Root Tips Of Vicia Faba Research Articles

Bio-Based Decontamination and Detoxification of Total Petroleum Hydrocarbon-Contaminated Dredged Sediments: Perspectives to Produce Constructed Technosols in the Frame of the Circular Economy

To accelerate the depletion of total petroleum hydrocarbons, a hydrocarburoclastic ascomycetes, Lambertella sp. MUT 5852, was bioaugmented to dredged sediments co-composting with a lignocellulosic matrix. After only 28 days of incubation, a complete depletion of the contamination was observed. The 16S rDNA metabarcoding of the bacterial community and a predictive functional metagenomic analysis were adopted to evaluate potential bacterial degrading and detoxifying functions. A combination of toxicological assays on two eukaryotic models, the root tips of Vicia faba and the human intestinal epithelial Caco-2 cells, was adopted to assess the robustness of the process not only for the decontamination but also for the detoxification of the dredged sediments. Bacterial taxa, such as Kocuria and Sphingobacterium sps., resulted to be involved in both the decontamination and detoxification of the co-composting dredged sediments by potential activation of diverse oxidative processes. At the same time, the Kocuria sp. showed plant growth-promoting activity by the potential expression of the 1-aminocyclopropane-1-carboxylate deaminase activity, providing functional traits of interest for a technosol in terms of sustaining primary producer growth and development.

Micronucleus Induction in Vicia faba Root Tips by Crude Oil-Polluted Soil from Ecuadorian Amazon

In the past four decades, the Amazon rainforest has emerged as a crucial zone for crude oil extraction in the South American region. In the Ecuadorian Amazon rainforest, hydrocarbon blocks (called “bloques”) cover vast zones, including agricultural and livestock farms, protected natural regions and the territories of uncontacted indigenous tribes. This study proposes a micronuclei assay on Vicia faba following a 24 h exposure to various soil samples collected from Bloque 57 in Ecuador. Sampling was conducted between the Dayuma and Aguarico zones, approximately 30 km from Nueva Loja city. The research aimed to assess the impact of different soil samples, particularly those from areas affected by crude oil spills, to induce micronuclei and mitotic index changes in V. faba roots. Results: The soil pollution caused by crude oil is not the sole factor contributing to cytotoxicity and genotoxicity in V. faba. Most samples from areas polluted by crude oil outside the small-scale farm showed no significant difference in micronuclei rate compared to negative control and Amazon unpolluted soil. Conversely, samples from the small-scale farm displayed a statistically significant genotoxic effect. Furthermore, samples collected from open-air wastewater pools demonstrated higher levels of cytotoxicity compared to the controls and those from small-scale farms. The mitotic index was lower in seedlings exposed to wastewater in open-air pools, especially for the 20 cm deep samples. This phenomenon could be linked to bitumen-like substances and oils floating on the surface, attaching to the small roots and causing suffocation.

O2 plasma-modified carbon nanotube for sulfamethoxazole degradation via peroxymonosulfate activation: Synergism of radical and non-radical pathways boosting water decontamination and detoxification

Sulfamethoxazole (SMX), a widely used antibiotic, has triggered increasing attention due to its extensive detection in wastewater effluent, causing serious ecological threats. Herein, a carbon-based heterogeneous catalyst was developed by the O2 plasma-etching process, regulating oxygen-containing functional groups (OFGs) and defects of carbon nanotubes (O-CNT) to activate peroxymonosulfate (PMS) for highly efficient SMX abatement. Through adjusting the etching time, the desired active sites (i.e., C=O and defects) could be rationally created. Experiments collectively suggested that the degradation of SMX was owing to the contribution of synergism by radical (•OH (17.3%) and SO4•– (39.3%)) and non-radical pathways (1O2, 43.4%), which originated from PMS catalyzed by C=O and defects. In addition, the possible degradation products and transformation pathways of SMX in the system were inferred by combining the Fukui function calculations and the LC-MS/MS analysis. And the possible degradation pathway was effective in reducing the environmental toxicity of SMX, as evidenced by the T.E.S.T. software and the micronucleus experiment on Vicia faba root tip. Also, the catalytic system exhibited excellent performance for different antibiotics removal, such as amoxicillin (AMX), carbamazepine (CBZ) and isopropylphenazone (PRP). This study is expected to provide an alternative strategy for antibiotics removal in water decontamination and detoxification.

