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.

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.

Rising human population has increased the utilization of available resources for food, clothes, medicine, and living space, thus menacing natural environment and mounting the gap between available resources, and the skills to meet human desires is necessary. Humans are satisfying their desires by depleting available natural resources. Therefore, multifunctional plants can contribute towards the livelihoods of people, to execute their life requirements without degrading natural resources. Thus, research on multipurpose industrial crops should be of high interest among scientists. Hemp, or industrial hemp, is gaining research interest because of its fastest growth and utilization in commercial products including textile, paper, medicine, food, animal feed, paint, biofuel, biodegradable plastic, and construction material. High biomass production and ability to grow under versatile conditions make hemp, a good candidate species for remediation of polluted soils also. Present review highlights the morphology, adaptability, nutritional constituents, textile use, and medicinal significance of industrial hemp. Moreover, its usage in environmental conservation, building material, and biofuel production has also been discussed.

Phytoextraction is currently investigated to effectively remediate soil contaminated by metals and provide highly competitive biomass for energy production. This research aimed to increase arsenic (As) removal from contaminated soil using industrial Cannabis sativa L., a suitable energy crop for biofuel production. Assisted phytoextraction experiments were conducted on a microcosm scale to explore the ability of two friendly treatments, sodium sulphate (SO₄) and exogenous cytokinin (CK), in increasing As phytoextraction efficiency. The results showed that the treatments significantly increased As phytoextraction. Cytokinin was the most effective agent for effectively increasing translocation and the amount of As in aerial parts of C. sativa. In fact, the concentration of As in the shoots of CK-treated plants increased by 172% and 44% compared to untreated and SO₄-treated plants, respectively. However, the increased As amount accumulated in C. sativa tissues due to the two treatments negatively affected plant growth. Arsenic toxicity caused a significant decrease in aerial C. sativa biomass treated with CK and SO₄ of about 32.7% and 29.8% compared to untreated plants, respectively. However, for our research purposes, biomass reduction has been counterbalanced by an increase in As phytoextraction, such as to consider C. sativa and CK an effective combination for the remediation of As-contaminated soils. Considering that C. sativa has the suitable characteristics to provide valuable resources for bioenergy production, our work can help improve the implementation of a sustainable management model for As contaminated areas, such as phytoremediation coupled with bioenergy generation.

Phytoremediation represents a natural method to remove contaminants from soil. The goal of this study was to investigate the potential of phosphate-assisted phytoremediation by two energy crops, Cannabis sativa L. and Brassica juncea L., for the sustainable remediation of heavily arsenic-contaminated industrial soil. The two species were investigated for uptake, translocation, and physiological effects of arsenic and phosphate in a microcosm test. Although C. sativa and B. juncea were symptomless when grown in arsenic-contaminated soil, an important reduction of biomass (50 and 25%, respectively) was observed as a stress marker. Phytotoxicity and cytotoxicity effects promoted by contaminated soils were investigated in both the species and a model plant for ecotoxicity studies, Vicia faba L., which is the most developed model to test genotoxicity effects in terms of chromosomal aberration and micronuclei presence. The higher amount of arsenic was found in C. sativa and B. juncea roots (on average 1473 and 778 mg kg⁻¹, respectively), but both species were able to uptake and translocate arsenic in leaves and stems, up to 47.0 and 189 mg kg⁻¹, respectively. Phosphate treatment had no effect on arsenic uptake in none of the crop, but significantly improved the plant performance. Biomass production resulted similar to that of B. juncea control plants. Antioxidant enzymatic activities and photosynthetic performance responded differently in the two crops. The present investigation provides new insight for a proficient selection of the most suitable crop species for sustainable phytomanagement of a highly polluted As-contaminated site by coupled phytoremediation-bioenergy approach.

Wastewater-based epidemiology (WBE) is an ever-increasing discipline that enables researchers to track near-real-time data concerning the recreational use of illicit drugs. Community illicit drug use was estimated in eleven Turkish cities, using eighteen wastewater treatment plants, representing the metropolitan cities and rural areas with different socio-demographic characteristics. In this study, 24-h composite influent wastewater samples were collected for 1 week per season between March 2019 and December 2019. Heroin, amphetamine, methamphetamine, ecstasy, cocaine, and marijuana were covered as illicit drugs in this study. Solid-phase extraction, LC-MS/MS separation, identification, and quantification were used as the analytical methods. Overall results indicate that both cocaine and MDMA usage increased in all cities on weekends. More specifically, it was observed that the average amount of cocaine use regarding 11 cities was 14.7 mg/1000 person/day, while figures for other substances are as follows: 9.5 for amphetamine, 34.5 for methamphetamine, 38.4 for MDMA, 42.2 for heroin, and lastly 5412 mg/1000p/day for marijuana. This study holds the position of being the most comprehensive one conducted, considering spatial and temporal datasets on illicit drug consumption obtained via WBE in Turkey.

