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Reprotoxicity of glyphosate-based formulation in Caenorhabditis elegans is not due to the active ingredient only
2019
Jacques, Mauricio Tavares | Bornhorst, Julia | Soares, Marcell Valandro | Schwerdtle, Tanja | Garcia, Solange | Ávila, Daiana Silva
Pesticides guarantee us high productivity in agriculture, but the long-term costs have proved too high. Acute and chronic intoxication of humans and animals, contamination of soil, water and food are the consequences of the current demand and sales of these products. In addition, pesticides such as glyphosate are sold in commercial formulations which have inert ingredients, substances with unknown composition and proportion. Facing this scenario, toxicological studies that investigate the interaction between the active principle and the inert ingredients are necessary. The following work proposed comparative toxicology studies between glyphosate and its commercial formulation using the alternative model Caenorhabditis elegans. Worms were exposed to different concentrations of the active ingredient (glyphosate in monoisopropylamine salt) and its commercial formulation. Reproductive capacity was evaluated through brood size, morphological analysis of oocytes and through the MD701 strain (bcIs39), which allows the visualization of germ cells in apoptosis. In addition, the metal composition in the commercial formulation was analyzed by ICP-MS. Only the commercial formulation of glyphosate showed significant negative effects on brood size, body length, oocyte size, and the number of apoptotic cells. Metal analysis showed the presence of Hg, Fe, Mn, Cu, Zn, As, Cd and Pb in the commercial formulation, which did not cause reprotoxicity at the concentrations found. However, metals can bioaccumulate in soil and water and cause environmental impacts. Finally, we demonstrated that the addition of inert ingredients increased the toxic profile of the active ingredient glyphosate in C. elegans, which reinforces the need of components description in the product labels.
Show more [+] Less [-]A multi-year study of VOC emissions at a chemical waste disposal facility using mobile APCI-MS and LPCI-MS instruments
2018
Healy, Robert M. | Chen, Qingfeng | Bennett, Julie | Karellas, Nicholas S.
Real-time analysis of volatile organic compounds (VOCs) in air is useful both for source identification and emissions compliance applications. In this work, two complementary triple quadrupole mass spectrometers, fitted with an atmospheric pressure chemical ionization (APCI) and a low pressure chemical ionization (LPCI) source, respectively, were deployed simultaneously to investigate emissions of VOCs associated with an Ontario-based chemical waste disposal facility. Mobile measurements performed upwind and downwind of the facility enabled selection of the best locations for stationary sampling. Seven separate field studies were undertaken between 2000 and 2016 to assess how emissions of VOCs have changed at the site as a function of time. Up to twenty-nine VOCs were successfully identified and quantified using MS/MS in each study. Simultaneous deployment of the two mass spectrometers enabled the detection of polar VOCs including alcohols, esters, amines and ketones as well as non-polar aromatic VOCs including benzene and naphthalene in real time. Concentrations of VOCs were found to decrease significantly in the vicinity of the facility over the sixteen year period, in particular since 2007. Concentration values for each year are compared with odour thresholds and provincial guidelines and implications of future expansion of on-site solid waste landfill volumes are also discussed.
Show more [+] Less [-]Sub-lethal effects of a glyphosate-based commercial formulation and adjuvants on juvenile oysters (Crassostrea gigas) exposed for 35days
2017
Séguin, Alexis | Mottier, Antoine | Perron, Carole | Lebel, Jean Marc | Serpentini, Antoine | Costil, Katherine
Glyphosate-based herbicides include active matter and adjuvants (e.g. polyethoxylated tallow amines, POEAs). In addition to a previous investigation on the effect of glyphosate on oysters, the aim of the present study was to investigate the effects of sub-chronic exposures (35days) to three concentrations (0.1, 1 and 100μgL−1) of Roundup Express® (REX) and POEAs on oysters belonging to the same age group. Low mortality rates were calculated, and only few significant differences (i.e. shell length) between exposure conditions were observed at a given date. However, when comparing the biomarker's temporal variations, some different patterns (e.g. condition index, reproduction, parameters of oxidative stress) were observed depending on the molecules and concentrations. These results suggest that a longer exposure to an environmental concentration (0.1μgL−1) of REX and POEAs could induce harmful effects on oysters.