Cytotoxicity and genotoxicity evaluation of chloroform using Vicia faba roots.

Chloroform is a widely used industrial chemical that can also pollute the environment. The aims of this study were to examine the potential cytotoxicity and genotoxicity of chloroform on plant cells, using the Vicia faba bioassay. Chloroform was evaluated at concentrations of 0.1, 0.5, 1, 2, and 5mg·L-1. The following parameters were analyzed: the mitotic index (MI), micronucleus (MN) frequency, chromosomal aberration (CA) frequency, and malondialdehyde (MDA) content. The results showed that exposure to increasing concentrations of chloroform caused a decrease in MI and an increase in the frequency of MN in Vicia faba root tip cells, relative to their controls. Moreover, various types of CA, including C-mitosis, fragments, bridges, laggard chromosomes, and multipolar mitosis, were observed in the treated cells. The frequency of MN was positively correlated with the frequency of CA in exposure to 0.1-1mg·L-1 chloroform. Furthermore, chloroform exposure induced membrane lipid peroxidation damage in the Vicia faba radicle, and a linear correlation was observed between the MDA content and the frequency of MN or CA. These findings indicated that chloroform exposure can result in oxidative stress, cytotoxicity, and genotoxicity in plant cells.

Toxic effects of chemical plant residues on soil

Soil samples were collected from 6 different areas of the abandoned pesticide factory site, numbered p1, p2, p3, p4, p5, and p6, respectively. Based on the acute toxicity of Luminescent bacteria and Flea and the genotoxicity of Vicia faba root tip micronucleus, the ecotoxicological diagnosis of soil extracts from 6 samples was carried out. The results showed that the relative luminosity of the 6 kinds of extracts to luminescent bacteria were 50.7%, 56.3%, 43.7%, 53.0%, 49.6% and 67.6%, respectively. The 48-hour acute toxicity EC50 of the large flea was 6.15%, 8.65%, 0.57%, 2.52%, 0.33% and 14.94%, respectively. The results of the photobacterial experiment were basically consistent with the acute toxicity results of Flea daphnia, and the results showed that the soil pollution of the pesticide factory site was relatively serious.

Municipal solid waste landfill leachate induced cytotoxicity in root tips of Vicia faba: Environmental Risk posed by non-engineered landfill

Landfills are considered the main option for dumping of municipal solid waste (MSW) all over the world, but these landfills are mostly non-engineered. The decomposition of solid waste in the landfill and rainwater penetration into the decomposing waste produces leachate that contains dissolved organic and inorganic compounds, heavy metals, suspended particles, and hazardous substances. Leachate migration in the environment may pose serious health risks to organisms exposed. Hence, the present study explored the cytotoxic potential of landfill leachate collected in different seasons from the Okhla landfill site, Delhi, India. Cytotoxicity of leachate samples was evaluatedby cell apoptosis and ultrastructural observation based on Transmission Electron Microscopy (TEM) of the cells of root tips of vicia faba seedlings treated with the leachates collected in summer, winter and monsoon in a time and dose dependent manner. Leachate collected in all the three seasons induced apoptosis in cells of root tips of vicia faba that increased in a time and dose dependent manner when compared to control. The apoptosis was highest in the samples treated with leachate collected in the summer season, followed by winter and monsoon. It was further confirmed with TEM images that there was induction of apoptotic-like morphological changes in the root cells treated with landfill leachate when compared with the control. The present study indicates that municipal solid waste leachate is very toxic and it should be treated before disposing it to the environment.

