ID: 15698640
Title: The arbuscular mycorrhizal fungus Glomus mosseae induces growth and metal accumulation changes in Cannabis sativa L.
Abstract: The effect of arbuscular mycorrhiza on heavy metal uptake and translocation was investigated in Cannabis sativa. Hemp was grown in the presence and absence of 100 microg g-1 Cd and Ni and 300 microg g-1 Cr(VI), and inoculated or not with the arbuscular mycorrhizal fungus Glomus mosseae. In our experimental condition, hemp growth was reduced in inoculated plants and the reduction was related to the degree of mycorrhization. The percentage of mycorrhizal colonisation was 42% and 9% in plants grown in non-contaminated and contaminated soil, suggesting a significant negative effect of high metal concentrations on plant infection by G. mosseae. Soil pH, metal bioavailability and plant metal uptake were not influenced by mycorrhization. The organ metal concentrations were not statistically different between inoculated and non-inoculated plants, apart from Ni which concentration was significantly higher in stem and leaf of inoculated plants grown in contaminated soil. The distribution of absorbed metals inside plant was related to the soil heavy metal concentrations: in plant grown in non-contaminated soil the greater part of absorbed Cr and Ni was found in shoots and no significant difference was determined between inoculated and non-inoculated plants. On the contrary, plants grown in artificially contaminated soil accumulated most metal in root organ. In this soil, mycorrhization significantly enhanced the translocation of all the three metals from root to shoot. The possibility to increase metal accumulation in shoot is very interesting for phytoextraction purpose, since most high producing biomass plants, such as non-mycorrhized hemp, retain most heavy metals in roots, limiting their application.

ID: 19393309
Title: Cadmium tolerance and accumulation in eight potential energy crops.
Abstract: The production of energy crops that can be used for biodiesel production is a sustainable approach for the removal of metal pollutants by phytoremediation. This study investigated the cadmium (Cd) accumulation and tolerance of eight potential energy crops. After growth for 28 days in substrates containing 0, 50, 100 or 200 mg Cd x kg(-1), seedlings were evaluated for growth parameters, chlorophyll content, chlorophyll fluorescence parameters and Cd accumulation. All eight crops were moderately tolerant to Cd toxicity, with four [i.e., hemp (Cannabis sativa), flax (Linum usitatissimum), castor (Ricinus communis) and peanut (Arachis hypogaea)] being more tolerant than the others. Three of these crops (hemp, flax and peanut) had higher Cd accumulation capacities. The roots of peanut and hemp had high bioconcentration factors (BCF>1000), while flax shoots accumulated a higher concentration of Cd (>100 mg/kg). These results demonstrate that it is possible to grow energy crops on Cd-contaminated soil. Hemp, flax and peanut are excellent candidates for phytoremediation.

ID: 21938417
Title: Cadmium tolerance and bioaccumulation of 18 hemp accessions.
Abstract: Hemp (Cannabis sativa L.) is a fast-growing and high biomass producing plant species, which has been traditionally grown as multiple-use crop and recently considered as an energy crop. In order to screen accessions that can be cultivated in cadmium (Cd)-contaminated soils for biodiesel production, the ability of Cd tolerance and bioaccumulation of 18 hemp cultivars or ecotypes were evaluated in pot experiment under 25 mg Cd kg(-1) (dry weight, DW) soil condition, in terms of plant growth, pigment contents, chlorophyll fluorescence, and Cd accumulation at 45 days after seedling emergence. Results showed that seedlings of all cultivars, except USO-31, Shenyang and Shengmu, could grow quite well under 25 mg Cd kg(-1) (DW) soil condition. Among them, Yunma 1, Yunma 2, Yunma 3, Yunma 4, Qujing, Longxi, Lu'an, Xingtai, and Shuyang showed great biomass (>0.5 g plant(-1)), high tolerance factors (68.6-92.3%), and little reduction of pigment content and chlorophyll fluorescence under 25 mg Cd kg(-1) (DW) soil stress, indicating these cultivars had a strong tolerance to Cd stress and could be cultivated in Cd-contaminated soils. Cultivars Longxi, Lu'an, Xingtai, Yunma 2, Yunma 3, Yunma 4, and Qujing exhibited higher Cd concentrations and total Cd in shoots. These cultivars, therefore, are good candidates for the implementation of the new strategy of cultivating biodiesel crops for phytoremediation of Cd-contaminated soils.

ID: 25174425
Title: Effective Phytoextraction of Cadmium (Cd) with Increasing Concentration of Total Phenolics and Free Proline in Cannabis sativa (L) Plant Under Various Treatments of Fertilizers, Plant Growth Regulators and Sodium Salt.
Abstract: The comparative effect of fertilizers (NPK), plant growth regulators (GA3, IAA, Zeatin) and sodium chloride (NaCl) on Cd phytoaccumulation, proline and phenolics production in Cannabis sativa was evaluated. Proline and phenolices were correlated with Cd contents in plant. Cd significantly reduced the plant growth. Fertilizers application (in combination) most significantly increased the growth (19 cm root and 47 cm shoot) on Cd contaminated soil. All treatments increased the Cd contents in plant tissues. This increase was highly significant in fertilizers treated plants (1101, 121 and 544 ppm in roots, stem and leaves respectively). Significantly positive correlation was found between Cd concentration and dry biomass of root (R2=0.7511) and leaves (R2=0.5524). All treatments significantly increased the proline and total phenolics and maximum was recorded in NaCl treated plants followed by fertilizers. Proline was higher in roots while phenolics in leaves. The correlation between proline and phenolics was positive in leaf (R2=0.8439) and root (R2=0.5191). Proline and phenolics showed positive correlation with Cd concentration in plant. Conclusively, fertilizers in combination seem to be the better option for Cd phytoextraction. Further investigation is suggested to study the role of phenolics and proline in Cd phytoextraction.

ID: 26366840
Title: Phytoaccumulation of Heavy Metals in Natural Vegetation at the Municipal Wastewater Site in Abbottabad, Pakistan.
Abstract: Heavy metal accumulation in crops and soils from wastewater irrigation poses a significant threat to the human health. A study was carried out to investigate the removal potential of heavy metals (HM) by native plant species, namely Cannabis sativa L., Chenopodium album L., Datura stramonium L., Sonchus asper L., Amaranthus viridus L., Oenothera rosea (LHer), Xanthium stramonium L., Polygonum macalosa L., Nasturtium officinale L. and Conyza canadensis L. growing at the municipal wastewater site in Abbottabad city, Pakistan. The HM concentrations varied among plants depending on the species. Metal concentrations across species varied in the order iron (Fe) > zinc (Zn) > chromium (Cr) > nickel (Ni) > cadmium (Cd). Majority of the species accumulated more HM in roots than shoots. Among species, the concentrations (both in roots and shoots) were in the order C. sativa > C. album > X. stramonium > C. canadensis > A. viridus > N. officinale > P. macalosa > D. stramonium > S. asper > O. rosea. No species was identified as a hyperaccumulator. All species exhibited a translocation factor (TF) less than 1. Species like C. sativa, C. album and X. stramonium gave higher (> 1) biological concentration factor (BCF) and biological accumulation coefficient (BAC) especially for Fe, Cr and Cd than other species. Higher accumulation of heavy metals in these plant species signifies the general application of these species for phytostabilization and phytoextraction of HM from polluted soils.

ID: 31121980
Title: Protein Changes in Response to Lead Stress of Lead-Tolerant and Lead-Sensitive Industrial Hemp Using SWATH Technology.
Abstract: Hemp is a Pb-tolerant and Pb-accumulating plant and the study of its tolerance mechanisms could facilitate the breeding of hemp with enhanced Pb tolerance and accumulation. In the present study, we took advantage of sequential window acquisition of all theoretical mass spectra (SWATH) technology to study the difference in proteomics between the leaves of Pb-tolerant seed-type hemp variety Bamahuoma (BM) and the Pb-sensitive fiber-type hemp variety Yunma 1 (Y1) under Pb stress (3 g/kg soil). A total of 63 and 372 proteins differentially expressed under Pb stress relative to control conditions were identified with liquid chromatography electro spray ionization tandem mass spectrometry in BM and Y1, respectively; with each of these proteins being classified into 14 categories. Hemp adapted to Pb stress by: accelerating adenosine triphosphate (ATP) metabolism; enhancing respiration, light absorption and light energy transfer; promoting assimilation of intercellular nitrogen (N) and carbon (C); eliminating reactive oxygen species; regulating stomatal development and closure; improving exchange of water and CO2 in leaves; promoting intercellular transport; preventing aggregation of unfolded proteins; degrading misfolded proteins; and increasing the transmembrane transport of ATP in chloroplasts. Our results provide an important reference protein and gene information for future molecular studies into the resistance and accumulation of Pb in hemp.

ID: 31545186
Title: Growth stage and molybdenum treatment affect cadmium accumulation, antioxidant defence and chlorophyll contents in Cannabis sativa plant.
Abstract: Cadmium (Cd) uptake and accumulation in plant tissues is affected by physiological stage of a plant and presence of mineral nutrients in soil. We investigate the effect of micronutrient Mo (0.5, 1.0 and 2.0 ppm) on biomass, Cd accumulation, photosynthetic pigments and endogenous phenolics and soluble proline in Cannabis sativa plant grown in 25 and 50 ppm Cd polluted soil. Molybdenum was applied as seed soaking and soil addition treatments. The plants were harvested in two stages i.e. vegetative (6 weeks) and reproductive stages (12 weeks). It was found that seed soaking treatment of 1.0 ppm Mo most significantly increased biomass, Cd accumulation (1.76 ± 0.19 mg Cd/DBM) and phenolics (104.5 ± 4.46 ppm) concentration in the plant tissues. Molybdenum treatments highly increased Cd bio-concentration at reproductive stage as compared to vegetative stage in plants grown in 50 ppm Cd polluted soil. Translocation of Cd from roots into leaves was significantly increased by Mo treatments at reproductive stage as compared to vegetative stage. Strong inter-correlations existed between total phenolics, Cd accumulation, dry biomass and chlorophyll contents of the plant.