Show more [+] Less [-]The use of surface-enhanced Raman scattering (SERS) for detection of PAHs in the Gulf of Gdańsk (Baltic Sea)
2012
(Heinz-Detlef),
A field operable surface enhanced Raman scattering (SERS) sensor system was applied for the first time under real conditions for the detection of polycyclic aromatic hydrocarbons (PAHs) as markers for petroleum hydrocarbons in the Gulf of Gdańsk (Baltic Sea). At six stations, seawater samples were taken, and the sensor system was applied in situ simultaneously. These measurements were compared to the results of conventional GC/MS laboratory analysis of the PAH concentrations in the seawater samples. For a PAH concentration above 150ng(12PAH)l⁻¹, there was agreement between the SERS sensor and the GC/MS determinations. A standard addition experiment yielded a PAH concentration of 900ngl⁻¹ at the Gdańsk Harbor, which was of the same order as the GC/MS determinations of 12PAHs (200ng(12PAH)l⁻¹). The high SERS detection limit for seawater samples is explained by the competition for PAHs between the sensor membrane and particulate matter surfaces. Thus, the SERS sensor can be applied, e.g., as a non-quantitative alarm sensor for relatively high PAH concentrations in heavily polluted waters. The spectral unmixing procedure applied for Gdańsk Harbor water confirmed the presence of phenanthrene at the highest concentration ([Phe]=140ngl⁻¹) and of Chr (2.7ngl⁻¹), but it did not detect the other PAHs present in the Gdańsk Harbor water, as determined by GC/MS. When compared to the past literature and databases, the SERS spectra indicated the presence of a mixture of molecules consisting of carotenoids, n-alkanes, amines or fatty acids, and benzimidazoles at the coastal station ZN2. The spectra in the offshore direction indicated carboxylic acids. Interpretation of the farthest offshore in situ SERS measurements is difficult, principally due to the limited availability of reference spectra. The detection of the lower PAH concentrations commonly found in Baltic coastal water needs further research and development to obtain better sensitivity of the SERS sensor. However, the high analytical specificity of the SERS sensor also allows the detection of other chemical species that require the development of a SERS/Raman library for specific in situ spectral interpretation.
Show more [+] Less [-]Biochemical response of Norway spruce (Picea abies (L.) Karst.) towards 14-month exposure to ozone and acid mist: effects of amino acid, glutathione and polyamine titers
1990
Dohmen, G.P. | Koppers, A. | Langebartels, C. (Institut fur Toxikologie, GSF Munchen, 8042 Neuherberg (Germany))
Synthesis and Metal-Ion Uptake Properties of a New Dithiocarbamate-Base Resin
2017
Sarikahya, Hasan | Scalzo, Rachel D. | Alawaed, Abdulkhaliq | Niri, Vadoud | Damkaci, Fehmi
A new dithiocarbamate-base resin was synthesized utilizing the reaction between carbon disulfide and immobilized amines on the fully cross-linked side of the styrene-maleicimide (SMI) copolymer. The sorption characteristics of the synthesized resin for copper, lead, nickel, zinc, and cadmium ions were investigated, using atomic adsorption spectroscopy (AAS). The sorption capacity of the resin for each metal ion was studied as a function of pH and time. The optimum pH range for sorption of the metal ions was between 4 and 6. The capacity of the resin for the metal ions decreases in the following order: Cu(II) ≈ Pb(II) > > Zn(II) > Ni(II) > Cd(II). The sorption rate of the metal ions in the resin decreases in the following order: Zn(II) > Ni(II) > Cd(II) > Pb(II) > Cu(II). The affinity of the resin for the ions was also studied using a mixture of the heavy metal ions. The capacities of the new resin, especially for copper and lead, are significantly higher than previously studied resins. Additionally, it was shown that desorption of the captured ions from the resin within 24 h can be done using 1 M nitric acid solution.
Show more [+] Less [-]Cu(II) Biosorption and Competitive Studies in Multi-ions Aqueous Systems by Arthrobacter sp. Sphe3 and Bacillus sphaericus Cells: Equillibrium and Thermodynamic Studies
2012
Aryal, Mahendra | Ziagova, Maria G. | Liakopoulou-Kyriakides, Maria
Arthrobacter sp. Sphe3 and Bacillus sphaericus cells were used for Cu(II) biosorption. The effect of contact time, biosorbent dose, equilibrium pH, temperature and the presence of other ions on the efficiency of the process were extensively studied. Optimum pH value and biomass concentration were determined at 5.0 and 1.0 g/l, whereas contact time was found to be 5 and 10 min for Arthrobacter sp. Sphe3 and Bacillus sphaericus biomass, respectively. Equilibrium data fitted very well to Freundlich model (R ²â=â0.996, nâ=â2.325, K fâ=â8.141) using Arthrobacter sp. Sphe3. In the case of B. sphaericus, a Langmuir adsorption model [R ²â=â0.996, Q ââââ=â51.54 mg-Cu(II)/g] showed to better describe the results. Potentiometric titration and Fourier transform infrared (FTIR) spectroscopy showed that amine, carboxyl and phosphate groups participate in Cu(II)-binding. The calculated thermodynamic parameters indicated the spontaneous and feasible nature of Cu(II) biosorption on both biosorbents. Selectivity of Cu(II) biosorption was examined in binary and multi-ions systems with various anions and cations which are commonly found in municipal and industrial wastewater. A specificity towards Cu(II) was observed in binary mixtures with Cl⁻, CO ₃ ⁻² , NO ₃ ⁻ , SO ₄ ⁻² , PO ₄ ⁻³ , Mg+² and Ca+², and As(V) with the maximum uptake capacity remaining constant even at high competitive ion’s concentrations of 200 mg/l. Desorption studies showed that Cu(II) could be completely desorbed from Cu(II)-loaded Arthrobacter strain Sphe3 and B. sphaericus biomass using 1.0 and 0.8 M HCl, respectively, and both bacterial species could be effectively reused up to five cycles, making their application in wastewater detoxification more attractive.