Oxidation of pyrazolone pharmaceuticals by peracetic acid: Kinetics, mechanism and genetic toxicity variations

Peracetic acid (PAA) oxidation is an emerging technology in water disinfection and purification. This study evaluated the oxidation of three pyrazolone pharmaceuticals (i.e., Aminopyrine (AMP), Antipyrine (ANT), and Isopropylphenazone (PRP) by PAA. Experimental results showed that PAA exhibited structure selectivity to the above three pharmaceuticals and oxidized AMP with the highest reactivity. The degradation kinetics of AMP was investigated by calculating the apparent second-order rate constants (kapp) under different initial pH. Through kinetic simulation, the second-order rate constants of elementary reactions between AMP (i.e., neutral (AMP0) and protonated (AMP+) species) with PAA (i.e., neutral (PAA0) and anionic (PAA−) species) were obtained to be 0.34 ± 0.077 M−1 s−1(k”AMP+, PAA0), 0.89 ± 0.091 M−1 s−1(k”AMP0, PAA-) and 5.94 ± 0.142 M−1 s−1(k”AMP0, PAA0), respectively. The PAA could oxidize AMP via electrophilic attack, and the degradation site of AMP was confirmed to be the central nitrogen of –N(CH3)2 with the highest relative electrophilicity (sk-/sk+, 48.8614) by Density Functional Theory (DFT) calculation. The intermediates/products of AMP degradation were identified by high-performance liquid chromatography-mass spectrometry (LC-MS/MS), and the transformation pathways of AMP during PAA oxidation were inferred to be hydroxylation, demethylation, and CC cleavage. The genetic toxicity of AMP contaminated water could be reduced after PAA oxidation, which was evaluated by the micronucleus test of Vicia faba root tips.

Electrochemical activation of peroxymonosulfate (PMS) by carbon cloth anode for sulfamethoxazole degradation

Electrochemical activation of peroxymonosulfate (PMS) at carbon cloth anode (E (Carbon cloth Anode)/PMS system) was investigated for sulfamethoxazole (SMX) degradation. The results indicated that PMS could be activated at carbon cloth anode during electrolysis, resulting in the improvement of SMX degradation. The degradation efficiency of SMX was facilitated with the higher PMS concentration and current density, respectively. The degradation rate constant of SMX increased with the rising pH from 3.6 to 6.0, and reached the highest value at pH 6.0, and then decreased with further increasing pH to 8.0. The presence of chloride ion (Cl−, 5–100 mM) significantly enhanced SMX degradation, while addition of humic acid (HA, 1–5 mgC L−1) inhibited SMX degradation. Addition of carbonate (HCO3−, 5–20 mM) had a negligible impact on SMX degradation. Small amounts of phosphate (PO43−, 0–5 mM) could promote degradation, while a large amount of PO43− (10–20 mM) inhibited the degradation. Moreover, the quenching experiments demonstrated that sulfate radical (SO4·−), hydroxyl radical (·OH) and singlet oxygen (1O2) contributed to SMX degradation in E (Carbon cloth Anode)/PMS system. The degradation intermediates of SMX were identified by LC-MS/MS and the degradation pathways were deduced to be hydroxylation, the cleavage of S–N bond, and oxidation of aniline group. Moreover, the micronucleus test of Vicia faba root tips indicated that the E (Carbon Cloth Anode)/PMS system could reduce the genetic toxicity of SMX contaminated water to some extent.

Preliminary assessment of genotoxic effects induced by radiation from EAST using Vicia faba micronucleus assay

During long-pulse deuterium plasma operations in the Experimental Advanced Superconducting Tokamak (EAST), a mixed radiation field is generated, which is mainly composed of fusion neutrons, gamma rays, and x-rays. More accurate and effective dose monitoring methods have been developed and established to determine the ionizing radiation intensity both for the stable operation of the device and for the radiation safety of personnel. As far as we know, there are few reports about the biological effects of radiation induced by fusion neutrons and γ radiation, which are of vital importance for the assessment of radiation hazards presented by fusion devices, such as EAST, to human beings and the environment. In this study, three positions in the EAST hall were selected to detect genotoxic effects induced by nuclear fusion radiation using a Vicia faba micronucleus (MN) test for the first time. The doses of neutrons and gamma rays at these places were measured by thermoluminescence dosimeters four times between June 2019 and May 2020. The radiation doses decreased as the distances from the EAST device shell gradually increased from S1 to S3. The radiation in the EAST hall resulted in a significant induction of MN in the Vicia faba root tip cells compared to a negative control, which was different from the MN frequency induced by fission neutrons, γ-rays and other kinds of radiation in previous studies. These results indicate the existence of potential genotoxic effects induced by radiation from EAST which is different from other radiation and suggest that personnel should not be permitted to enter the experimental hall during the discharge process, and that radiation protection measures should be taken during necessary maintenance to avoid radiation damage. These newly acquired results will certainly increase our knowledge about the biological effects induced by radiation from nuclear fusion and provide good data support for developing more effective environmental and personnel fusion radiation protection.