ID: 32888151
Title: Bioaccumulation potential of indigenous plants for heavy metal phytoremediation in rural areas of Shaheed Bhagat Singh Nagar, Punjab (India).
Abstract: The present study was planned to explore the bioaccumulation potential of 23 plant species via bioaccumulation factor (BAf), metal accumulation index (MAI), translocation potential (Tf), and comprehensive bioconcentration index (CBCI) for seven heavy metals (cadmium, chromium, cobalt, copper, iron, manganese, and zinc). The studied plants, in the vicinity of ponds at Sahlon: site 1, Chahal Khurd: site 2, and Karnana: site 3 in Shaheed Bhagat Singh Nagar, Punjab (India), were Ageratum conyzoides (L.) L., Amaranthus spinosus L., Amaranthus viridis L., Brassica napus L., Cannabis sativa L., Dalbergia sissoo DC., Duranta repens L., Dysphania ambrosioides (L.) Mosyakin & Clemants, Ficus infectoria Roxb., Ficus palmata Forssk., Ficus religiosa L., Ipomoea carnea Jacq., Medicago polymorpha L., Melia azedarach L., Morus indica L., Malva rotundifolia L., Panicum virgatum L., Parthenium hysterophorus L., Dolichos lablab L., Ricinus communis L., Rumex dentatus L., Senna occidentalis (L.) Link, and Solanum nigrum L. BAf and Tf values showed high inter-site deviations for studied metals. MAI values were found to be more substantial in shoots as compared with that of roots of plants. Maximum CBCI values were observed for M. azedarach (0.626), M. indica (0.572), D. sissoo (0.497), and R. communis (0.474) for site 1; F. infectoria (0.629), R. communis (0.541), D. sissoo (0.483), F. palmata (0.457), and D. repens (0.448) for site 2; D. sissoo (0.681), F. religiosa (0.447), and R. communis (0.429) for site 3. Although, high bioaccumulation of individual metals was observed in herbs like C. sativa, M. polymorpha, and Amaranthus spp., cumulatively, trees were found to be the better bioaccumulators of heavy metals.

ID: 33728605
Title: Silicon reduces cadmium absorption and increases root-to-shoot translocation without impacting growth in young plants of hemp (Cannabis sativa L.) on a short-term basis.
Abstract: Textile hemp (Cannabis sativa L.) is a non-edible multipurpose crop suitable for fiber production and/or phytoremediation on moderately heavy metal-contaminated soils. Experiments were conducted in nutrient solution to assess the short-term impact of silicon (Si), a well-known beneficial element, on plants exposed to 20 μM cadmium (Cd) in nutrient solution. Cd decreased plant growth and affected photosynthesis through non-stomatal effects. Cd translocation factor was higher than 1, confirming the interest of hemp for phytoextraction purposes. Additional Si did not improve plant growth after 1 week of treatment but decreased Cd accumulation in all organs and improved water use efficiency through a decrease in transpiration rate. Si had only marginal impact on Cd distribution among organs. It increased glutathione and phytochelatin synthesis allowing the plants to efficiently cope with oxidative stress through the improvement of Cd sequestration on thiol groups in the roots. Si may thus have a fast impact on the plant behavior before the occurrence of plant growth stimulation.

ID: 34539703
Title: Molecular and Biochemical Insights Into Early Responses of Hemp to Cd and Zn Exposure and the Potential Effect of Si on Stress Response.
Abstract: With the intensification of human activities, plants are more frequently exposed to heavy metals (HM). Zinc (Zn) and cadmium (Cd) are frequently and simultaneously found in contaminated soils, including agronomic soils contaminated by the atmospheric fallout near smelters. The fiber crop Cannabis sativa L. is a suitable alternative to food crops for crop cultivation on these soils. In this study, Cd (20 μM) and Zn (100 μM) were shown to induce comparable growth inhibition in C. sativa. To devise agricultural strategies aimed at improving crop yield, the effect of silicon (Si; 2 mM) on the stress tolerance of plants was considered. Targeted gene expression and proteomic analysis were performed on leaves and roots after 1 week of treatment. Both Cd- and Zn-stimulated genes involved in proline biosynthesis [pyrroline-5-carboxylate reductase (P5CR)] and phenylpropanoid pathway [phenylalanine ammonia-lyase (PAL)] but Cd also specifically increased the expression of PCS1-1 involved in phytochelatin (PC) synthesis. Si exposure influences the expression of numerous genes in a contrasting way in Cd- and Zn-exposed plants. At the leaf level, the accumulation of 122 proteins was affected by Cd, whereas 47 proteins were affected by Zn: only 16 proteins were affected by both Cd and Zn. The number of proteins affected due to Si exposure (27) alone was by far lower, and 12 were not modified by heavy metal treatment while no common protein seemed to be modified by both CdSi and ZnSi treatment. It is concluded that Cd and Zn had a clear different impact on plant metabolism and that Si confers a specific physiological status to stressed plants, with quite distinct impacts on hemp proteome depending on the considered heavy metal.

ID: 35907072
Title: Silicon reduces zinc absorption and triggers oxidative tolerance processes without impacting growth in young plants of hemp (Cannabis sativa L.).
Abstract: Hemp (Cannabis sativa L.) is a promising crop for non-food agricultural production on soils contaminated by moderate doses of heavy metals, while silicon, as a beneficial element, is frequently reported to improve stressed plant behavior. Using a hydroponic system, plants of Cannabis sativa (cv. Santhica 27) were exposed for 1 week to 100 µM Zn in the presence or absence of 2 mM Si. Zinc accumulated in all plant organs but was mainly sequestered in the roots. Additional Si reduced Zn absorption but had no impact on Zn translocation. Zn accumulation had a slight negative impact on leaf number, stem length, and chlorophyll content, and additional Si did not mitigate these symptoms. Exogenous Si reduced the Zn-induced membrane lipid peroxidation (assessed by malondialdehyde quantification) and increased the total antioxidant activities estimated by the FRAP index. In the absence of Si, leaf phytochelatin and total glutathione were the highest in Zn-treated plants and Si significantly decreased their concentrations.

ID: 36145765
Title: Proanthocyanidins Alleviate Cadmium Stress in Industrial Hemp (Cannabis sativa L.).
Abstract: Industrial hemp (Cannabis sativa L.), an annual herbaceous cash crop, is widely used for the remediation of heavy metal-contaminated soils due to its short growth cycle, high tolerance, high biomass, and lack of susceptibility to transfer heavy metals into the human food chain. In this study, a significant increase in proanthocyanidins was found in Yunnan hemp no. 1 after cadmium stress. Proanthocyanidins are presumed to be a key secondary metabolite for cadmium stress mitigation. Therefore, to investigate the effect of proanthocyanidins on industrial hemp under cadmium stress, four experimental treatments were set up: normal environment, cadmium stress, proanthocyanidin treatment, and cadmium stress after pretreatment with proanthocyanidins. The phenotypes from the different treatments were compared. The experimental results showed that pretreatment with proanthocyanidins significantly alleviated cadmium toxicity in industrial hemp. The transcriptome and metabolome of industrial hemp were evaluated in the different treatments. Proanthocyanidin treatment and cadmium stress in industrial hemp mainly affected gene expression in metabolic pathways associated with glutathione metabolism, phenylpropanoids, and photosynthesis, which in turn altered the metabolite content in metabolic pathways of phenylalanine, vitamin metabolism, and carotenoid synthesis. The combined transcriptomic and metabolomic analysis revealed that proanthocyanidins mitigated cadmium toxicity by enhancing photosynthesis, secondary metabolite synthesis, and antioxidant synthesis. In addition, exogenous proanthocyanidins and cadmium ions acted simultaneously on EDS1 to induce the production of large amounts of salicylic acid in the plant. Finally, overexpression of CsANR and CsLAR, key genes for proanthocyanidins synthesis in industrial hemp, was established in Arabidopsis plants. The corresponding plants were subjected to cadmium stress, and the results showed that CsLAR transgenic plants were more tolerant to cadmium than the CsANR transgenic and wild-type Arabidopsis plants. The results showed that salicylic acid and jasmonic acid were increased in Arabidopsis overexpressing CsLAR compared to AT wild-type Arabidopsis, and levels of secondary metabolites were significantly higher in Arabidopsis overexpressing CsLAR than in AT wild-type Arabidopsis. These results revealed how proanthocyanidins alleviated cadmium stress and laid the foundation for breeding industrial hemp varieties with higher levels of proanthocyanidins and greater tolerance.

ID: 36181931
Title: Rhizophagus irregularis enhances tolerance to cadmium stress by altering host plant hemp (Cannabis sativa L.) photosynthetic properties.
Abstract: Arbuscular mycorrhizal fungi (AMF) are widespread and specialized soil symbiotic fungi, and the establishment of their symbiotic system is of great importance for adversity adaptation. To reveal the growth and photosynthetic characteristics of AMF-crop symbionts in response to heavy metal stress, this experiment investigated the effects of Rhizophagus irregularis (Ri) inoculation on the growth, photosynthetic gas exchange parameters, and chlorophyll fluorescence characteristics of hemp (Cannabis sativa L.) at a Cd concentration of 80 mg/kg. The results showed that (1) under Cd stress, the biomass of each plant structure in the Ri treatment was significantly higher than that in the noninoculation treatment (P < 0.05); (2) under Cd stress, the transpiration rate, stomatal conductance, net photosynthetic rate, PSII efficiency, apparent electron transport rate and photochemical quenching coefficient of the Ri inoculation group reached a maximum, with increases ranging from 1% to 28%; (3) inoculation of Ri significantly reduced Cd enrichment in leaves, which in turn significantly increased the transpiration rate, stomatal conductance, electron transfer rate, net photosynthetic rate and photosynthetic intensity, protecting PSII (P < 0.05); and (4) by measuring the light response curves of different treatments, the light saturation points of hemp inoculated with the Ri treatment reached 1448.4 μmol/m2/s, and the optical compensation point reached 24.0 μmol/m2/s under Cd stress. The Ri-hemp symbiont demonstrated high adaptability to weak light and high utilization efficiency of strong light under Cd stress. Our study showed that Ri-hemp symbiosis improves adaptation to Cd stress and promotes plant growth by regulating the photosynthetic gas exchange parameters and chlorophyll fluorescence parameters of plants. The Ri-hemp symbiosis is a promising technology for improving the productivity of Cd-contaminated soil.

