-based materials

Many organic materials have been used to decrease heavy-metal bioavailability in soil via in-situ remediation due to its high efficiency and easy operation; meanwhile, cheap materials have also been pursued to decrease the cost of remediation. Agricultural wastes exhibit their potential in remediation materials due to their low cost; however, raw agricultural wastes have a low ability to immobilize heavy metals in soil. Attempts have been made to modify agricultural wastes to improve the efficiency of heavy-metal passivation. In this study, novel agricultural waste-based materials, raw sugarcane bagasse (SB), citric acid modified (SSB) and citric-acid/Fe₃O₄ modified (MSB) sugarcane bagasse at 0.5% and 1% addition rates, were compared for their effectiveness in soil Cd passivation and Cd accumulations in pakchoi plants in a 30-day pot experiment. The addition of SB did not decrease soil bioavailable Cd effectively and slightly decreased Cd accumulation in plant roots and leaves. In comparison, SSB and MSB exhibited a great potential to decrease the transformation, translocation and accumulation of Cd with the decrease being greater at 1% than 0.5% rate in the soil-pakchoi system. For example, the addition of SSB and MSB at 0.5% decreased the concentration of Cd in leaves by 10%, and 16%, and at 1% decreased the concentration by 25% and 30%, respectively. High pH and abundant functional groups of three amendments played important roles in Cd immobilization. The enhanced microbial activities might also contribute to Cd passivation. However, plant growth was decreased in the amended treatments except SSB at 0.5% rate. The results suggest that citric-acid-modified sugarcane bagasse at addition rate of 0.5% has a potential to immobilize Cd in soil and decrease Cd accumulation in edible part of pakchoi effectively without decreasing vegetable growth.

Assessing the influence of sewage sludge and derived-biochar in immobilization and transformation of heavy metals in polluted soil: Impact on intracellular free radical formation in maize

As one of the most common ways to get rid of municipal waste, landfill leachate, waste with complicated compositions and high levels of contaminants, has become a significant threat to the world's environment. Here, the impact of sewage sludge (SS) and derived-biochar (SSB) amendments on the immobilization and potential mobility of heavy metals in a contaminated soil-plant system was investigated. The sequential fractionation findings showed that using SS-2%, SSB-2%, and SSBC-1% reduced the potential mobility of heavy metals while increasing the residual fraction in polluted soils. The translocation and bioconcentration factors showed that heavy metals were slightly transferred into shoots from roots and lowered accumulation in roots from contaminated soils. Fourier transform infrared (FTIR) and X-ray photoelectron spectrum (XPS) comprehensive characterization results indicated the significant role of applied amendments for heavy metals transformation from the exchangeable-soluble fractions to the least available form by lowering their mobility to confirm the adsorption-based complexes, which results in the surface adsorption of heavy metals with functional groups. The electron paramagnetic resonance (EPR) results indicated the dominance of reactive oxygen species (ROS) in the intracellular formation of hydroxyl radicals (•OH) in maize plant roots and shoots. ROS (•OH) generation plays a critical influence in the interaction between the physiological processes of plants and heavy metals. Moreover, all the amendments increased maize growth and biomass production. Our study suggests that alone and combined application of SS and SSB have great potential to remediate heavy metals contaminated soil for environmental sustainability.

Efficient and selective removal of Pb2+ from aqueous solution by using an O- functionalized metal-organic framework

Lead (Pb) is one of the most widespread and highly toxic heavy metals in the environment. The design and synthesis of adsorbent materials for the selective and efficient removal of Pb²⁺ from aqueous solution has received much attention. Herein, the ligand 4,4'-azoxydibenzoic acid with the O^- group was elaborately selected to construct a novel Pr-based MOF for Pb²⁺ removal. The as-prepared MOF adsorbents with high stability exhibited ultra-high selectivity for Pb²⁺, even in the presence of various highly concentrated competitive ions (with the ratios from 1 : 5 to 1 : 50). Also, a high uptake capacity (560.26 mg g^-1) can be achieved for the MOF material, due to the availability of sufficient adsorption sites. The strong electrostatic attraction and coordination interaction between the numerous active O^- sites on MOF adsorbents and Pb²⁺ can account for the good adsorption performance for Pb²⁺, which was systematically verified by zeta potential, FT-IR and XPS studies.