Microbiological quality and genotoxicity of domestic water sources: A combined approach using Micro Biological Survey method and mutagenesis assay (micronucleus test) in root tips of Vicia faba in the West region of Cameroon.

At least 2.1 billion people around the world use contaminated drinking water, causing 485,000 diarrheal deaths each year, mostly among children under 5 years old. A study conducted 10 years ago in Bafoussam (West Cameroon) recorded concentrations of bacteria among surface and groundwater. High levels of bicarbonates, phosphates, chlorides and suspended matters were also found. The aim of this study was to assess the microbiological and chemical qualities of domestic water sources in 5 localities of the West region of Cameroon. Water samples from 22 water sources (wells, springs, water drilling and river) were aseptically collected in plastic bottles and transferred in 50 ml sterile tubes. For chlorinated water sources, 1 ml of Thiosulfate was added to the water sample; immediately placed in an ice box and transported to the laboratory for analysis. Water temperature and pH were measured on site. The microbiological quality of water was determined by testing Total Coliforms (TC) using the Micro Biological Survey method. 1 ml of each water sample was inoculated in the MBS vial initially rehydrated with 10 ml of sterile distilled water. The initial color of the vials is red. Color changes were monitored at three different time intervals (12h, 19h and 24h), corresponding to three levels of contamination. The chemical quality of water was assessed using micronucleus (MN) test in selected Vicia faba seeds secondary root tips permanently mounted in Dibutylphthalate Polystyrene Xylene mountant for histology after 72 hours of direct exposition in water samples and in dark. The mitotic indices and MN frequencies were evaluated in 10 root tips per site analysing 5000 cells per tip. Statistical analyses were done using Stata IC/15.0 software. The Student t-test was used for mean comparison and the significance level was set at 1%. The majority of samples were collected from wells (63.6%). The mean water pH ranged from 5.5 to 8.3 and the temperature varied from 23 to 26°C. A very high concentration of TC [>103 CFU/ml] was found in 8 (36.4%) samples. 10 (45.5%) and 2 (9.1%) samples turned yellow at 19 and 24 hours respectively after incubation corresponding to TC concentration of [10<x<103 CFU/ml] and [1<x< 10 CFU/ml]. The MN frequency was higher (P ≤ 0.01) compared to the negative control in 9 (40.9%) water samples indicating significant genotoxic effects of these water sources. This study highlighted the poor quality of domestic water sources in West region of Cameroon and the need to conduct regular monitoring of drinking water sources. Community capacity building on water treatment methods, including good wastes management should be implemented to help improve water quality.

Genotoxicity response of Vicia faba seedlings to cadmium in soils as characterized by direct soil exposure and micronucleus test.