Show more [+] Less [-]Adsorption of Cu²⁺ on Amine-Functionalized Mesoporous Silica Brackets
2012
Hu, Zhihui | Zhang, Xiaodan | Zhang, Donghui | Wang, Ji-xiao
A directly amine-functionalized mesoporous silica (AMS) was prepared via an anionic surfactant-mediated synthesis method and used as adsorbents for deep removal of Cu ions from aqueous solution at room temperature. The synthesized AMS had been characterized by X-ray diffraction, nitrogen physisorption measurement, and thermogravimetric analysis. The amine groups prefer to position to the surface of AMS material due to the SN ∼ I mechanism. Copper adsorption process had been studied from both kinetic and equilibrium points of view for AMS material. Experiments proved that the aqueous Cu adsorption rates were fast and adsorption capacity was about 53.3 mg/g.
Show more [+] Less [-]Adsorptive Removal of Pentachlorophenol by Anthracophyllum discolor in a Fixed-Bed Column Reactor
2012
Rubilar, Olga | Tortella, Gonzalo R. | Cuevas, Raphael | Cea, Mara | Rodriguez-Couto, Susana | Diez, María Cristina
This study investigates pentachlorophenol (PCP) adsorption by the white-rot fungus Anthracophyllum discolor in a fixed-bed column reactor. PCP adsorption at different concentrations (20, 30, and 50 mg L−1) and pH values (5.0, 5.5, and 6.0) was determined and modeled using the Thomas model. Fourier transform infrared spectroscopy (FTIR) was used to identify functional groups of biomass that may participate in the interaction of PCP. The biosorption capacity of A. discolor was pH-dependent, and the PCP adsorbed increased with the decrease in the pH solution. Acid pH values of the influent gave an increase in saturation time in all PCP concentrations. By contrast, the increase in PCP concentration caused that the binding sites were filled quickly, resulting in a decrease in saturation time. The Thomas model was found suitable for describing the entire dynamic of the column with respect to the PCP concentration and pH of the solution. FTIR results showed that amines, carboxylates, alkanes, and C–O groups might participate in the PCP adsorption on the biomass surface. It was concluded that A. discolor biomass was a good adsorbent for PCP removal from influent with mainly acidic pH.
Show more [+] Less [-]Carbon Dioxide Capture with Amine-Grafted Activated Carbon
2012
Houshmand, Amirhossein | Daud, Wan Mohd Ashri Wan | Lee, Min-Gyu | Shafeeyan, Mohammad Saleh
There are several possible methods by which amine groups can be grafted on the surface of activated carbon (AC) to improve their capacity for CO2 adsorption. Ethylenediamine and diethylenetriamine were selected as amino compounds for anchoring on the surface of an oxidized AC. Oxidation of AC was carried out by concentrated nitric acid. For each amino compound, two “in-solvent” and “solvent-free” methods with a number of grafting times were studied. Nitrogen adsorption–desorption at 77 K and proximate and ultimate analysis were used to determine physical and chemical characteristics of the samples. Temperature-programmed (TP) CO2 adsorption test from 30°C to 120°C were performed to investigate the effect of modification on CO2 capture. The modification clearly had a negative effect on the textural characteristics of the samples, so the samples showed a less CO2 uptake at lower temperatures. However, the decrease of capture capacity with increasing temperature is to somewhat softer for amine-grafted samples, so that they have a capacity comparable to the parent sample or even more than that at elevated temperatures. This property may give the new adsorbents this opportunity to be used at flue gas temperature with a higher efficiency. CO2 capture capacity per unit surface area of all the amine-modified samples, however, was significantly improved, compared to the parent sample presenting a great influence of amino groups on the CO2 capture capacity. Moreover, the used amine compounds and grafting methods were compared in terms of adsorbent characteristics and CO2 uptake curves. Cyclic adsorption–desorption tests showed a satisfactory regeneration for the modified samples.
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