Silicon nanoparticles decrease arsenic translocation and mitigate phytotoxicity in tomato plants

In this study, we simulate the irrigation of tomato plants with arsenic (As)-contaminated water (from 0 to 3.2 mg L^-1) and investigate the effect of the application of silicon nanoparticle (Si NPs) in the form of silicon dioxide (0, 250, and 1000 mg L^-1) on As uptake and stress. Arsenic concentrations were determined in substrate and plant tissue at three different stratums. Phytotoxicity, As accumulation and translocation, photosynthetic pigments, and antioxidant activity of enzymatic and non-enzymatic compounds were also determined. Our results show that irrigation of tomato plants with As-contaminated water caused As substrate enrichment and As bioaccumulation (roots > leaves > steam), showing that the higher the concentration in irrigation water, the farther As translocated through the different tomato stratums. Additionally, phytotoxicity was observed at low concentrations of As, while tomato yield increased at high concentrations of As. We found that application of Si NPs decreased As translocation, tomato yield, and root biomass. Increased production of photosynthetic pigments and improved enzymatic activity (CAT and APX) suggested tomato plant adaptation at high As concentrations in the presence of Si NPs. Our results reveal likely impacts of As and nanoparticles on tomato production in places where As in groundwater is common and might represent a risk.

Novel agricultural waste-based materials decrease the uptake and accumulation of cadmium by rice (Oryza sativa L.) in contaminated paddy soils

Heavy metal pollution in paddy fields has caused widespread concerns due to the threat to food safety. The present study used low-cost sugarcane bagasse (SB) and two sugarcane bagasse materials modified with citric-acid (SSB) and citric-acid/Fe₃O₄ (MSB) to investigate their effects on the bioavailability of Cd in soil and Cd accumulations in rice in a pot experiment. The three organic amendments significantly decreased the Cd accumulation in plants by limiting its mobilization in soil. The MSB and SSB but not SB increased the soil pH and immobilized the Cd in soil significantly during the 120-day experiment. The amendments decreased Cd bioavailability through transforming to the stable fraction throughout the whole growth stage. The functional groups in the amendments (-OH, -COOH, C-O, -COO^- and Fe-O) and precipitates [Cd(NO₂)₂K(NO₂)₂, Cd(OH)₂ and Cd₇₅Zn₂₅Fe₂O₄] played active roles in Cd immobilization. Moreover, the three organic materials increased the content of Fe-Mn plaque on rice roots, which prevented its transport from soil to rice roots further. We also found that Fe competed with Cd for transporters and reduced potential Cd uptake and translocation in rice tissues. The addition of MSB and SB but not SSB inhibited the rice growth compared to the unamended control, indicating the potential of SSB in situ remediation. These results provide valuable information to use organic amendments for Cd passivation in soil and food safety.

Low levels of TiO2-nanoparticles interact antagonistically with Al and Pb alleviating their toxicity

The contamination and bioavailability of deleterious metals in arable soils significantly limits crop development and yield. Aiming at mitigating Pb- and Al-induced phytotoxicity, this work explores the use of P25 titanium dioxide nanoparticles (nTiO₂) in soil amendments. For that, Lactuca sativa L. plants were germinated and grown in the presence of 10 ppm Pb or 50 ppm Al, combined or not with 5 ppm nTiO₂. Growth parameters, as well as endpoints of the redox state [cell relative membrane permeability (RMP), thiobarbituric acid reactive substances content, total phenolic content and photosynthesis (sugars and pigments levels, chlorophyll a fluorescence and gas exchange), were evaluated. Concerning Al, nTiO₂ treatment alleviated the impairments induced in germination rate, seedling length, water content, RMP, stomatal conductance (g_s), intercellular CO₂ (C_i), and net CO₂ assimilation rate (P_N). It increased anthocyanins contents and effective efficiency of photosystem II (Φ_PSII). In Pb-exposed plants, nTiO₂ amendment mitigated the effects in RMP, P_N, g_s, and C_i. It also increased the pigment contents and the transpiration rate (E) comparatively to the control without nTiO₂. These results clearly highlight the high potential of low doses of nTiO₂ in alleviating metal phytotoxicity, particularly the one of Pb. Additionally, further research should explore the use of these nanoparticles in agricultural soil amendments.