Hemp (Cannabis sativa L.) seedlings were used to remove from water the fungicide metalaxyl-M and the endocrine disruptor (EDC) bisphenol A (BPA) at concentrations ranging from 2 to 100 μg mL⁻¹. In 7 days of exposure, despite the phytotoxicity of each compound that reduced elongation and biomass, the seedlings were able to remove between 67 and 94% of metalaxyl-M and between 86 and 95% of BPA. The amounts of metalaxyl-M and BPA extracted from plant dry biomass were in the range of 106–3861 μg g⁻¹ and 16–101 μg g⁻¹, respectively, and resulted positively correlated to both the dose of compound added (P ≤ 0.01) and the amount removed by the plants (P ≤ 0.01). Plant uptake and transformation were the main mechanisms involved in the removal of the compounds. In another set of experiments, hemp was used to remove a mixture of two pesticides, metalaxyl-M and metribuzin, and three EDCs, BPA, 17β-estradiol (E2), and 4-tert-octylphenol (OP), at concentrations of 10, 10, 10, 10, and 1 μg g⁻¹, respectively, from soil column not added and added with 2.5% (w/w) of a green compost (CM) or a wood biochar (BC). In 25 days, plants did not alter considerably the distribution of the compounds along the soil profile and were capable of removing, on average, 12, 11, 10, 9, and 14% of metalaxyl-M, metribuzin, BPA, E2, and OP, respectively. During growth, hemp transformed the compounds and accumulated part of them (except OP) mainly in the shoots. CM and, especially, BC significantly protected the plants from the toxicity of the compounds and enhanced the retention of the latter in soil, contrasting leaching. Thus, the single or synergistic use of hemp and amendments deserves attention being a very low-cost and eco-sustainable strategy to remediate water and soil.

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.

In this study, element content and health risk of the most popular herbs from Iran were evaluated. The samples of raw materials from 30 different herbs were purchased from the local markets of Iran. The concentration levels of some elements including macroelements (N, P, K, Ca, and Mg), micronutrients (Fe, Zn, Cu, Mn, and Na), and heavy metals (Cd, Ni, and Pb) of studied herbs were evaluated. The potential of health risks was calculated by Estimated Daily Intake (EDI), Target Hazard Quotient (THQ), and Hazard Index (HI). The analysis of variance (ANOVA) is used to test a hypothesis about differences between the mean values. The highest levels of Ca (20,000 ± 26.3 mg/kg), Mg (9600 ± 45.4 mg/kg), N (59,955 ± 11.55 mg/kg), P (6544 ± 20 mg/kg), and K (56,563.2 ± 18 mg/kg) were found in Zataria multiflora, Malva sylvestris, Acasia arbus, Cannabis sativa, and Amomum subulatum, respectively. In addition, the highest concentration levels of Fe (987 ± 75.27 mg/kg), Zn (1187.5 ± 10 mg/kg), Cu (64.2 ± 2 mg/kg), Mn (272.3 ± 66.62 mg/kg), and Na (2658.8 ± 20.3 mg/kg) were recorded in Bunium persicum, Peganum harmala, Papaver somniferum, Alpinia officinalis, and Cuminum cyminum, respectively. Acasia arbus, Anethum graveolens, and Malva sylvestris showed the highest concentration of Ni (6.07 ± 0.04 mg/kg), Cd (1.64 ± 0.16 mg/kg), and Pb (9.27 ± 0.25 mg/kg). Based on performed health risk assessment on the studied plants, EDI, THQ, and HI values of all of them were less than 1. This study indicated that there were several harmful elements in the herbs. The healthier plant species are those with the least concentration of Pb, Ni, and Cd, which include Vitex agnus-custus and Teucrium polium. On the other hand, the toxic plants with a higher concentration of Pb, Ni, and Cd included Malva sylvestris, Acasia arbus, and Anethum graveolens. In addition, evaluation of human risk assessment is an important factor for investigating the concentration of heavy metals harmful for human beings.

The safe disposal of post-methanated distillery sludge (PMDS) in the environment is challenging due to high concentrations of heavy metals along with other complex organic pollutants. The study has revealed that PMDS contained high amounts of Fe (2403), Zn (210), Mn (126), Cu (73.62), Cr (21.825), Pb (16.33) and Ni (13.425 mg kg⁻¹) along with melanoidins and other co-pollutants. The phytoextraction pattern in 15 potential native plants growing on sludge showed that the Blumea lacera, Parthenium hysterophorous, Setaria viridis, Chenopodium album, Cannabis sativa, Basella alba, Tricosanthes dioica, Amaranthus spinosus L., Achyranthes sp., Dhatura stramonium, Sacchrum munja and Croton bonplandianum were noted as root accumulator for Fe, Zn and Mn, while S. munja, P. hysterophorous, C. sativa, C. album, T. dioica, D. stramonium, B. lacera, B. alba, Kalanchoe pinnata and Achyranthes sp. were found as shoot accumulator for Fe. In addition, A. spinosus L. was found as shoot accumulator for Zn and Mn. Similarly, all plants found as leaf accumulator for Fe, Zn and Mn except A. spinosus L. and Ricinus communis. Further, the BCF of all tested plants were noted <1, while the TF showed >1. This revealed that metal bioavailability to plant is poor due to strong complexation of heavy metals with organic pollutants. This gives a strong evidence of hyperaccumulation for the tested metals from complex distillery waste. Furthermore, the TEM observations of root of P. hysterophorous, C. sativa, Solanum nigrum and R. communis showed formation of multi-nucleolus, multi-vacuoles and deposition of metal granules in cellular component of roots as a plant adaptation mechanism for phytoextraction of heavy metal-rich polluted site. Hence, these native plants may be used as a tool for in situ phytoremediation and eco-restoration of industrial waste-contaminated site.