ID: 36448248
Title: Cadmium-resistant Streptomyces stimulates phytoextraction potential of Crotalaria juncea L. in cadmium-polluted soil.
Abstract: This work evaluated the competence of two strains of cadmium (Cd)-resistant Streptomyces, namely Streptomyces rapamycinicus K5PN1, an indole-3-acetic acid (IAA) producer, and Streptomyces cyaneus 11-10SHTh, a siderophore producer on promoting Cd phytoextraction by sunn hemp. The results showed that S. rapamycinicus improved root elongation of sunn hemp seedlings under Cd stress conditions. S. rapamycinicus and S. cyaneus were colonized on the root surface of sunn hemp at concentrations of 2.3 × 104 and 6.4 × 103 CFU g-1 root fresh weight, respectively. The results of pot-culture experiments showed that S. rapamycinicus increased the root and shoot lengths, and dry biomass of sunn hemp planted in high Cd-contaminated soil. The Cd concentration in the leaves of sunn hemp inoculated with S. cyaneus (73.82 ± 2.20 mg kg-1 plant dry wt) was higher than that of plants with S. rapamycinicus inoculation and the uninoculated control. The phytoextraction of Cd by sunn hemp was significantly increased with Cd-resistant Streptomyces inoculation. In conclusion, both strains of Cd-resistant Streptomyces had potential on enhancing Cd phytoextraction efficiency of sunn hemp. Our study suggests the application of Cd-resistant Streptomyces can improve Cd phytoextraction by sunn hemp for restoration of Cd-polluted sites. Our study demonstrated the potential of two strains of Cd-resistant Streptomyces to stimulate Cd phytoextraction from soil by sunn hemp. Cadmium-resistant Streptomyces strongly stimulated Cd uptake and accumulation in sunn hemp planted in high level of Cd-polluted soil, supporting sunn hemp to be a superior Cd accumulator.

ID: 36637648
Title: Industrial hemp (Cannabis sativa L.) field cultivation in a phytoattenuation strategy and valorization potential of the fibers for textile production.
Abstract: This paper evaluates the valorization potential of industrial hemp (Cannabis sativa L.) fibers produced on HM-contaminated soil as a safe feedstock for the textile industry. The chosen strategy was phytoattenuation, which combines the progressive soil quality improvement of contaminated land using phytoremediation techniques with the production of safe non-food biomass. A field experiment was set up with two hemp cultivars on a site contaminated with Cd, Pb, and Zn and on a nearby site containing clean soil as a control. Stem height and diameter were analyzed, as well as stem and fiber yield and the HM concentrations in the fibers, which were compared to legal safety standards and toxicity thresholds used in the textile industry. The hemp cultivar Carmagnola Selected (CS) had a significantly higher stem and bigger stem diameter compared to cultivar USO 31 on both sites. Stem yields showed a decrease of 30% and 50%, respectively, for both hemp cultivars grown on the contaminated site. However, the stem yield of CS growing on the contaminated site was similar to the stem yield of USO 31 growing on the control site, indicating that hemp cultivation on contaminated soil can be economically viable. Total and extractable Cd, Pb, and Zn fiber concentrations were far below the toxicity standards for textile production purposes. These results are promising in terms of the potential valorization of contaminated land with hemp cultivation and the development of a non-food value chain within a phytoattenuation strategy.

ID: 36668731
Title: Phytoremediation: A Novel Approach of Bast Fiber Plants (Hemp, Kenaf, Jute and Flax) for Heavy Metals Decontamination in Soil-Review.
Abstract: Heavy metal pollution in the environment is a major concern for humans as it is non-biodegradable and can have a lot of effects on the environment, humans as well as plants. At present, a solution to this problem is suggested in terms of a new, innovative and eco-friendly technology known as phytoremediation. Bast fiber plants are typically non-edible crops that have a short life cycle. It is one of the significant crops that has attracted interest for many industrial uses because of its constant fiber supply and ease of maintenance. Due to its low maintenance requirements with minimum economic investment, bast fiber plants have been widely used in phytoremediation. Nevertheless, these plants have the ability to extract metals from the soil through their deep roots, combined with their commercial prospects, making them an ideal candidate as a profit-yielding crop for phytoremediation purposes. Therefore, a comprehensive review is needed for a better understanding of the morphology and phytoremediation mechanism of four commonly bast fiber plants, such as hemp (Cannabis sativa), kenaf (Hibiscus cannabinus), jute (Corchorus olitorius) and Flax (Linum usitatissimum). This review article summarizes the existing research on the phytoremediation potential of these plants grown in different toxic pollutants such as Lead (Pb), Cadmium (Cd) and Zinc (Zn). This work also discusses several aids including natural and chemical amendments to improve phytoremediation. The role of these amendments in the bioavailability of contaminants, their uptake, translocation and bioaccumulation, as well as their effect on plant growth and development, has been highlighted in this paper. This paper helps in identifying, comparing and addressing the recent achievements of bast fiber plants for the phytoremediation of heavy metals in contaminated soil.

ID: 37080470
Title: Arbuscular mycorrhizal fungi influence the uptake of cadmium in industrial hemp (Cannabis sativa L.).
Abstract: Phytoremediation is currently a more environmentally friendly and economical measure for the remediation of cadmium (Cd) contaminated soil. Heavy metal-resistant plant species, Cannabis sativa L. was inoculated with Rhizophagus irregularis to investigate the mechanisms of mycorrhizal in improving the Cd remediation ability of C. sativa. The results showed that after inoculation with R. irregularis, C. sativa root Cd contents increased significantly, and leaf Cd enrichment decreased significantly. At the transcriptional level, R. irregularis down-regulated the expression of the ABC transporter family but up-regulated differentially expressed genes regulating low molecular weight organic acids. The levels of malic acid, citric acid, and lactic acid were significantly increased in the rhizosphere soil, and they were significantly and strongly related to oxidizable Cd concentrations. Then citric acid levels were considerably and positively connected to exchangeable Cd concentrations. Our findings revealed that through regulating the movement of root molecules, arbuscular mycorrhizal fungus enhanced the heavy metal tolerance of C. sativa even more, meanwhile, they changed the Cd chemical forms by altering the composition of low molecular weight organic acids, which in turn affected soil Cd bioavailability.

ID: 37324677
Title: Cadmium exposure is associated with increased transcript abundance of multiple heavy metal associated transporter genes in roots of hemp (Cannabis sativa L.).
Abstract: Industrial hemp (Cannabis sativa L.) has demonstrated promise for phytoremediation due to an extensive root system, large biomass, and ability to survive under relatively high levels of heavy metals. However, little research has been conducted to determine the impact of heavy metal uptake in hemp grown for medicinal use. This study evaluated the potential for cadmium (Cd) uptake and its impact on growth, physiological responses, and transcript expression of metal transporter genes in a hemp variety grown for flower production. The cultivar 'Purple Tiger' was exposed to 0, 2.5, 10, and 25 mg·L-1 Cd in a greenhouse hydroponic study in two independent experiments. Plants exposed to 25 mg·L-1 Cd displayed stunted plant growth characteristics, reduced photochemical efficiency, and premature senescence suggesting Cd toxicity. At the two lower concentrations of Cd (2.5 and 10 mg·L-1 Cd), plant height, biomass, and photochemical efficiency were not affected, with chlorophyll content index (CCI) being slightly lower at 10 mg·L-1 Cd, compared to 2.5 mg·L-1 Cd. There were no consistent differences between the two experiments in total cannabidiol (CDB) and tetrahydrocannabinol (THC) concentrations in flower tissues at 2.5 and 10 mg·L-1 Cd, compared to the control treatment. Root tissue accumulated the highest amount of Cd compared to other tissues for all the Cd treatments, suggesting preferential root sequestration of this heavy metal in hemp. Transcript abundance analysis of heavy metal-associated (HMA) transporter genes suggested that all seven members of this gene family are expressed in hemp, albeit with higher expression in the roots than in the leaves. In roots, CsHMA3 was up-regulated at 45 and 68 d after treatment (DAT), and CsHMA1, CsHMA4, and CsHMA5 were upregulated only under long term Cd stress at 68 DAT, at 10 mg·L-1 Cd. Results suggest that expression of multiple HMA transporter genes in the root tissue may be upregulated in hemp exposed to 10 mg·L-1 Cd in a nutrient solution. These transporters could be involved in Cd uptake in the roots via regulating its transport and sequestration, and xylem loading for long distance transport of Cd to shoot, leaf, and flower tissues.