To overcome the drawbacks of the Vicia faba root tip micronucleus test in soil using the solution extract method, we conducted a potting experiment by direct soil exposure. Cadmium was spiked into 3 typical soils (brown soil, red soil, and black soil) to simulate environmental concentrations (0.625, 1.25, 2.5, 5, and 10 mg kg-1). Multiple Vicia faba tissues (primary root tips, secondary root tips, and leaf tips) were sampled, and mitotic index (MI), chromosome aberration frequency (CA), and micronucleus frequency (MN) were used as endpoints after a seedling period of 5 days. The results showed a response between Cd concentrations and multiple sampling tissues of Vicia faba, and the secondary root tips responded to Cd stress the most, followed by primary root tips and leaf tips. Soil physicochemical properties (e.g., pH, total phosphorus, total organic carbon, etc.) influenced the genotoxicity of Cd, and pH was the dominant factor, which resulted in the genetic toxicity response of Cd in soils in the order: red soil > brown soil > black soil. The lowest observable effect concentration (LOEC) of Cd was 1.25 mg kg-1 for both brown soil and red soil and 2.5 mg kg-1 for black soil. In view of this, we suggested that soil properties should be considered in evaluating genotoxicity risk of Cd in soil, especially with soil pH range, and the secondary root tips should be taken as suitable test tissues in the MN test due to its more sensible response feature to Cd stress in soil.

Degradation behaviors of Isopropylphenazone and Aminopyrine and their genetic toxicity variations during UV/chloramine treatment

Combination of ultraviolet and chloramine (i.e., UV/chloramine) treatment has been attracting increasingly attention in recent years due to its high efficiency in removing trace organic contaminants. This study investigated the degradation behaviors of two pyrazolone pharmaceuticals (i.e., Isopropyl phenazone (PRP) and Aminopyrine (AMP)) and their genetic toxicity variations during UV/chloramine treatment. The results showed that chloramine could hardly degrade PRP and AMP, while UV/chloramine greatly increased the observed first-order rate constant (kobs) of PRP and AMP degradation. The quenching and probe experiments illustrated that the reactive chlorine species (RCS) contributed dominantly to PRP removal, and hydroxyl radical (HO•) was the major contributor to the degradation of AMP, while the reactive amine radicals (RNS) could hardly degrade them. The overall degradation rates of PRP and AMP decreased as pH increased from 6.5 to 10. The kobs of PRP and AMP increased along with NH2Cl dosage increasing and reached a plateau at higher concentrations (0.2–0.5 mM). The present background carbonate (HCO3−, 1–10 mM), chloride (Cl−, 1–10 mM) and natural organic matter (NOM, 5-10 mg-C L−1) exhibited inhibition impacts on PRP and AMP degradation. In addition, the intermediates/products of PRP and AMP were identified and their general degradation pathways were proposed to be hydroxylation, deacetylation, and dephenylization. Specifically, Cl-substitution was inferred during PRP degradation, while demethylation in tertiary amine group was only observed in AMP degradation. These mechanisms including the main reactive sites of PRP and AMP were further confirmed by the frontier orbitals calculation. Moreover, the results of the genetic toxicity according to the micronucleus test of Viciafaba root tip indicated that UV/chloramine treatment could partially reduce the genetic toxicity of PRP and AMP.

Immobilization of heavy metals in vegetable-growing soils using nano zero-valent iron modified attapulgite clay

Nowadays, the problem of heavy metal pollution in vegetables is received wide attention. In this work, attapulgite clay (ATTP), as a cheap and readily available inorganic mineral material, was modified with nano zero-valent iron (nFe0@ATTP) for heavy metal immobilization in soil. Batch experiments were employed to evaluate the optimal remediation performance by ATTP before and after modified with nFe0 through planting Pakchoi (Brassica chinesis L.) in Cd, Cr, and Pb contaminated soil from Changsha. The results showed that amendments can all increase the pH value of soils, and notably decrease the concentration of extractable Cd, Cr, and Pb in soil. The germination rate and root length of Pakchoi were promoted, and the activities of peroxidase (POD), catalase (CAT), and malondialdehyde (MDA) contents were notably reduced besides superoxide dismutase (SOD) activity after treatments with ATTP and nFe0@ATTP. Vicia faba-micronucleus test indicated that the application of amendments reduced the toxicity of heavy metals on the genetic material of Vicia faba root tip cells. The nFe0@ATTP were found to well convert Cd, Cr, and Pb into less bioavailable state in soil, thus blocking heavy metal uptake by plants. This material could be a promising amendment for heavy metals contaminated soil.