Investigation of plant contamination to Ni, Pb, Zn, and Cd and its relationship with spectral reflections

This study aims to investigate the toxicity of the plant to heavy elements (HMs). For this purpose, the estimated daily intake (EDI) parameters of potentially toxic elements (PTE) per kilogram of body weight, target hazard quotient (THQ) for non-carcinogenic disorders, total hazard index (HI), and bioconcentration factor (BCF) are determined in the plant at different stages of growth. In this study, the reaction of the plant to different electromagnetic waves at different stages of growth (DSG) is also investigated, and the relationship between the THQ values and electromagnetic waves is prepared. The results show that Pb has the highest EDI value (5.97), Pb (74.67) and Cd (9.75) have the highest THQ values, and Cd has the highest BCF value (30.44). Also, the results show that HI values are higher than the threshold in the growth (69.98), flowering (71.38), and fruiting (68.06) stages. Results of BCF indicate Pb, and Cd has absorption rate in Capsicum towards. Contaminated Capsicum plants submitted to electromagnetic waves showed a significant relationship between Pb and the b490, and b560 spectra, Cd and Ni the b450 spectrum, and Zn the b460 spectrum. This finding highlights the salience of employing electromagnetic waves in assessing contamination in plants. Put differently, THQ can be estimated using electromagnetic waves without any need for laboratory studies.

Effect of different vegetation on copper accumulation of copper-mine abandoned land in tongling, China

Mining activity and abandoned mine land are one of the major sources of heavy metal pollution. Thus, ecological rehabilitation of abandoned mine lands is crucial to control heavy metal pollution. This research aims to explore the influencing factors and effects of different vegetation on copper (Cu) accumulation and soil amelioration. In this study, the abandoned land of Tongguanshan Cu mine in Tongling city, Anhui province, China, was chosen as the test area, and nine sampling points were established. Samples of soil and plants were collected from each plot, and the impacts of Cu pollution on soil enzymes and other features were analyzed, as well as the correlation between Cu accumulation of different plants and soil properties. The results showed that Cu content of soil in the Tongguanshan area varied greatly with the depth of the soil profile. Moreover, Cu in the soil can inhibit soil enzyme activities; and the correlation coefficients of total soil Cu with urease and catalase were -0.83 and -0.73, respectively. Clearly, the accumulation of Cu in plants was positively correlated with Cu content in soil. It was found that Pueraria lobata had the best remediation effect on soil Cu pollution in a short period of time. Hence the preliminary tests clearly indicate that phytoremediation in abandoned mine lands can not only reduce heavy metal pollution, but also enhance soil nutrition and enzyme activity, helping to ameliorate degraded land and promote regional socioeconomic sustainable development.

Transformation of copper oxide and copper oxide nanoparticles in the soil and their accumulation by Hordeum sativum

In recent years, the study of the influence of nanoparticles (NPs) on the environment has attracted much interest as nanotechnology is becoming the key technology of the future generation. The comparative studies on the effects of macro- and nanosized copper oxide (CuO) on plants rarely cover the state and behaviour of CuO in the soil-plant system. This work considers the transformation of CuO in Haplic Chernozem depending on the degree of dispersion and its toxic effects on spring barley (Hordeum sativum) growth. To investigate the transformation of the studied particles of metal oxide in the soil and plant, both chemical method of analysis and synchrotron radiation X-ray powder diffraction, X-ray absorption near-edge structure spectroscopy (XANES) and X-ray absorption fine-structure spectroscopy (EXAFS) were used. It was shown that CuO NPs underwent a stronger transformation due to the high reactivity of smaller particles. The Cu mobility was observed to increase within the soil profile as confirmed by the model pollution experiment. This is mainly due to the formation of complex forms of metal with organic matter. A dose of 300 mg/kg of macro- and nanosized CuO did not significantly affect the development and productivity of spring barley. The effect of high doses of macro- and nanosized CuO (2000 and 10,000 mg/kg) had a negative impact on the growth of spring barley. The application of nanosized CuO had a greater toxic effect than the macrosized CuO on the plants. The XANES and EXAFS data revealed that CuO NPs accumulated in the soil and plants. The linear combination fit shown that Cu atoms, incorporated into the plants, have environment typical of CuO. This indicates a high environmental risk when soil is contaminated with CuO NPs compared with its arrival as CuO.