ID: 37884708
Title: Industrial hemp (Cannabis sativa L.)-a valuable alternative crop for growing in agricultural soils contaminated with heavy metals.
Abstract: Hemp (Cannabis sativa L.) is a multiuse plant, which has been abundantly studied for phytoremediation purposes in recent years. The majority of experiments were performed in greenhouses with potted plants where hemp showed promising results. Only few studies tested hemp on site in heavy metal-polluted agricultural soil in real environmental conditions and practical assessments of hemp phytoremediation feasibility are lacking. We conducted a comprehensive study using 2 legal industrial hemp varieties (Futura 75 and Tisza) at three differently polluted locations (heavily polluted location, HP; moderately polluted location, MP; and slightly polluted location, SP) in the heavy metal contaminated Celje valley in Slovenia and determined the content of Pb, Zn, and Cd in 5 plant organs/tissues. The yield of each organ/tissue was determined as well to enable us to calculate the phytoremediation potential (PP). On average, plants grown in the HP location accumulated the highest values of all examined elements, followed by plants from the MP location and plants from the SP location, showing that the content of heavy metals in soil influences the accumulation in plants. Accumulation of Pb/Zn/Cd by plant organs/tissues was distributed in the following order: inflorescences (Pb-4.10/Zn-92.8/Cd-0.50 mg/kg) > seeds (Pb-1.79/Zn-92.6/Cd-0.27 mg/kg) > roots (Pb-1.15/Zn-15.0/Cd-0.44 mg/kg) > stem bark (Pb-0.42/Zn-12.4/Cd-0.23 mg/kg) > stem woody core (Pb-0.34/Zn-4.6/Cd-0.15 mg/kg). The only exception was for Cd, where roots accumulated a higher value than seed, yet lower than inflorescences. PP was calculated by multiplying hemp tissue/organ yield by the relative concentrations of heavy metal. The highest PP for Pb and Cd were achieved at the HP location (3.80 and 0.23 g/ha/vegetation period). On the other hand, tissue/organ yield was more important for high PP of Zn, where the SP location reached the highest PP for Zn (148.5 g/ha/vegetation period) due to the highest yields. Only seeds from HP and MP locations accumulated a too high content of Pb; otherwise, all other fibers and seeds can be safely used in the textile and food industry. Results of this study showed that hemp cannot be considered an efficient plant for the phytomanagement of contaminated areas. Nevertheless, hemp cultivation in heavy metal-polluted agricultural soils seems feasible since the majority of tissues/organs were not contaminated and different products can be obtained from various parts of the hemp plant.

ID: 38081533
Title: The comprehensive review about elements accumulation in industrial hemp (Cannabis sativa L.).
Abstract: Cannabis sativa L., commonly known as industrial hemp, is a versatile plant with applications ranging from medicinal to agricultural and industrial uses. Despite its benefits, there is a notable gap in regulatory toxicology, in understanding the extent of element accumulation in hemp, which is critical due to its ability to absorb various elements from the soil, including heavy metals (Pb, Cd, Hg, and As), uptakes potential toxic elements (e.g., Sb, Sn, Sr, Bi, Tl), problematic elements (Ni, Cr, Co), and essential elements (Zn, Cu, Fe, Mn). The paper aims to enrich current understandings by offering a comprehensive analysis of elements absorption in industrial hemp. This study emphasizes the potential health risks linked with hemp consumption including regulatory toxicology aspects: limits, Permitted Daily Exposures (PDE), recommendations in different countries and from different agencies/bodies (like the WHO and the EU) based on route of administration, jurisdiction and actual literature review. This review contributes significantly to the knowledge base on hemp safety, serving as a valuable resource for researchers, regulatory bodies, and industry stakeholders.

ID: 39018846
Title: Elucidating the phytoremediation potentials and ecophysiological mechanisms of indicator plants in the industrial polluted region.
Abstract: The integrity of natural ecosystems, particularly in the Global South, is increasingly compromised by industrial contaminants. Our study examines the growth of plant species adapted to ecosystems impacted by heavy metal pollution, specifically focusing on their phytoremediation capabilities and tolerance to contaminants. The potential of pollution-tolerant species was evaluated in the industrial subtropical wetland of Sialkot, Pakistan. Employing quantitative ecological methods, data on vegetation, phytosociological attributes, and soil properties were gathered from 450 plots across different pollution gradients. The study pinpointed 17 key indicator species tolerating high heavy metal pollution out of 182 surveyed, using a combination of Indicator Species Analysis (ISA) and the Importance Value Index (IVI). These species demonstrated diverse capacities to extract, stabilize, and accumulate heavy metals (Cr, Zn, Cu, As, Cd, Ni, Hg, and Pb) across varying pollution zones. Notably, Cannabis sativa demonstrated substantial phytoextraction of Zn and Cd, with concentrations reaching 1977.25 μg/g and 1362.78 μg/g, respectively. Arundo donax showed marked hyperaccumulation of Cd, peaking at 410.531 μg/g. Achyranthes aspera was remarkable for its extraction and accumulation of Ni and Cu, with concentrations of 242.412 μg/g and 77.2997 μg/g, respectively. Physiological changes, such as increased proline levels in Cannabis sativa and Achyranthes aspera reaching 39.041 μg/g and 27.523 μg/g under high metal concentrations, indicated adaptation to metal stress. Declines in chlorophyll and carotenoid levels were also observed as metal contamination increased, with up to 35% reductions in some species. These findings underscore the potential efficacy of selected plant species in phytoremediation and highlight the importance of physiological responses in their tolerance to metals, providing valuable information for targeted remediation strategies in polluted ecosystems and improving environmental management and sustainable practices.

ID: 39094452
Title: Study of plasma activated water effect on heavy metal bioaccumulation by Cannabis sativa Using Laser-Induced Breakdown Spectroscopy.
Abstract: Contamination of the environment with toxic metals such as cadmium or lead is a worldwide issue. The accumulator of metals Cannabis sativa L. has potential to be utilized in phytoremediation, which is an environmentally friendly way of soil decontamination. Novel non-thermal plasma-based technologies may be a helpful tool in this process. Plasma activated water (PAW), prepared by contact of gaseous plasma with water, contains reactive oxygen and nitrogen species, which enhance the growth of plants. In this study, C. sativa was grown in a short-term toxicity test in a medium which consisted of plasma activated water prepared by dielectric barrier discharge with liquid electrode and different concentrations of cadmium or lead. Application of PAW on heavy metal contaminated C. sativa resulted in increased growth under Pb contamination as was determined by ecotoxicology tests. Furthermore, the PAW influence on the bioaccumulation of these metals as well as the influence on the nutrient composition of plants was studied primarily by applying Laser-induced breakdown spectroscopy (LIBS). The LIBS elemental maps show that C. sativa accumulates heavy metals mainly in the roots. The results present a new proof-of-concept in which PAW could be used to improve the growth of plants in heavy metal contaminated environment, while LIBS can be implemented to study the phytoremediation efficiency.

ID: 39701391
Title: Chitooligosaccharide application enhanced the growth and phytoremediation efficiency of industrial hemp in Cd-contaminated soils.
Abstract: Hemp has been widely used for cadmium (Cd) remediation. However, its remediation efficiency needs to be improved. Chitooligosaccharides can enhance plant resistance and growth; however, their effects on hemp for Cd-remediation remain unclear. Herein, a greenhouse pot experiment was conducted to investigate the effects of three doses (0, 22.5, and 45 μg m-2) of chitooligosaccharides (COS), chitin-oligosaccharides (NACOS), and hetero-chitooligosaccharides (HTCOS) on the growth and Cd-remediation efficiency of hemp. Results showed that chitooligosaccharides promoted the antioxidant system and aerial biomass (maximum 84 %) depending on doses and types. COS (22.5 μg m-2 under 60 mg cadmium kg-1 soil), NACOS, and HTCOS significantly elevated the Cd concentration in hemp. Consequently, NACOS and HTCOS (45 μg m-2) significantly increased the average Cd removal up to 61 % and 81 %, respectively, compared with the control. Therefore, spraying chitooligosaccharides can enhance growth and phytoremediation efficiency of hemp by elevating aerial biomass and cadmium concentration of hemp.

ID: 39997905
Title: The Tolerance Differences of Two Industrial Hemp Varieties Under Lead (Pb) Stress.
Abstract: Industrial hemp is a crop with a high tolerance and accumulation of lead (Pb). Improving the Pb tolerance and accumulation capacity of industrial hemp is of great scientific and practical importance. This study utilized a pot with soil contaminated with Pb to investigate the differences in Pb tolerance between two industrial hemp varieties, Yunma1 (YM) and Shaanxi Industrial Hemp (SM), under Pb stress. The results indicated that Pb mainly accumulates in the roots of YM and SM (70-80%), with YM having a higher Pb accumulation than SM. It is worth nothing that under high Pb concentration conditions (5000 mg/kg), the Pb accumulation capacity of YM is twice that of SM. Accumulation characteristics of Pb in different plant tissues followed the pattern: roots > stems > leaves > fibers > seeds. In YM, approximately 70% of the absorbed Pb was fixed in the roots and 30% was transported to the above-ground parts. In contrast, SM transported more than 50% of absorbed Pb by roots to the above-ground areas, causing some degree of damage to stems and leaves. Even when Pb concentrations exceed 4000 mg/kg, YM exhibits strong tolerance (tolerance index greater than 90%), with normal growth and no signs of toxicity. However, SM showed a tolerance level of < 50% at high Pb concentrations, with significant heavy metal toxicity symptoms in the above-ground areas. These results provide important information for the remediation of Pb contaminated soils in mining areas.

ID: 40803067
Title: Kenaf biochar enhances heavy metal phytostabilization and growth of industrial hemp (Cannabis sativa L.) using multi-metal contaminated mining site soils.
Abstract: Heavy-metal (HM) contamination in agricultural soils poses significant risks to ecosystems and human health. Eco-friendly solutions such as biochar application and phytoremediation have emerged as promising approaches for HM immobilization. Industrial hemp (Cannabis sativa L.), a fast-growing fiber crop with high biomass yield and strong HM stress tolerance, demonstrates significant potential for phytoremediation. In the present study, kenaf biochar (KBC) demonstrated multi-layer chemisorption behavior within a ternary HM system, exhibiting high affinity for HMs, especially for Cd2+ and Zn2+. A controlled pot experiment was performed to examine the effectiveness of KBC in reducing the solubility of HMs and limiting their uptake by industrial hemp. The results showed that KBC amendment enhanced soil physicochemical properties, significantly promoting hemp growth and increasing biomass yield. Moreover, KBC enhanced photosynthetic efficiency through upregulation of PetH, LHCB7, and photosynthesis-related genes. Transcriptome analysis revealed the KBC mediated the cascade regulation of MAPK and CDPK signaling pathways, as well as plant hormone signaling pathways, thereby promoting the activation of antioxidant enzyme systems to resist HMs stress. KBC also regulated the genes associated with antioxidant enzyme systems, including superoxide dismutase (SOD) genes and non-enzymatic glutathione-ascorbate (AsA-GSH) cycle, reducing malondialdehyde (MDA) content and reactive oxygen species (ROS) accumulation to restore redox homeostasis. Meanwhile, KBC reduced HM bioavailability in soil, thereby limiting their translocation to plant tissues. It also maintained ion homeostasis by modulating key transporters (ZIP, COPT) and CDPK. This study elucidates the physiological and molecular mechanisms underlying KBC-mediated HM tolerance in industrial hemp, providing valuable insights for sustainable phytoremediation of mining-degraded soils.