Ecotoxicity and genotoxicity of polystyrene microplastics on higher plant Vicia faba

Nano- and microplastics have been widely spread in environmental matrices, especially in marine and terrestrial systems. In this study, higher plant Vicia faba root tips were exposed to 5 μm and 100 nm with 10, 50 and 100 mg/L polystyrene fluorescent microplastics (PS-MPs) for 48 h. Root length, weight, oxidative stress and genotoxicity of V. faba were assessed to investigate toxic effects of PS-MPs. The results showed that the biomass and catalase (CAT) enzymes activity of V. faba roots decreased under 5 μm PS-MPs whereas superoxide dismutase (SOD) and peroxidase (POD) enzymes activity significantly increased. Under the 100 nm PS-MPs exposure a significant decrease of growth was observed only at the highest concentration (100 mg/L). However, micronucleus (MN) test and antioxidative enzymes activities showed that 100 nm PS-MPs induce higher genotoxic and oxidative damage to V. faba than 5 μm PS-MPs. Furthermore, the laser confocal scanning microscopy (LCSM) demonstrated that 100 nm PS-MPs can accumulate in V. faba root and most probably block cell connections or cell wall pores for transport of nutrients. These findings provide a new insight into the toxic effects of microplastics on V. faba, and further apply to the ecological risk assessment of microplastics on higher plants.

Fuzzy Evaluation of Water Quality Based on Micronucleus Technology of Vicia faba Root Tip

By establishing a fuzzy mathematical evaluation model based on physical and chemical indicators, this paper investigates the genetic toxic pollution of Chaohu Lake in 2016 through the micronucleus technology of the Vicia faba root tip and evaluates the water quality of Chaohu Lake. The results show that, in recent years, the overall water quality of the lakes around Chaohu has improved slightly, but the pollution levels of some areas (such as Nan Fei He and Shi Wu Li He) are still serious. The results can also provide a more reliable theoretical basis for the planning and management of environment protection.

Photoelectrocatalytic degradation of microcystin-LR using a dimensionally stable anode and the assessment of detoxification

Microcystins (MCs) pose a great threat to human health due to their toxicity. In this study, photoelectrocatalysis was applied as an effective technology to degrade MCs. The effects of different dimensionally stable anodes and cathodes were evaluated. Detoxification effects were investigated using a luminescence inhibition assay, a micronucleus assay of Vicia faba root tips and a single cell gel electrophoresis assay. The results show that RuO2-TiO2/Ti and stainless steel were the best among the six anodes and four cathodes tested for MCLR degradation. Compared to photodegradation, photocatalysis and electrocatalysis, photoelectrocatalysis obtained the highest efficiency on MCLR degradation, nearly 100% at 254 nm and 5.0 mA/cm2. The degradation kinetics agreed with the Langmuir-Hinshelwood kinetic model. When NaCl was used as an electrolyte, the degradation efficiency of MCLR reached 100% even under 0.002 mol/L, which was much better than that of Na2SO4, Na2HPO4 and NaNO3. The toxicity assays showed that although MCLR was completely degraded, acute toxicity still occurred in the solution at relative luminosities from 0 to 9.37%. However, the micronucleus efficiency and DNA damage of cells returned to normal levels at the end of the reaction. This indicates that genotoxicity and cytotoxicity were eliminated with the degradation of MCLR.

Phytotoxicity and phytogenotoxicity of soils in the area of liquidated pesticide-burial ground

Abstract Phytotoxicity and phytogenotoxicity of soils in the area of liquidated pesticide-burial ground. First efforts to reduce the environmental risks caused by existing pesticide burial grounds were undertaken in Poland at the beginning of the 1990s. Work on their liquidation was accelerated after the adoption of the fi rst National Waste Management Plan 2006 and National Waste Management Plan 2010. In 2011 The Supreme Audit Offi ce carried out an assessment of the realisation of the plans, which revealed the negligence in monitoring of the areas of liquidated pesticide burial grounds, whilst even after the land reclamation process, the remaining contamination could still pose environmental risk. In such areas, to evaluate the impact of the mixture of potentially present toxic and genotoxic substances, higher plant bioassays are very useful. On the example of liquidated pesticide burial ground in Grójec we concluded, that after several years from the liquidation and land reclamation processes, environmental impact of this type of facility could still be perceptible. Phytogenotoxicity of soil samples, collected from the liquidated burial site and the immediate vicinity, was detected with Vicia faba Root Tip Assay.