Knowledge domain and emerging trends in nanoparticles and plants interaction research: A scientometric analysis

The potential releases of nanoparticles (NPs) into soil medium have drawn considerable attention due to the increasing production and application of NPs worldwide. Understanding the interactions between NPs and plants is particularly important to assess the risks of NPs in the soil ecosystem. Although important knowledge has been gained about the NPs-plants interactions, current results of numerous published articles are still scattered. Therefore, this paper reviews the scientific progress in the NPs-plants interactions via a scientometric analysis to identify the main gaps and to provide future perspectives. Scientific documents on the interaction of nanoparticles and plant research during the period January 2000-July 2020 have been collected from Web of Science core collection and analyzed using CiteSpace. Overall, 9 scientometric indicators, i.e. literature quantity and growth trend, contributing countries, authors, institutions, keywords, cited journals, cited authors, and cited articles, are employed to understand the results retrieved from the 961 documents collected. The number of studies on nano-plant interaction research has been growing at an average annual rate of 56%. 71 countries and around 3380 authors have contributed to this field. Among the cited journals, Environmental Science and Technology stands out as the most-cited journal followed by Science of the Total Environment and Environmental Pollution, respectively. Moreover, the keyword citation burst, an indicator of the most active area of research or emerging trend, indicates that the beneficial side of nanoparticles and the trophic transfer require further exploration. This paper will be beneficial for fully understanding the salient research themes and the research trends of nano-plant interaction in future.

Application of Nanomaterials in Regulating the Fate of Adipose-derived Stem Cells

Adipose-derived stem cells are adult stem cells which are easy to obtain and multi-potent. Stem-cell therapy has become a promising new treatment for many diseases, and plays an increasingly important role in the field of tissue repair, regeneration and reconstruction. The physicochemical properties of the extracellular microenvironment contribute to the regulation of the fate of stem cells. Nanomaterials have stable particle size, large specific surface area and good biocompatibility, which has led them being recognized as having broad application prospects in the field of biomedicine. In this paper, we review recent developments of nanomaterials in adipose-derived stem cell research. Taken together, the current literature indicates that nanomaterials can regulate the proliferation and differentiation of adipose-derived stem cells. However, the properties and regulatory effects of nanomaterials can vary widely depending on their composition. This review aims to provide a comprehensive guide for future stem-cell research on the use of nanomaterials.

Pteris vittata coupled with phosphate rock effectively reduced As and Cd uptake by water spinach from contaminated soil

Arsenic (As) and cadmium (Cd) are ubiquitous in the environment and they are both toxic to humans. When present in soils, they can enter food chain, thereby threatening human health. Water spinach (Ipomoea aquatica) is an important leafy vegetable, which is widely consumed in Asian countries. However, it is efficient in taking up As and Cd from soils and accumulating them in the edible parts. Therefore, it is of significance to reduce its As and Cd content, especially in contaminated soil. In this study, pot experiments were conducted to investigate the ability of As-hyperaccumulator Pteris vittata in reducing As and Cd uptake by water spinach under different phosphorus treatments. P. vittata was grown for 60 d in a contaminated-soil amended with P fertilizer (+P) or phosphate rock (+PR), followed by water spinach cultivation for another 30 d. Plant biomass, As and Cd contents in plants and soils, and soil pH were analyzed. We found that, P. vittata coupled with PR decreased the As concentration in water spinach shoots by 42%, probably due to As uptake by P. vittata. Moreover, P. vittata decreased the Cd accumulation in water spinach by 24-44%, probably due to pH increase of 0.47-0.61 after P. vittata cultivation. Taking together, the results showed that P. vittata coupled with PR decreased the As and Cd content in water spinach, which is of significance for improving food safety and protecting human health.