ID: 41188503
Title: Physio-biochemical alterations and phytoremediation potential of hemp cultivated in ciprofloxacin (CIP)-contaminated soil: groundbreaking and enduring solution.
Abstract: Hemp (Cannabis sativa L.) is a significant natural fibre employed as reinforcement in sustainable materials and, due to its considerable biomass, wide root system, and resilience to pollutants under harsh environments; it is an outstanding choice for the phytoremediation of multiple contaminants. This study aimed to assess hemp growth, gas exchange properties, antioxidant potential, and phytoremediation ability at varying concentrations of ciprofloxacin (0, 50, 100, 150, and 200 mg kg-1) in a controlled glasshouse environment. The results indicate that hemp can tolerate Ciprofloxacin (CIP) concentrations up to 150 mg kg-1 without substantial reductions in biomass and growth parameters; however, higher CIP levels, namely 200 mg kg-1, lead to considerable drops in plant biomass and growth. The gas exchange properties and photosynthetic pigment levels of hemp leaves decreased as the CIP in the soil rose. Moreover, elevated CIP levels in soil induced lipid peroxidation via malondialdehyde level enhancement in hemp leaves. Elevated levels of CIP induced oxidative damage, antioxidants, including peroxidase and superoxide dismutase, function to neutralize ROS produced by oxidative stress. This study examined the CIP amounts in several plant elements such as fibres, stem core, leaves and roots at 4 different phases: 28-, 55-, 110- and 135-days post-sowing. The study's findings reveal that, throughout the early growth stages, CIP predominantly accumulated in the subterranean regions of the crop, with limited translocation to the aerial areas. Conversely, at full maturity (135 days post-sowing), it was shown that the majority of CIP was translocated to the plant's above-ground structures, with no accumulation in subterranean areas. The results demonstrate a progressive increase in CIP absorption in relation to heightened CIP concentrations in soil, suggesting that hemp could function as an effective phytoremediation bioresource and agent in contaminated soils.

ID: 41309806
Title: Tissue residue depletion of cannabinoids in cattle administered industrial hemp inflorescence.
Abstract: Despite interest in using industrial hemp (IH) in cattle feed, there are minimal safety data on tissues from exposed cattle. This study sought to describe cannabinoid tissue concentrations, estimate withdrawal times for cattle exposed to IH inflorescence, and generate human exposure estimates for Δ9-tetrahydrocannabinol and cannabidiol. Twenty male Holsteins received IH inflorescence orally at 4.2 mg/kg/d cannabidiolic acid for 14 d. Liver, kidney, muscle, and adipose were collected at 1, 2, 3, 5, and 8 days after IH administration and analyzed for cannabinoids using liquid chromatography mass spectrometry. Withdrawal intervals and target tissues were selected based on the slowest-depleting cannabinoid. ∆9-tetrahydrocannabinol was detected in liver, kidney, and adipose and cannabidiol in all tissues. Withdrawal intervals for liver, kidney, muscle, and adipose were 68, 21, 39, and 154 d, respectively. Adipose was selected as the target tissue and cannabidiol the marker residue. Exposure estimates generated using data from this study revealed that newborns exceeded the lowest published global toxicity threshold of 1 µg/kg Δ9-tetrahydrocannabinol. Additional work should determine safe levels of cannabinoid exposure in vulnerable populations (i.e. children and adolescents). Our results will inform future discussions regarding the inclusion of IH in cattle feed.

ID: 41372766
Title: Comparison of selected metals in the fillers of 14 commercial hemp cigarette brands to commercial tobacco cigarettes.
Abstract: Cannabis sativa L. containing < 0.3% delta-9 tetrahydrocannabinol (THC) is currently defined as hemp. Many different legal products in the United States now contain hemp and are marketed for their cannabinoid effects, as an alternative to tobacco products, or even as an aid for tobacco smoking cessation. The hemp cigarettes analyzed have similar designs to tobacco cigarettes with a filter and filler wrapped in paper. Cannabis sativa, like tobacco (Nicotiana tabacum), is a hyperaccumulator of metals. Currently, no publications have reported analyses of metals in these cigarette-like products. Hemp and cannabidiol (CBD) products are increasing in popularity. Thus, reporting the metal concentrations from a variety of hemp cigarette brands can help assess the potential for harmful exposures. We analyzed the hemp filler in 14 commercial brands for beryllium (Be), chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), arsenic (As), cadmium (Cd), lead (Pb), and uranium (U) content.The hemp cigarette filler metals concentrations are compared to previously published metals levels in tobacco cigarette and little cigar filler. NIST Reference Material (RM) 8210 Hemp Plant was also analyzed to assess and confirm analytical accuracy. Of note, all hemp cigarette filler cadmium concentrations were below our lowest reportable level, and statistically lower than our previously published U.S. tobacco cigarettes and little cigars filler. The other metal concentration ranges were similar to previous tobacco cigarettes and little cigars results, although mean concentrations were statistically different in many cases. Different states have testing requirements with action limits for selected metals concentrations in Cannabis sativa L. Several hemp cigarette brands had chromium, nickel, arsenic, and lead concentrations that were above some state action limits.

ID: 41383740
Title: Bioprotective role of Cladosporium tenuissimum counteracting heavy metal (chromium) stress in Triticum aestivum L.
Abstract: Heavy metal pollution, particularly from chromium (Cr), poses a significant threat to plant development and soil health. This study evaluated the efficacy of the rhizospheric fungus strain Cladosporium tenuissimum, isolated from the rhizosphere of Cannabis sativa, in enhancing the early growth and physiological resilience of Triticum aestivum L. (wheat) under chromium-induced stress. The strain Cladosporium tenuissimum demonstrated tolerance through substantial biomass retention in Czapek-Dox medium at chromium concentrations between 30 and 90 mg/L, mitigated the decrease in carotenoid and chlorophyll pigments, enhanced protein and sugar levels, and significantly promoted root and shoot growth in wheat under chromium stress. Additionally, fungal therapy reduced proline accumulation and restored indole-3-acetic acid (IAA) levels, indicating improved hormonal balance and reduced stress levels. Furthermore, Cladosporium tenuissimum (C. tenuissimum) maintained membrane integrity and regulated excess flavonoids by reducing electrolyte leakage. Under chromium stress, the activities of antioxidant enzymes were elevated; however, fungal inoculation moderated these activities to some extent. These findings indicate that C. tenuissimum may serve as a bioprotective agent, enhancing plant tolerance and mitigating Cr toxicity by regulating metabolic processes, physiological responses, and antioxidant activity.

ID: 41501645
Title: A plant-derived compound activating agent enhances cadmium phytoextraction by Lantana Camara L.
Abstract: Agent-assisted phytoextraction is an attractive strategy to remove heavy metals from soil. However, there is a lack of effective and sustainable agents. In this study, 10 types of plant extracts were extracted and selected to combined with N, N-bis (carboxymethyl) glutamic acid (GLDA) to prepare the compound activating agent, and its effectiveness and potential risk in enhancing Cd phytoextraction by Lantana camara L. (L. camara) were evaluated. Among the 10 plant extracts, Houttuynia cordata Thunb. extract (HC) showed the highest Cd extraction ability (24.58%). When combined with GLDA (0.9%) in a 1:1 volume ratio, the compound activating agent removed Cd most effectively (79.23%) from soil. In the pot experiment, this agent increased the shoot biomass, Cd concentration, and accumulation in L. camara by 17.45%, 71.43%, and 100.42%, respectively, compared with the Cd treatment. Additionally, soil DOC (+ 17.47%) and available Cd (+ 34.05%) were significantly increased vs. Cd treatment. Acid soluble Cd increased significantly, while the reducible and oxidizable Cd fractions decreased. In the soil column experiment, leached Cd from soils treated with this agent treatment was significantly lower than from EDTA treated soils. Collectively, the compound activating agent enhanced Cd phytoextraction by L. camara through its activation effect and increased soil DOC, which promoted the conversion of oxidizable/reducible Cd to acid soluble Cd and mobilized soil Cd for plant uptake. Thus, the HC extract combined with GLDA compound activating agent is a promising enhancer for Cd phytoextraction.

ID: 41516899
Title: In Situ Synthesis of ZnO Nanoparticles Using Soy Protein Isolate for Sustainable and Multifunctional Finishing of Hemp Fabrics.
Abstract: This study presents an environmentally sustainable finishing approach for hemp fabrics by combining soy protein isolate (SPI) pretreatment with an in situ infrared (IR)-assisted synthesis of zinc oxide nanoparticles (ZnO NPs). IR heating was employed to reduce energy consumption while promoting efficient nanoparticle formation compared to conventional thermal processing, while SPI acted as a bio-based stabilizer to enable uniform ZnO NP distribution on the fabric surface. Transmission electron microscopy revealed predominantly spherical to polyhedral ZnO NPs with minimal agglomeration, and X-ray diffraction confirmed their characteristic wurtzite crystalline structure. Scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy mapping further verified the homogeneous deposition of ZnO NPs on hemp fibers. The treated fabrics exhibited multifunctional performance, showing significantly enhanced ultraviolet (UV) protection with a UV protection factor (UPF) of 50+ compared with untreated hemp. Antibacterial activity against Staphylococcus aureus and Escherichia coli was confirmed by the AATCC TM147 test, while a quantitative AATCC TM100 assessment demonstrated an excellent antibacterial efficiency of 99.99% bacterial reduction against S. aureus. Additionally, the incorporation of 2 wt% SPI significantly improved fabric hydrophilicity and wettability. Overall, this work demonstrates a green and effective strategy for producing antibacterial and UV-protective hemp textiles.