Influence of isolated bacterial strains on the in situ biodegradation of endosulfan and the reduction of endosulfan- contaminated soil toxicity

The recently discovered endosulfan-degrading bacterial strains Pusillimonas sp. JW2 and Bordetella petrii NS were isolated from endosulfan-polluted water and soil environments. The optimal conditions for the growth and biodegradation activity of the strains JW2 and NS were studied in detail. In addition, the ability of the strains JW2 and NS to biodegrade endosulfan in soils during in situ bioremediation experiments was investigated. At a concentration of 2 mg of endosulfan per kilogram of soil, both JW2 and NS had positive effects on the degradation of endosulfan; JW2 degraded 100% and 91.5% of α- and β-endosulfan, respectively, and NS degraded 95.1% and 90.3% of α- and β-endosulfan, respectively. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) of soil samples showed the successful colonization of JW2 and NS, and the toxicity of the soil decreased, as determined by single-cell gel electrophoresis (SCGE) assays of Eiseniafetida and micronucleus (MN) assays of Viciafaba root tip cells. Furthermore, the metabolic products of the bacterially degraded endosulfan from the in situ experiments were identified as endosulfan ether and lactone. This study provided potentially foundational backgrounds information for the remediation of endosulfan-contaminated soil.

Degradation behaviors and genetic toxicity variations of pyrazolone pharmaceuticals during chlorine dioxide disinfection process

Pyrazolone pharmaceuticals such as isopropylphenazone (PRP) and aminopyrine (AMP) were commonly used as antipyretic analgesics, and their frequently detection in aquatic environment has become a major concern in recent years. Chlorine dioxide (ClO2) disinfection process has been proved to be a feasible way to degrade antipyrine (ANT), which is the first synthetic pyrazolone pharmaceutical. In this work, the reaction kinetics, degradation pathways and genetic toxicity of PRP and AMP during ClO2 disinfection process were investigated. Experimental results demonstrated that the reaction of both PRP and AMP with ClO2 followed second-order kinetics, the second-order rate constants were calculated to be kapp(PRP) = 11.0 M−1 s−1 and kapp(AMP) = 1.30 × 105 M−1 s−1 at neutral pH. Slightly alkaline environment (pH = 9) was in favor of the reaction. CC double bond and CN bond on pyrazolone ring were main active groups under ClO2 electrophilic attack. The degradation pathways of pyrazolone pharmaceuticals could be concluded as CC cleavage, ring-opening reaction and de-carbonyl reaction. Pyrazolone contaminated water exhibited genetic toxicity according to micronucleus test of Viciafaba root tip, however, the toxicity could be reduced through ClO2 disinfection process.

Genetic Toxicity of Solidago canadensis

Solidago decurrens is a plant of Asteraceae, which is mainly produced in southern China. It is widely used cut flower material. It is known as the malignant weed Solidago canadensis (Solidago canadensis) with the genus Flora, so its application of ecological security has been a big debate. In this paper, the allelopathic effect of the water extract of Solidago macrophylla was studied by using the micronucleus technique of Vicia faba root tip as the experimental material. The aim of this study was to analyze the genetic toxicity of Solidago canadensis. The results showed that: (1) The water extract of Solidago canadensis could decrease the mitotic index and interfere with the normal process of mitosis, where the decreased rate was positively correlated with the concentration of water extract and treatment time. (2) The effects of water extract on the root tip of Vicia faba were significant increases with time and concentration effect (3) Achilla glauca extract could make the chromosome bridge, chromosome fragment, chromosome lag in the root tip cells of Vicia faba and increase in micronucleus rate. The results showed that the water extract of Solidago canadensis had different degree of inhibition and damage to silkworm root tip cells; it also had some genetic toxicity and rapid diffusion ability.