ID: 41614606
Title: Field-grown hemp treated with humic/fulvic acids and arbuscular mycorrhizal fungi for phytomanaging a metal-contaminated agricultural soil.
Abstract: Industrial hemp offers several advantages for phytomanaging metal(loid)-contaminated soils as it can provide valuable biomass notably for bioenergy while accumulating some metals (i.e., Cd and Zn) in its shoots. In a previous pot study humic/fulvic acids (HFA) incorporated into the soil with arbuscular mycorrhizal fungi (AMF) enhanced hemp growth. This study assessed the biostimulant effect of HFA, alone or paired with AMF (HFAxAMF), on the shoot yield and shoot Cd, Pb and Zn uptakes in a 2-year field trial in view of producing clean, renewable liquid biofuels. The trial (0.07 ha) was carried out at a contaminated agricultural field in a randomized split-plot design (nine blocks). Cannabis sativa L. was sown at a density of 173 000 plants ha-1. Effects of HFA and HFAxAMF treatments on the behavior of metals and plants were compared to an unamended one. Hemp produced on average 10.7 (year 1)-14.5 (year 2) t DW ha-1 despite a severe drought in year 1. Neither HFA nor HFAxAMF treatments enhanced shoot yield. Shoot Cd, Pb and Zn uptakes reached 9.9, 230, and 869 g ha-1 year-1, respectively. In year 2, shoot Cd uptake improved under all treatments and the 0.01 M Ca(NO3)2-extractable soil Cd, Pb and Zn concentrations at harvest decreased by 95, 79 and 96%, respectively. Hemp was a relevant plant species for phytomanaging this metal-contaminated soil under current climatic constraints. The potential bioethanol yield was estimated in the 3851-6481 L ha-1 range. Overall, hemp can simultaneously reduce soil metal availability while producing a biomass convertible into liquid biofuels. This highlights its strong potential as a dual-purpose crop for sustainable and progressive phytoremediation and renewable energy production. This study investigates the effects of humic/fulvic acids (HFA), applied alone or paired with AMF (HFAxAMF) on Cd, Pb and Zn uptake by hemp shoots and shoot yield in a 2-year field trial. The work aimed at producing a biomass usable for renewable liquid biofuels, while using hemp for managing contaminated soils under current climatic conditions in the vicinity of the former Metaleurop smelter.

ID: 41731563
Title: Comparative analysis of metals, pesticides, mycotoxins, microbial contaminants and THC potency in illegal and regulated cannabis inflorescences in Canada.
Abstract: BACKGROUND: Following the legalization of recreational cannabis in Canada under the Cannabis Act (2018), regulatory frameworks were implemented to ensure product safety, quality, and consistency within the legal market. Previous studies revealed significantly greater pesticide contamination in illegal cannabis than in legal products. In light of these findings, the present study expands contaminant surveillance to include the quantification of Δ⁹-tetrahydrocannabinol (THC) and a broader range of potential toxicants, including metals, pesticides, mycotoxins, and microbial agents. METHODS: Fifty legal cannabis products were purchased across Canadian provinces, and 50 illegal samples were obtained via law enforcement seizures. All the samples were tested via validated, accredited/attested methods. THC content was assessed using LC-UV-MS. Pesticides were analyzed via LC-MS/MS and GC-MS/MS; metals via ICP-MS/MS; mycotoxins via LC-MS/MS; and microbial contamination using MALDI-TOF. RESULTS: THC levels in 48% of legal products deviated by more than 20% from their labeled concentrations. Microbiological testing revealed that 20% of legal products exceeded the European Pharmacopoeia microbial limits, prompting appropriate compliance and enforcement measures to address each of these cases. In contrast, 55% of the illegal products exceeded the aerobic plate count thresholds, and 73% surpassed the yeast and mold limits. Mycotoxins were undetected in legal products but were present in 12% of illegal samples. Pesticide residues were found at trace levels (0.01 µg/g) for myclobutanil and dichlobenil in two legal samples, whereas 94% of illegal samples contained pesticides, averaging 3.4 compounds per sample across 24 unique active ingredients. Metal analysis revealed higher levels of arsenic, cadmium, lead, and mercury in illegal products than in their legal counterparts. However, legal samples presented higher chromium concentrations, with peak values approximately threefold greater than those observed in illegal cannabis. The concentrations of arsenic, barium, chromium, copper, molybdenum, nickel, and vanadium exceeded the inhalation concentration limits found in Table 2 of USP <232> of the United States Pharmacopeia (USP) in one or both product categories. CONCLUSION: These findings demonstrate that legal THC levels differ from their label claims as well as that contaminants differ between legal and illegal cannabis products. The results provide evidence to inform regulatory oversight, enhance risk assessment efforts, and support informed decision-making by consumers and policymakers in the context of a legal cannabis framework.

ID: 41782125
Title: The power of zinc: excess and deficiency of Zn decrease cannabinoids in cannabis without Zn toxicity concerns to consumers.
Abstract: BACKGROUND: Some of the mineral nutrients essential for plants are heavy metals, which their consumption may involve health concerns to the consumers. Hence, for safe consumption, optimized fertilization protocol for cannabis plants needs to focus also on minimizing the accumulation of potentially toxic minerals in the inflorescences. Zinc is an essential microelement for plants that has a toxic effect on the human body when consume in high concentration. The present study aimed to understand the drug-type (medical) cannabis plant response to Zn supply, for identifying the optimal Zn supply that balance high quality production with safe product. METHODS: cannabis plants were grown under five Zn levels (0.05, 0.1, 0.35, 1.0, 4.0 mg L− 1) in controlled environment; and morpho-physiology analyses, cannabinoid profile, and ionome-profiling in the plant-organs were conducted. RESULTS: Increased level of Zn supply reduced the relative accumulation of Zn in the inflorescences, and excess Zn was stored in the plant root, and therefore does not impose additional health risk to consumers. Cannabinoid concentrations were highest under 0.35 mgL− 1 Zn supply, and decreased with further increase in Zn supply. The acidic cannabinoids THCA, CBDA, CBCA, CBDVA, THCVA increased with the increase in Zn supply up to 0.1–0.35 mgL− 1 and declined with further increase in Zn. Zn deficiency (under 0.05 mgL− 1 Zn supply) reduced physiological performance, plant growth and inflorescence yield, and stimulated uptake of Zn, P, S, Ca, Fe, and Mn. Symptoms of excess Zn were death of leaf tips; however plant performance was overall not affected by Zn excess. CONCLUSIONS: Excess Zn is retained in the root and excluded from the inflorescence, thereby not imposing health risk to the consumers. The recommended Zn concentration in the fertigation solution that was found to attain highest specialized-metabolite concentrations, and optimal yield and plant performance is 0.35 mgL− 1.

ID: 41847940
Title: Hemp flowers cultivated on a soil contaminated with cadmium, lead and zinc exhibit valorization potential.
Abstract: Industrial hemp (Cannabis sativa L.) is an effective crop for the phytomanagement of lands contaminated with trace metals, demonstrating tolerance to metal toxicity without significant impacts on its value-chain. However, the effects of metal contamination on hemp flowers remain understudied, limiting the assessment of the valorization potential for this valuable plant part. In a greenhouse experiment, we evaluated flower production, cannabinoid content and metal accumulation in hemp grown on a soil contaminated with Cd, Pb and Zn (pseudo-total concentrations: 13.0, 664 and 1048 mg kg-1, respectively). Our results suggest a limited capacity for phytoextraction, with low removal rates for all three metals. Still, hemp flowers presented favorable features that support valorization potential. Both flower biomass and the synthesis of cannabidiol and tetrahydrocannabinol were comparable to plants grown under reference conditions. Notably, inflorescences exhibited the lowest accumulation of Cd and Pb among all plant tissues. Concentrations for these elements were 0.45 and 1.1 mg kg-1 respectively, remaining below most commercial limits for herbal drug products. These findings demonstrate that hemp flowers can be safely produced on metal-contaminated soils, reinforcing the suitability of hemp as a robust and versatile crop for the phytomanagement of legacy metal pollution. This study assesses the valorization potential of hemp flowers grown on a soil presenting elevated levels of cadmium, lead and zinc. Our findings reveal that flowers could potentially be valorized in phytomanagement contexts, and that they accumulated lead and cadmium less than other plant tissues. This is the first time that such observation is made for lead, while the limited existing data for cadmium in that regard is hereby consolidated.

ID: 41996960
Title: Co-pyrolysis of municipal sewage sludge with oak bark and hemp hurd to tailor biochar stability, carbon sequestration and heavy metal immobilization.
Abstract: Municipal sewage sludge (MSS) pyrolysis is constrained by low carbon stability and high heavy metal (HM) content. This study examined whether co-pyrolysis with two underexplored lignocellulosic residues, oak bark (OB) and hemp hurd (HH), could enhance biochar properties relevant to carbon sequestration and environmental safety. MSS was blended with OB or HH at different ratios and pyrolyzed at 400 and 700 °C. The biochars were characterized for physicochemical and textural properties, carbon stability and sequestration, HM fractionation, stability, and ecological risk (MRI). Pyrolysis temperature determined biochar development, while co-substrate type influenced the balance between carbon stabilization and HM immobilization. HH, with higher cellulose and hemicellulose content and lower ash content, promoted devolatilization-driven restructuring of the carbon matrix, enhancing pore development and carbon stability. The highest specific surface area (182 m2/g) was achieved for MSS:HH (50:50) at 700 °C. In contrast, OB, with higher lignin content and greater ash and Ca-rich mineral contribution, favored solid-phase condensation, higher biochar yield, and stronger mineral-mediated stabilization of Cd, Cr, Ni, and Pb. Among the tested blends, MSS:HH (25:75) at 700 °C showed the best carbon sequestration, with the lowest H/Corg (0.20) and O/Corg (0.05), the highest thermostable fraction (88%), the highest long-term carbon storage (0.62 t C/t biochar), and the greatest CO2-equivalent storage (2.3 t CO2/t biochar). All biochars remained within the low-risk MRI category. At 700 °C, Zn decreased by 87% in MSS:HH (25:75) compared to MSS biochar. Strategic feedstock selection enables production of stabilized MSS-derived biochars for carbon sequestration and environmental safety.

ID: 42082743
Title: Chemical characterisation and health implications of atmospheric particulate matter In Ghana's mining hub of Tarkwa.
Abstract: It has now been established that the chemical composition of Particulate Matter (PM) is essential for predicting its associated health endpoints. This paper presents a comprehensive study of the chemical composition and associated health risk of atmospheric particulate matter in the mining city of Tarkwa, Ghana. Total suspended particles (TSP) and PM10 were monitored biweekly for one year using miniVol air samplers for three communities within Tarkwa. The exposed filter samples were divided into two parts and chemically characterised using Scanning Electron Microscope - Energy Dispersive X-ray (SEM-EDX) for elemental particle analysis, and ICP-MS for metal analysis. The risk of non-carcinogenic health impact in the exposed population was computed using the Target Hazard Quotient (THQ), while Positive Matrix Factorisation (PMF) was applied for source identification. The recorded mean TSP mass concentrations for monitoring sites Abekoase (AK), Nsuta (NV), and Tarkwa Banso (TN) were 27.74, 157, and 163 µg/m3, respectively. PM10 mean concentrations were 23.8, 70.85 and 78.64 µg/m3 for AK, NV and TN, respectively. The SEM-EDX analysis revealed particles rich in Si, Al, Na, Zn, Fe, Ca, K, F, O, Mn, and C, with varied mass percentage abundance pointing to Aluminosilicates, Aluminosilicates-soot and likely psilomelane for both TSP and PM10. Varied Metal concentrations in decreasing order of Al > Zn > Mg > Fe > Si > Mn were recorded for TN and NV, while a decreasing order of Mg > Al > Zn > Si > Fe > Mn was recorded for AK. The dry season recorded higher PM-bound metal concentration than the wet season. The metallic concentrations of Fe, Si, Mg and Zn corresponded to a THQ of below unity for both children and adults. However, the estimated THQs for Al and Mn ranged from 2.22 to 19.44 and from 2.64 to 21.78, indicating an adverse health impact on the exposed population. The major PM emission sources were identified as crustal dust, traffic sources and industrial/mining activities. This study establishes a baseline for the study area by providing critical insight into PM pollution, its sources, associated health impacts and priority areas for management intervention. Future investigations of PM chemical composition should extend beyond elemental analysis to include water-soluble fractions, mineralogical characteristics and mechanism of action, particularly in relation to human health, to achieve a more comprehensive understanding of PM properties and behaviour.

ID: 42093032
Title: Feasibility of medicinal cannabis cultivation in outdoor conditions using municipal reclaimed water.
Abstract: Increasing pressure on freshwater resources represents a major challenge for sustainable agricultural production in arid and semi-arid regions. In this context, the use of treated wastewater in agriculture may enhance environmental sustainability and economic efficiency. This study evaluated the yield and safety of outdoor cannabis cultivation irrigated with reclaimed domestic wastewater in an arid Patagonian environment (Argentina). Key metrics included soil and water quality, flower and cannabinoid yield, and chemical and microbiological safety. Soil and water quality were adequate in terms of physicochemical parameters. Escherichia coli in irrigation water at the time of tank filling was 1,700 ± 733 MPN/100 mL. Irrigation was initiated at these concentrations, and E. coli levels declined during subsequent storage in tanks, reaching values below 1,000 MPN/100 mL after approximately 10 days, consistent with the World Health Organization guideline for unrestricted agricultural reuse. E. coli and total coliforms were absent in leaves, flowers, and derived products (herbal oils). Potentially hazardous heavy metals (As, Cd, Co, Cr, Cu, Ni, Pb, and Zn) did not show systematic accumulation in the system. Concentrations in flowers and oils were generally below regulatory standards for edibles; however, Pb levels in dried flowers exceeded established regulatory limits. Dried flower yields were approximately 267.77 ± 34.99 g/plant. Cannabinoid concentrations ranged from 7-14%, comparable to values previously reported for these varieties when cultivated indoors. Overall, the results support the potential of reclaimed wastewater as an irrigation alternative in arid regions, although continued monitoring of contaminants is essential to ensure product safety and regulatory compliance.

ID: 42118791
Title: Strength and leaching characteristics of stabilized ionic rare earth tailings by microbially induced calcium carbonate precipitation.
Abstract: Ion-adsorbed rare earth mining generates extensive tailings sites with compromised structural integrity and heavy metal contamination. This study employed microbially induced carbonate precipitation (MICP) with Sporosarcina pasteurii to solidify and stabilize ion-adsorbed rare-earth tailings. The effects of treatment method, cementation solution (CS) concentration, and heavy metal contamination level on strength characteristics and heavy metal leaching behavior were investigated. Results showed that the unconfined compressive strength (UCS) of samples treated by cyclic grout immersion correlated positively with calcium carbonate (CaCO3) content, reaching a maximum of 770 kPa at 1.00 mol/L CS. Surface CaCO3 content increased with heavy metal concentration, while average CaCO3 content initially increased, then decreased with rising CS concentration. MICP treatment significantly reduced heavy metal leaching. For tailings with initial heavy metal concentrations below 500 mg/kg, leaching concentrations were suppressed below 5 mg/L across all CS concentrations tested. Microstructural analysis revealed that amorphous aggregates composed of calcite, heavy metals, and carbonate coprecipitates served as the primary cementing phase, with heavy metal stabilization achieved through precipitation, adsorption, and CaCO3 encapsulation. These findings demonstrate that MICP technology effectively enhances the mechanical strength of rare earth tailings while immobilizing heavy metals, offering a promising approach for tailings remediation. Further research is needed to address scalability, long-term durability, and performance variability across different tailings types.

ID: 42119894
Title: Phosphorus-solubilizing bacteria and phosphorus-enriched biochar enhance growth, cannabinoid content, and essential oil yield in salt-stressed hemp (Cannabis sativa L.).
Abstract: Soil salinity induces phosphorus (P) deficiency, limiting crop productivity, yet the combined use of phosphorus-solubilizing bacteria (PSB) and phosphorus-enriched biochar (P-biochar) under salinity remains unexplored. This study presents a novel integrated PSB+P-biochar approach to improve growth and secondary metabolite production in Cannabis sativa L. under salinity stress. A completely randomized design with three independent replicates (each replicate containing two pots) was employed. A factorial experiment was conducted with two factors: salinity at two levels (0 and 100 mM NaCl) and soil amendment at six levels (control, B. subtilis, P. putida, P-biochar, B. subtilis + P-biochar, and P. putida + P-biochar). Seeds were inoculated with PSB and P-biochar was mixed into soil at 2% (w/w). Salinity decreased plant biomass, chlorophyll (Chl), relative water content (RWC), essential oil (EO) yield, and cannabinoids, while increasing proline and malondialdehyde (MDA) compared to the control (no salinity). In plants exposed to salinity stress, P-biochar in combination with B. subtilis and P. putida respectively increased shoot weight (25% and 24%), root weight (28% and 38%), Chl (33% and 29%), RWC (16% and 15%), proline (17% and 19%), EO yield (49% and 37%), cannabidiol (13% and 12%), and tetrahydrocannabinol (16% and 14%), but lowered MDA (23% and 21%) compared to salinity-only treatment. The results are limited to greenhouse conditions and require field validation. Nonetheless, this combined strategy is recommended to enhance plant resilience and optimize pharmacologically active compound production in saline environments.

ID: 42123526
Title: Species-Specific Effects of Humic Substances and Mycorrhiza on Antioxidant Defense and Metal Stress Tolerance in Cannabis sativa, Sorghum sudanense × bicolor, and Miscanthus × giganteus Under Field Conditions.
Abstract: Abiotic stresses, including heavy metal contamination, can severely impair plant growth and antioxidative defense. However, their adverse effects may be mitigated through sustainable strategies such as biostimulant application. This study investigated the effects of humic substances (HSs), alone or combined with mycorrhizal inoculation (M), on oxidative stress and antioxidative responses in Cannabis sativa, Sorghum sudanense × bicolor, and Miscanthus × giganteus grown under field conditions on metal-contaminated agricultural soil exceeding regulatory thresholds for Zn, Pb, and Cd. Plant growth, lipid peroxidation, stress-related metabolites (proline, sugars), antioxidative enzyme activities (catalase, CAT; ascorbate peroxidase, APX; guaiacol peroxidase, GOPX; glutathione reductase, GR, and superoxide dismutase, SOD), and leaf metal concentrations were analyzed. Biostimulants increased proline and sugars in Sorghum (by up to 55% and 80%, respectively), accompanied by reduced oxidative stress indicators and improved biomass (by 26%). In Cannabis, higher Cd and Pb concentrations following biostimulant treatments were associated with increased SOD, APX, and GR activities (by 33-267%), without affecting growth. In Miscanthus, increased lipid peroxidation (by 37-60%) occurred alongside enhanced GR and APX activities. These results indicate strong species-specific responses and absence of consistent synergistic effects of HSs and M, highlighting distinct physiological strategies of stress adaptation and antioxidative defense on metal-contaminated soils. Future research should address physiological and molecular mechanisms underlying these responses.

ID: 42123740
Title: Multielement Analysis of Selected Superfood Seeds and Grains Using ICP-OES: Sources of Essential and Toxic Elements.
Abstract: The term 'superfoods' refers to a rapidly expanding group of food products that have gained increasing global interest due to their high nutritional value and association with health-oriented dietary patterns. Many superfoods, particularly grains and seeds, are rich sources of essential minerals, plant protein, dietary fibre, and bioactive compounds, making them valuable components of gluten-free, vegetarian, and vegan diets. The aim of this study was to evaluate the elemental composition of selected superfood grains and seeds and to verify the reliability of manufacturers' declarations. The analyses confirmed that the investigated samples possess a rich macro- and trace elemental composition, with pronounced differences among product groups. Based on median concentrations, pumpkin and hemp seeds were characterized by generally high levels of Mg, K, P, Fe, Mn, and Zn, whereas chia seeds exhibited notably elevated Ca content. In contrast, quinoa and amaranth showed comparatively lower elemental concentrations. Most of the results obtained for the analysed products are within the permissible deviation from the value declared on the packaging, as specified in the relevant EU regulations. The presence of potentially toxic elements, including Al, Pb, and Cd, was also detected. Cadmium accumulation was of particular concern in flax seeds, where all samples exceeded the limit of quantification and approached permissible levels. Principal component analysis revealed clear clustering patterns, indicating similarities between amaranth and quinoa, as well as between hemp and pumpkin seeds, while chia and flax seeds formed distinct groups. These results highlight both the nutritional potential of superfoods and the necessity for independent verification of their elemental composition.

ID: 42140042
Title: Metal concentration in biological samples of shipyard welders: a scoping review.
Abstract: Welding fumes are an unavoidable by-product of welding processes and have been associated with various adverse health effects. In the shipbuilding industry, welders are potentially exposed to large amounts of welding fumes containing various metal species. For the assessment of health risks human biomonitoring (HBM) constitutes a valuable tool determining the actual internal exposure to the metal content. This review aims to provide an overview of the current HBM data on the internal metal burden of shipyard welders, including associations with 1) ambient monitoring (AM) data, 2) welding processes, and 3) an assessment of health risks for welders based on reported HBM results. PubMed and Web of Science were searched for HBM studies providing metal concentrations in biological samples from shipyard welders. Study characteristics, AM and HBM results, and welding processes were extracted. Twenty-two studies were included in this review. Overall, sixteen metals were quantified in biological samples, with manganese, nickel and chromium being the most frequently analysed. In welders, metal concentrations were 1.02 to 20.6 times higher than in controls for 81 % of the HBM data, with a statistically significant difference observed in 33 % of cases. Weak associations were found between metal levels and AM results or welding processes. The limitations of using occupational exposure limits for risk assessment were discussed. Prospective studies with a harmonised design are needed to elucidate causal relationships between welding fume exposure and systemic metal burden, and to facilitate an accurate assessment of the resulting health risks.

ID: 42213593
Title: The Determination of potentially toxic elements (Arsenic, Cadmium, Mercury, and Lead) in Hemp (Cannabis sativa L.) from using Inductively Coupled Plasma Optical Emission Spectroscopy (ICP OES).
Abstract: Hemp (Cannabis sativa L.) readily accumulates potentially toxic elements (PTEs) from soil. PTE exposure is linked to cancer, nephrotoxicity, and neurotoxicity. Non-intoxicating hemp products in New Jersey are not subject to mandatory PTE testing, posing a consumer safety risk. This study presents a single-laboratory validation of an ICP OES method for the determination of As, Cd, Pb, and Hg in hemp, evaluated against AOAC SMPR 2020.001 performance criteria. Ground hemp (0.125 g) was digested using HNO3/HCl/H2O2 (190 °C, 20 min) and diluted to 50 mL. Samples were analyzed on an Agilent 5800 ICP OES with a seven-point calibration (1-100 μg/L), Au/Sc internal standards, and KHP carbon for matrix matching. Spike recoveries for Cd (92.7%) and Pb (96.2%) met AOAC SMPR 2020.001 criteria (80-115%). Mercury recovery (47%) fell below acceptance limits due to matrix suppression and volatility losses. The As LOD (0.807 μg/g) exceeded sample concentrations in most specimens. LOQ values for all four elements exceeded the SMPR 2020.001 threshold of 10 µg/kg (0.01 µg/g). Calibration linearity was confirmed for all analytes (r ≥ 0.995). Partial validation was achieved: Cd and Pb demonstrated acceptable accuracy and repeatability, but LOQ criteria were not met for any analyte. ICP OES is not suitable for Hg or As at regulatory trace levels; ICP MS is recommended for these elements. This method offers a cost-effective screening tool for Cd and Pb in hemp. This study presents the first single-laboratory ICP OES validation for PTEs in hemp under AOAC SMPR 2020.001. Cd and Pb met accuracy and repeatability criteria; As and Hg did not meet sensitivity requirements. ICP MS is recommended for regulatory As and Hg testing in hemp.

ID: 42243928
Title: Nutritional, antinutritional, and heavy metal profiles of ethnopoultry botanicals in Central Uganda.
Abstract: In Central Uganda, smallholder farmers rely on indigenous ethnoveterinary botanicals as phytogenic feed additives (PFAs) for indigenous chickens (Gallus gallus domesticus). However, the balance between their nutritional benefits and toxicological risks remains poorly characterized. Following an ethnoveterinary survey in Najjembe sub-county where Capsicum frutescens (ranked 2nd ), Cannabis sativa (3rd ), and Nicotiana tabacum (4th) were prioritized by farmers, this study investigated their nutritional and safety profiles. Aloe vera (1st ) was excluded from analysis due to extensive prior documentation. Samples were analyzed for proximate, mineral, and antioxidant profiles using AOAC Official Methods. Antinutrients (tannins, oxalates, phytates) and heavy metals (Pb, Cd) were quantified using vanillin-HCl spectrophotometry and Atomic Absorption Spectrophotometry, respectively. Results showed significant nutritional variation among species (p < 0.05). C. sativa contained the highest crude protein (22.20 ± 1.1%) and was exceptionally rich in calcium and potassium. C. frutescens exhibited the highest caloric density (452.9 kcal/100 g) and antioxidant activity (IC50 = 11.78 mg/mL). Conversely, N. tabacum had the highest iron and magnesium but also the highest antinutrient concentrations. Critically, lead (Pb) and cadmium (Cd) levels in N. tabacum and C. sativa significantly exceeded FAO/WHO safety limits (Pb > 0.3 mg/kg), resulting in hazard indices (HI > 1.0), signaling potential health risks for chickens and consumers. While these plants offer high nutraceutical value, the heavy metal bioaccumulation in N. tabacum and C. sativa necessitates strict inclusion limits and processing to ensure food safety. C. frutescens is recommended as the most viable PFA for feed integration.

ID: 42354362
Title: Soy Whey Wastewater-Derived Sodium Alginate/Cellulose Composite Beads for Efficient Copper (II) Ion Adsorption: Performance and Mechanism.
Abstract: A sustainable alginate-based composite adsorbent was developed by valorizing soy whey wastewater for the efficient removal of copper (II) ions from aqueous solutions. Soy whey wastewater/sodium alginate/cellulose (SWWSAC) beads were fabricated via a controlled slow-release calcium ion cross-linking strategy. This strategy resulted in homogeneous gelation, effective encapsulation of wastewater-derived organics and the formation of a hierarchical mesoporous structure. Compared with pure sodium alginate (SA) and sodium alginate-cellulose (SAC) beads, the SWWSAC beads exhibited a significantly higher specific surface area (3.95 m2/g) and pore volume (0.021 cm3/g), thus having markedly enhanced copper (II) ion adsorption performance. Batch adsorption experiments demonstrate that the adsorption process was strongly dependent on solution pH, adsorbent dosage, contact time and initial metal concentration. Kinetic analysis indicates that the adsorption process followed a pseudo-second-order model, while equilibrium data were well described by the Langmuir isotherm, corresponding to monolayer chemisorption. Based on this isotherm, SWWSAC beads had a theoretical maximum adsorption capacity of 168.3 mg/g (25 °C), 190.8 mg/g (35 °C), and 204.4 mg/g (45 °C). Thermodynamic results reveal that the adsorption was spontaneous and endothermic. FTIR and XPS analyses confirm that copper (II) ion removal was governed by synergistic complexation involving carboxyl, hydroxyl, carbonyl, and protein-derived nitrogen-containing functional groups. Moreover, the SWWSAC beads had a copper (II) ion removal efficiency of (92.4 ± 0.4)% and retained 73.3% of their initial adsorption capacity after six regeneration cycles in actual electroplating wastewater treatment. In this process, the beads exhibited good anti-interference performance against coexisting cations and good structural stability. Therefore, this work demonstrates an effective and low-cost strategy for copper (II) ion removal while providing a value-added route for the sustainable utilization of soy whey wastewater.

ID: 42393418
Title: Design and functionalization of anthraquinone-modified graphene oxide as a high-performance recyclable adsorbent for selective removal of toxic heavy metals from aqueous systems.
Abstract: In this study, a novel anthraquinone-based ligand, 2-(4-aminostyryl)quinolin-8-ol (AQ), was synthesized and covalently functionalized onto graphene oxide (GO) and graphite (G) to yield GO-AQ and G-AQ nanocomposite adsorbents for efficient heavy metal removal. Structural elucidation using 1H-NMR spectroscopy confirmed the successful formation of the AQ ligand, evidenced by characteristic aromatic, amine, vinylic, and hydroxyl proton signals, which verify its high structural integrity and purity. FTIR analysis revealed distinct vibrational features corresponding to aromatic, C-N, and N-H functionalities, confirming a strong chemical interaction between AQ and GO through amide formation and epoxide ring-opening reactions, whereas interaction with graphite was predominantly physisorptive. XRD and FE-SEM analyses demonstrated structural modifications including partial restacking, increased disorder, and successful ligand incorporation on the GO surface, supported by EDX elemental mapping showing a uniform distribution of C, O, and N atoms. BET analysis confirmed mesoporous characteristics, with GO-AQ exhibiting a higher surface area and porosity compared to G-AQ. Adsorption studies for Pb2+ and Cd2+ ions demonstrated that GO-AQ exhibits superior uptake capacities of 140 mg/g and 130 mg/g, respectively. The process was accurately modeled by the Langmuir isotherm (R2 > 0.99), indicating a monolayer chemisorption mechanism. The adsorption performance was highly dependent on operational parameters, including pH, contact time, and initial metal concentration, with optimal removal achieved at pH 7 within 40 min. Furthermore, GO-AQ displayed excellent selectivity for multivalent heavy metal ions over lighter cations and retained over 98% of its adsorption efficiency after three consecutive regeneration cycles, confirming its reusability and structural integrity. Overall, the AQ-functionalized graphene oxide adsorbent presented herein represents a robust, high-performance, and sustainable material for the selective removal of toxic heavy metals from aqueous environments.